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ZHANG Dong, GE Liangsheng, LV Xinbiao, QI Ran, YAN Jiapan, ZHAO Youzhi
2025,71(3):719-732, DOI: 10.16509/j.georeview.2024.07.025
Abstract:
Knowledge and understanding of the application of geological process to warfare and peacetime practices have been fundamental to military operation, operational environment, battlefield intelligence and MOOTW. Military geology is the term used to describe this area of geological knowledge. Over time the application of military geology has changed as these military requirements such as weaponry, battlespace and geopolitical influences have altered the scale and dynamics of military operations, the concept of military geoscience is formally proposed. Military geoscience focuses on military activities of multi- material, multi- layer and multi- system environmental properties within the earth, on the basis of multifaceted disciplines of earth science. This paper summarizes the past history lessons of military geology and induced five research fields of military geoscience abroad, including of the impact of geo- environment on historical warfares, the impact of earth science on military activities, geopolitical security interests and resource needs, as well as geoscience technologies in military activities, it is suggested that the research progresses and key scientific problems on military geoscience need to be more focused on great military demands and applications such as theory and methodology, typical scenarios and global issues. Therefore, there are several research challenges to be addressed as five follows: ① the intelligent application of battlefield geospatial intelligence; ② RS recognition technology for hidden targets in unknown area; ③ military geoforensics of battlefield reconnaissance and trace identification; ④ military new energy security; ⑤ military geoscience in modern warfare. Above overview of achievements will be an important research evidence for domestic military geoscience on disciplinary development and military application.
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ZHANG Zhigang, SONG Zhihong, LIU Genyuan, CHEN Yansi, SUN Kang, CUI Xuemei
2025,71(3):733-740, DOI: 10.16509/j.georeview.2024.11.092
Abstract:
Great power competition is a major theme in today’s world. Strategic minerals are essential to a country’s economic development and are not only indispensable for military applications and national defense security, but are often profoundly influenced by geopolitics. It is of great significance to study the strategic key minerals in China and support the construction of national security by studying the application prospects of strategic minerals in the military under the background of great power competition. In view of the current frequent conflicts in the world, this paper starts from strategic minerals, combs the representative strategic mineral military application fields of energy, metal and non- metallic minerals respectively, puts forward suggestions for strategic mineral renewal and supply chain security according to the current situation of China, discusses the application prospects of strategic minerals in the future, provides a certain reference value for the military application of strategic minerals in China, and provides effective support for the realization of China’s medium and long- term mineral resources security.
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ZHAN Chun, YANG Hu, LIANG Jun, ZHANG Tao, WANG Jia, HE Tao, LI Chenyu, LIU Cheng
2025,71(3):741-753, DOI: 10.16509/j.georeview.2024.11.051
Abstract:
To conduct an in- depth study on the constraints and influence mechanisms of different geological factors on military activities such as engineering construction, equipment utilization, firepower strikes, and logistical support for mobility, this paper preliminarily explores the military winning mechanism of soil within geological elements. The aim is to provide a theoretical basis grounded in geology for utilizing and transforming battlefield environments to enhance combat effectiveness.Results: In this study, the authors utilize a comprehensive training ground as a "testing field," focusing on military training activities within specific functional areas. The research centers around five typical types of soil found in the training ground. Field tests were conducted to gather data from these locations, along with sample collection for analysis aimed at obtaining physical and mechanical parameters of the soils. Furthermore, we investigate the coupling relationships between significant physical properties and mechanical parameters.Conclusions: The results indicate that moisture content, void ratio, and longitudinal wave velocity are critical mechanistic factors influencing soil behavior. These factors significantly affect resistance to explosive impacts, mobility during operations, and fortification construction in military contexts. Consequently, understanding the relationships among soil moisture content, porosity ratios, and compressive modulus can guide various military activities- including fortification deployment during exercises- and also has substantial implications for strategic decision- making related to operational actions such as strikes and logistical support.
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WANG Zhongyu, TONG Zhiqiang, WANG Zhen, GU Majun, LIU Qimin
2025,71(3):754-762, DOI: 10.16509/j.georeview.2024.12.121
Abstract:
How to improve off- road mobility in the future battlefield environment is crucial to the success or failure of a campaign. The off- road is not only determined by the power unit and body performance of the vehicle itself, but also by the passability of various complex terrains. The bearing capacity of elements directly affects the passability of the road surface. In order to adapt to the future informationized battlefield with large depth, wide area, and high speed requirements this study simulated the mountain and forest battlefield environment, and carried out a special geological survey task in a certain area in Northeast China. The authors relied on this project conduct soil survey tasks, using simple bearing capacity measuring instruments to obtain the types of surface soil, physical properties of soil, and distribution characteristics of different areas, and with geological drilling, high- density electrical measurement and other technical means to obtain the soil layer structure characteristics and soil mechanics characteristics of the main traffic roads such as S202 and S319 in the study area, and made qualitative analysis and evaluation on the bearing capacity of the main soil types such as gravel soil, sandy, cohesive soil, and special soil. Based on the survey data, the main factors affecting the bearing capacity of the soil were analyzed, and the off- road mobility different road surfaces in the mountain and forest landscape was studied.
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LU Junjie, CHUN Lan, KONG Fanquan, LIU Shiqiao, WANG Jinli
2025,71(3):763-768, DOI: 10.16509/j.georeview.2024.11.022
Abstract:
This paper explores the application prospects of zirconium—hafnium materials in the military field. Zirconium and hafnium exhibit significant potential in aerospace, nuclear industries, and armor protection materials due to their high melting points, excellent corrosion resistance, and thermal conductivity. In particular, zirconium diboride (ZrB2) and hafnium diboride (HfB2) materials are widely utilized in the thermal protection systems of hypersonic vehicles and re- entry spacecraft due to their stability in extreme high- temperature environments. Zirconium alloys are ideal structural materials in nuclear reactors because of their low neutron absorption cross- section and corrosion resistance. This paper also discusses the challenges in the manufacturing processes of these materials and future development directions, highlighting their potential and significance in emerging military technologies.
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YANG Hu, ZHANG Mingyuan, ZHAN Chun, WANG Jia, LIANG Jun, LI Chenyu
2025,71(3):769-783, DOI: 10.16509/j.georeview.2024.11.061
Abstract:
The high and cold region of Tibet Plateau has special geological environment, and as an important war preparation area, it is of great strategic significance to carry out research on the correlation of battlefield environment guarantee in the region. This work selects a training site, makes full use of elastic wave theory, explosion theory and technical methods in the firearm drop area, and selects the target area to carry out seismic wave acquisition and processing, numerical simulation calculation of rock and soil media explosion, etc., studies the destructive effects of artillery shells (explosives) on rock and soil surfaces in the field (shooting range), and evaluates its anti- explosion performance. The research shows that, Rock medium is much less destructive than soil medium. However, under different lithology conditions, the anti- blast ability of tuff, rhyolite and andesite after penetration explosion is less than 5 cm. This shows that the rock medium has much higher anti- knock capability than the soil medium, and the difference of the rock medium's anti- knock capability is small in this area. In this study, the application of simulation in the study of anti- explosion strike performance on the battlefield is discussed and verified by practice. At the same time, it also provides a reference for further developing the application of computer simulation in battlefield environment protection.
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WANG Liang, GE Liangsheng, QI Ran, ZHANG Dong, YANG Shuqi, JIA Liqiong
2025,71(3):784-798, DOI: 10.16509/j.georeview.2024.11.042
Abstract:
Weaponry equipment constitutes a vital foundation for military preparedness, and their environmental adaptability is of paramount importance.The geological environment, as a significant component of the natural environment for weaponry equipment, exerts notable influences on the performance, reliability, and service life of weapon systems, yet it has been overlooked in previous environmental adaptability studies. Based on the elucidation of the conceptual connotations of weaponry equipment environment and geological environment, this paper proposes the characteristics and trends of equipment environment that under joint warfare conditions. It explores the role and practical application of the geological environment in the development, navigation and guidance, mobility, firepower application, water supply, and maintenance of military equipment. Finally, by reviewing advancements in natural environment testing, environmental worthiness assessments, and environmental weapon development abroad, this paper presents three insights for the research and engineering practice of geological environment worthiness for weaponry equipment in China, aiming to facilitate the development of high environmental worthiness throughout the entire lifespan of equipment across all domains and contribute to the high- quality development of weaponry equipment.
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ZHANG Bin, YANG Kun, YANG Runbai, ZOU Shilin
2025,71(3):799-813, DOI: 10.16509/j.georeview.2024.11.032
Abstract:
The Battle of Songshan in western Yunnan was an important battle in the Chinese People’s War of Resistance against Japanese Aggression, and its victory was a significant turning point in Chinese strategic counteroffensive, which played a key role in strengthening the determination and confidence of the military and civilians in the resistance war. From the perspective of war geology, this paper studies the application of geological elements of the Battle of Songshan historical battlefield and their influence on tactical deployment and strategic decision-making. By analyzing the characteristics of the battlefield geological environment in the main battle areas, this paper discusses the impact of the geological conditions of the Songshan Battlefield on the selection of battlefield, fortification construction, tactical movements, and strategic planning. The case studies show that geological factors played a key role in the battle, not only affecting battlefield selection and fortification construction, but also having a profound impact on tactical movements and strategic planning, which provided an empirical basis for the military geological research of the battle of Songshan, and offered new research ideas for the application of geology in modern warfare.
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ZHANG Dong, GE Liangsheng, WANG Weibing, LI Hongwei, WEI Haiping, LI Yongsheng, ZHAO Youzhi, KONG Di
2025,71(3):814-826, DOI: 10.16509/j.georeview.2025.02.015
Abstract:
Military geological data is an important metadata in the field of geoscience to study the ground characteristics of typical military activity scenarios, which is helpful to understand the dynamic change process of geographic space and provides a new perspective for the customized military geo- services. Military geological data reflects the information of underground geological structure, and standardized data processing and effective military methods are becoming an important challenge for the military application of multi- source heterogeneous geoscience data. Based on the big data characteristics of military geological data, this paper attempts to construct a standardized processing solution for military geological elements, military conversion from civilian geological data, military geological database and data analysis model indexes, and to discuss the application of military geological standard data. The research progress includes as follows: (1) There are not only big data characteristics of multi- source heterogeneity, multi- modality, high integration and complexity, but also unique data characteristics of diversified time—space—physical—chemical property, and applications characteristics of rapid- steric- instant obtaining, static—dynamic—combat support, and target reconnaissance, including of supporting terrain structure and underground space, such as the complex geological processes and internal mechanisms in military geological data. (2) The application classification of military geological elements recommends the basic metadata types of military geological data for military applications, the military conversion from civilian geological data provides the principle of first compilation, then conversion and update, the military geological database fulfills the big data analysis and utilization of data aggregation, database mapping, data management and application services, and the data analysis model indexes construct a series of quantitative impact factors with weak correlation quantitative values of a group of military geological elements in the mountainous landscape. (3) Military geological element data and its vector layer overlap analysis with geographic information data satisfies the military needs of geospatial intelligence. Standardized military geological data using GIS tools can implement the customization of military geo- services with data quantitative processing, spatial analysis and mapping, so as to support the relevant theme layers, operational scenarios and instant information by geo- support in time- critical missions. Applications with modern big data technology of intelligent extraction and integrated expression, military geological standard data should have a unified element classification, a unified spatial datum, a database preparation and a customized symbol system of thematic map data for geo- services. The research results can be used to standardize the connection between military geological data and military digital information fruits, and to provide a useful tool for battlefield environmental support of precision, informationized and intelligent analysis.
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ZHANG Zhijun, DONG Yusen, HE Kang, WANG Yanliang, HUO Runbin, KONG Di, WANG Lizhe
2025,71(3):827-837, DOI: 10.16509/j.georeview.2024.11.041
Abstract:
The selection of temporary helicopter landing sites in complex geological environments, such as high- altitude, plateau, and mountainous regions, is crucial for military operations and emergency rescue missions.In the past, geographical factors were mainly considered in the study of heliport site selection, but the distribution of rock and soil mass, structure and geological disasters in the complex geological environment also hinder the helicopter site selection.Low assessment efficiency and accuracy are also the main problems.Methods: This paper addresses the challenges of low assessment efficiency and accuracy in selecting helicopter landing sites within such environments by proposing a weighted information- based model for site evaluation, utilizing remote sensing and auxiliary data. The model comprehensively considers geographic and geological factors relevant to site selection, ensuring rational and efficient site identification. Eight types of geographic and geological remote sensing datasets were used to design site selection criteria, which were quantified using the weighted information method. These criteria were then classified adaptively using the Jenks natural breaks method to generate a multi- category helicopter landing site suitability map, typically distinguishing areas such as suitable and hazardous zones. Results:An AlphaShape- based convex hull search was developed to perform adaptive filtering of salt- and- pepper noise, further optimizing the site selection outcomes.Experiments demonstrate that the newly introduced geographic and geological environmental factors, including geological hazards, land cover, rock—soil type, RCI index, and joint structure, are critical indicators influencing site selection that were previously overlooked. Conclusions:The proposed model significantly enhances the rationality, safety, and automation of helicopter landing site selection, while the filtering algorithm effectively reduces noise, improving the reliability and practicality of the results.
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HE Kang, DONG Yusen, WANG Lizhe, ZENG Fei, QIAN Yihan, LI Huili
2025,71(3):838-847, DOI: 10.16509/j.georeview.2024.11.015
Abstract:
The evaluation of landing sites is a critical component of maritime rescue, disaster emergency response, and material delivery operations, influenced by various factors such as coastline topography, seabed composition, and geographical and geological environments. Existing evaluation methods typically rely on a limited set of influencing factors (e.g., coastline topography, seabed composition, vegetation cover) and qualitative manual rule- based approaches, which suffer from few- factor, experience- based limitations, failing to meet the needs for quick, safe, flexible, and cost- effective landings. To address these issues, this paper proposes an evaluation model based on the entropy- weighted Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS), which comprehensively considers hydrological, coastal geographical, and geological attributes. First, an evaluation index system is established, encompassing four primary categories of indicators—maritime factors, transportation factors, geographical factors, and geological elements—along with their detailed sub- indicators. Then, weights are assigned to each factor using the entropy weighting method, and the TOPSIS model is used to calculate the relative closeness of each landing site to assess landing suitability. Finally, the evaluation results are filtered based on the landing width requirements of standard landing craft, producing the final landing evaluation map. A typical coastline is selected as a case study for analysis, and the results show that transportation and geological factors are critical indicators affecting landing site evaluations, which were often overlooked in previous studies. The entropy- weighted TOPSIS model identifies six safe, flexible, and economical landing points along the chosen coastline.
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ZHAO Junli, LI Xiangying, CHEN Zhanlong, ZENG Fei, HAN Sipeng, ZHANG Feng, SUN Chenxing
2025,71(3):848-866, DOI: 10.16509/j.georeview.2024.11.002
Abstract:
Military geology has become an essential component of the three- dimensional, transparent, and information- driven battlefield environment. Remote sensing technology provides extensive, dynamic, multi- perspective, and repetitive data for ground observation, offering rich data sources for the extraction and application of military geological information. This article presents an overview of military geology and related remote sensing image data, focus on current research in the extraction and application of military geological information from remote sensing images, including rock formations, soil bodies, water bodies, geological structures, geological hazards, and geological resources. It summarizes and analyzes the challenges and development trends in military geological information extraction and application, highlighting issues such as low accuracy and instability in the extraction process, which limit the potential of military geological elements in military applications. In the future, with the rapid advancement of technologies such as deep learning, artificial intelligence, and large language models, the extraction and application of military geological information based on remote sensing images hold promising prospects.
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ZHANG Wenhua, LI Na, YAN Jialiang, XU Jiaqi, WANG Jiabao
2025,71(3):867-874, DOI: 10.16509/j.georeview.2024.12.115
Abstract:
With the continuous evolution of modern battlefield models, military geological factors, as one of the five major elements of the battlefield environment, have increasingly garnered attention for their importance. Military geological data is a specific carrier of these factors. More and more collection methods have led to surge in geological data related to the battlefield environment. In order to solve the bottlenecks such as data integration of multi - source, formats, scales, and database types, this article is based on MapGIS10 to study military geological data conversion, data source unification, data consistency maintenance, and data sharing among different application systems in heterogeneous environments.This research holds significant practical value for providing service support related to military geological factors
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LIU Yuxin, MA Wen, LI Hongwei, CHEN Yongling, ZHANG Tao, MENG Cheng
2025,71(3):875-884, DOI: 10.16509/j.georeview.2024.11.031
Abstract:
Military geology is mainly oriented to the exploration and research of complex geological environment in typical scenes. Modern high-tech warfare puts forward higher requirements for military geological informatization and refinement. The application of modern engineering geological analysis methods to military geological application research is increasingly important for the development of military geological technology.Methods:On the basis of summarizing the traditional research methods of engineering geology, this paper discusses the typical cases of engineering geological analysis methods in military geological application research.Results:The research shows that the natural history analysis method, as an effective method for military geological application research, can play an active role in military applications such as military transformation of civil geological data, assessment of mobile traffic capacity, assessment of fortification stability and resistance to strike, and risk assessment of key geological disasters.Conclusions:The application characteristics of multidisciplinary cooperation in modern military geology determine a new way for the integration and development of modern engineering geological analysis methods and other geoscience research ideas and methods, which may become an important ability to promote military geology to solve practical military problems.
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LI Yunfeng, LIU Zhijie, CHEN Yang, LI Taotao, WANG Cen, LI Chaoteng
2025,71(3):885-894, DOI: 10.16509/j.georeview.2024.11.045
Abstract:
Accurately obtaining attribute information of military geological elements can effectively support the construction of the battlefield geological environment guarantee system and provide basic data support for military decision- making. Traditional methods for obtaining military geological elements, such as field surveys or manual interpretation of remote sensing images, are characterized by high costs, low efficiency, and uncertain accuracy when obtaining data from unfamiliar areas. Utilizing known regional data and machine learning and deep learning methods to construct a military geological element attribute model for hyperspectral satellite imagery has become an effective means of obtaining data from unfamiliar regions. This paper proposes a machine learning- supported method for predicting the basic quality level of rocks, which performs well in predicting the basic quality level of rocks in unfamiliar areas. Based on collecting basic quality grade data of rocks in the research area, a sample dataset was created using the Resource One 02E hyperspectral satellite data as the data source. SVC, RF, XGBoost, Stacking, Blending, and ResNet50 machine learning methods were employed, applied to study the prediction model of the basic quality grade of rocks in unfamiliar areas. The research results show that the ResNet50 model is the best prediction model for the basic quality grade of rocks in the study area, with a prediction accuracy of 65.53%. The Stacking model follows with a prediction accuracy of 41.53%, and the blending model has the lowest prediction accuracy. The overall prediction results of the model reflect a clear spatial differentiation of the basic quality grades of rocks in the study area, presenting a spatial distribution characteristic of higher basic quality grades of rocks in the north, mainly grades I and II, and lower basic quality grades of rocks in the southwest, mainly grades IV and V. The basic quality grade of rocks in unfamiliar areas is mainly grade III or below, with higher basic quality grades in the northeast direction. The research aims to provide a basis for the acquisition and application of military geological data.
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LIU Xiaoyu, YANG Wencai, QU Chen
2025,71(3):895-902, DOI: 10.16509/j.georeview.2024.12.001
Abstract:
After the collision between the Indian Subcontinent and the Asian Continent, the Indian Subcontinent is subducting below the Asian Continent. The continental collision and land- to- land subduction not only caused the crust of the Qinghai—Xizang(Tibet) Plateau being shortened and thickened, but also led to significant changes in the geomorphological environment and deep structures of the vast area around the plateau. Is there a large amount of material wriggling from below the plateau to South China Craton and/or North China Craton? Does it cause the uplift of the Yunnan—Guizhou Plateau? In this paper, high- resolution seismic tomography is used to study the creep of materials from below the plateau and the uplift of the Yunnan—Guizhou Plateau. Seismic tomography shows that during the collision and subduction between the Indian Subcontinent and the Eurasian Continent, the lithospheric material of the Qinghai—Xizang Plateau was extruded under the upper Yangtze Craton, and the extrusion occurred in the middle of the lithospheric mantle at a depth of 73~113 km, along the route of Yidun—Xichang—Dongchuan—Anshun. One of the consequences of the extrusion of material from the central lithospheric mantle of the Qinghai—Xizang Plateau is the increase of the lithospheric volume, and causing uplift of the Yunnan—Guizhou Plateau.
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LV Boye, WAN Sheng, LIU Junping, HE Shijun, MA Chenglong
2025,71(3):903-920, DOI: 10.16509/j.georeview.2025.01.042
Abstract:
The widely exposed Neoproterozoic Chengjiang Formation on the western margin of the Yangtze Block represents a sedimentary rock series closely related to the evolution of the Rodinia supercontinent. Its formation time limit and tectonic background have significant implications for the Neoproterozoic basin evolution in South China and the reconstruction of ancient continents.Results: Through field investigations, two layers of volcanic interbeds were discovered at the top of the Chengjiang Formation in the Luquan area of Yunnan Province. The lithology is gray- white rhyolitic crystal tuff. LA- ICP- MS zircon U- Pb dating of the tuff yielded a weighted average age of 735. 6±5. 2 Ma (n=24, MSWD=0. 14), it indicates that the eruption age of tuff is in the early Nanhuan Period.Thus constraining the depositional time limit of the Chengjiang Formation to 812~735. 6 Ma. Rock geochemical and Lu—Hf isotopic studies reveal that the crystal tuff is significantly enriched in large ion lithophile elements (LILE) such as Rb, Th, and K, and depleted in high field strength elements (HFSE) such as Ba, Sr, P, Ti, Nb, and Ta. The rare earth element distribution curve exhibits a "swallowtail" pattern, consistent with the characteristics of the low- Sr, high- Yb Nanling- type granite. Its formation originated from 5%~10% partial melting of Mesoproterozoic early (TDM2: 1932~1265 Ma, with an average value of 1704. 3 Ma) lower crustal argillaceous rocks, with minor mantle material involvement. Conclusions: It formed in an extensional tectonic setting, related to the breakup of the Rodinia supercontinent in the South China block, and represents significant petrological and magmatic records of the Nanhua rift.
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MO Tao, PAN Yongshuai, FAN Kunyu, LIU Bo, ZHU Wenhui, HUANG Zhilong, WANG Yuan
2025,71(3):921-940, DOI: 10.16509/j.georeview.2024.10.011
Abstract:
A large set of thick sand bodies is developed in the Second Member of the Cretaceous Bashijiqike Formation (the Ba- 2 Mem.) (K1bs2) in the Bozi—Dabei area of Kelasu structural belt, but there are few detailed studies on the difference of lithofacies and reservoir formation mechanism under the control of sedimentary microfacies, which seriously limits the success rate of exploration. Therefore, this paper systematically carried out the study of favorable lithofacies characteristics and high- quality reservoirs formation mechanism of the Ba- 2 Mem., which is conducive to improving the success rate of natural gas exploration and development.Methods:In order to clarify the favorable lithofacies characteristics and reservoir formation mechanism of the deep sandy braided river facies containing muddy gravel in the Ba- 2 Mem., the lithofacies types, distribution rules, reservoir characteristics and formation mechanism of high- quality reservoirs in the study area are analyzed in combination with core observation, laser particle size analysis, whole rock and clay X- ray diffraction, casting thin sections, scanning electron microscopy, routine rock analysis (porosity and permeability), high pressure mercury injection, nuclear magnetic resonance and logging data. Results: ① The sedimentary system of the underwater distributary channel in the front of the sandy braided river delta with muddy gravel is widely developed in the study area, and the reservoir is dominated by feldspathic lithic sandstone. Vertically, the Ba- 2 Mem. can be divided into 5 sand groups, and the single sand group develops successively from bottom to top of the muddy gravel- rich massive medium—fine sandstone lithofacies, muddy gravel—medium massive medium—fine sandstone lithofacies, massive medium—fine sandstone lithofacies, stratified silt—fine sandstone lithofacies and massive mudstone lithofacies. ② The Ba- 2 Mem. sand body is characterized by low porosity and low permeability reservoir, and the lithofacies types developed in the microfacies of the underwater interdistributary bay are poor in physical properties, pore structure and fluid mobility, while the ones controlled by the microfacies of the underwater distributary channel are better. The reservoir mainly develops primary intergranular pores and intergranular dissolution pores, with local micro- fractures and intragranular dissolution pores. ③ The large set of medium—fine sandstone formed in the microfacies of the underwater distributional channels is the basis for the formation of the Ba- 2 Mem. high- quality reservoirs, and the diagenetic transformation of different structural locations and different types of reservoirs is different. Among them, late rapid burial compaction is the main factor of reservoir densification, followed by large cementation in early and middle period. The key factors for the formation of high- quality reservoirs are the retention of pores in the overlying thick layer of gypsum—salt rock, the early atmospheric freshwater dissolution, the late organic acid dissolution and the micro- fractures associated with intense tectonic movement. Conclusions: Based on a variety of macro and micro analysis and test data, this study systematically analyzed sedimentary microfacies types, lithofacies characteristics, pore structure differences among different lithofacies, and the effects of sedimentation, diagenesis and tectonic processes on the formation of high- quality reservoirs of the Ba- 2 Mem. (K1bs2), which has certain guiding significance for deep—ultradeep oil and gas exploration.
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YAN Han, LI Xiyao, YAO Yuxiao, LI Sanzhong, DAI Liming, WANG Yu
2025,71(3):941-958, DOI: 10.16509/j.georeview.2024.10.095
Abstract:
Calderas, as the most distinctive landform of volcanoes, are volcanic depressions formed by surface collapse due to the eruption of magma. They are closely related to processes such as magma migration, eruption, and chamber depressurization. The dynamics of caldera collapse has always been a hot topic in volcanology and volcanic disaster. This paper reviews the main types, evolutionary processes, collapse conditions, and influencing factors of calderas. It also analyzes the research progress in volcanic geological characteristics, mathematical models, physical models, and numerical simulations of caldera collapse. The studies can provide new insights into magma migration and eruption during caldera collapse. Furthermore, the combination of volcanic geology and geophysical research on caldera collapse can offer a new perspective for volcanic monitoring and disaster mitigation, while also yielding valuable insights for future studies of caldera.
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XIAO Kunze, TONG Hengmao, CUI Hao, XU Xiaoke
2025,71(3):959-978, DOI: 10.16509/j.georeview.2024.12.042
Abstract:
As one of the most famous faults in China, the Tan- Lu Fault Zone in eastern China has attracted much attention from researchers at home and abroad since it was discovered. A series of Cenozoic hydrocarbon basins associated with this fault zone are developed along it, which makes its Cenozoic structural characteristics a research hotspot in academia and the petroleum industry. However, the current understanding is still many controversies. Based on a systematic review of the main research advances in the Tan- Lu Fault Zone, the article focuses on the deformation characteristics of faults, the evolution history and its mechanism, the initial period of dextral slip and the amount of strike- slip displacement since the Cenozoic. Furthermore, the article also discusses the controversy of the research advances based on the generalised fault theory. It proposes that the dextral slip in the Tan- Lu Fault Zone since 38 Ma is a new insight owing to the differential re- activation of a large- scale pre- existing structure (the Tan- Lu Fault Zone) under the nearly north—south extensional tectonic setting. The article uses analogue modelling to investigate this insight. The article hypothesises that the dynamics of the almost north—south extensional tectonic setting may derive from the slab- window effect produced by the subduction of the near east—west spreading mid- ocean ridge between the Pacific — Kula Plate. The above new insights can provide a reasonable explanation for the deformation characteristics of the dextral slip, the differential distribution of strike- slip displacements in the Tan- Lu Fault Zone, and the complex structural and sedimentary features in the adjacent basins along its strike. In addition, the new insights into the mechanism of dextral slip of the Tan- Lu Fault Zone in the Cenozoic, may provide useful inspiration and guidance for future structural investigations in eastern China, as well as for the exploration and development of oil and gas basins along the fault zone, and the development and utilisation of mineral resources.
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WANG Yinuo, JIANG Dayong, JI Cheng, SUN Zuoyu, ZHOU Min
2025,71(3):979-996, DOI: 10.16509/j.georeview.2024.10.052
Abstract:
The Upper Member of the Middle Triassic Guanling Formation in Luxi, Yunnan yields abundant fossils, including marine reptiles, fishes, arthropods, echinoderms, mollusks, brachiopods and plants and the fossil assemblage in Luxi is similar to that of the Panxian Fauna and Luoping Biota. However, the biostratigraphy study in Luxi is poor, making it difficult to accurately determine its geological age. In this study, LA- ICP- MS U- Pb analysis was performed on volcanic tuff samples from the major fossil sites, including Suomeiluo and Muta sections in Luxi and Gejiehe section in Panxian, Guizhou. Methods: Four volcanic tuff samples were collected from the Suomeiluo and Muta sections in Luxi, Yunnan. One volcanic tuff sample was collected from the Gejiehe section in Panxian, Guizhou. The LA- ICP- MS analysis was carried out in Mineral Laser Microprobe Analysis Laboratory (Milma), China University of Geosciences (Beijing). Before isotopic analyses, the internal structure of the zircons was examined using cathodoluminescence (CL). 30 zircons with clear oscillatory zoning were selected for the analyses in each sample. Uncertainties for each analysis were reported at the 2σ level. Data reduction and U- Pb concordia diagram were carried by Isoplot.Results: The results show that the age of the volcanic tuff sample of the Suomeiluo Section is 243. 9±1. 8 Ma, and ages of three samples of Muta Section from the bottom to top are 245. 2±3. 4 Ma, 243. 7±1. 7 Ma and 242. 2±1. 5 Ma, respectively. The zircon age of the volcanic tuff sample from the Gejiehe Section is 244. 0±1. 5 Ma. Conclusions:According to the dating results, the fossiliferous layers of the Upper Member of Guanling Formation in Luxi are in Pelsonian substage of the Anisian (Middle Triassic), which is chronologically consistent with the Panxian Fauna and Luoping Biota.
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ZHAO Weice, CHEN Jiade, WEI Liangmin, LI Wei, QIN Jijun, LIU Aixin, LIU Zi
2025,71(3):997-1010, DOI: 10.16509/j.georeview.2024.10.075
Abstract:
The Haobugao polymetallic district in Inner Mongolia is located within the Huanggangliang—Ganzhuermiao metallogenic belt of the southern Great Hinggan Mountains. Skarn Zn—polymetallic, porphyry Mo, and granite- hosted Sn mineralization occurred during the Mesozoic magmatic intrusion. However, the relationship of the granite- hosted Sn mineralization with skarn Zn—polymetallic and porphyry Mo mineralization remain obscure, and are poorly understood.Methods: In this paper, based on detailed field geological work, granite- hosted Sn ores in the Wulanba pluton are investigated as an ideal objective. Two cassiterite samples were collected to date the U- Pb ages via LA- MC- ICP- MS method.Results: They yielded U- Pb Tera- Wasserburg lower intercept ages of 148. 7±5. 1 Ma and 146. 4±3. 4 Ma, respectively. The data suggests that granite- hosted Sn mineralization at Haobugao is coeval with the emplacement of the alkaline granite in the middle part of the Wulanba pluton (148. 9~142. 0 Ma), and thus indicating a consistency in space and time.Conclusions: Combined with previous studies, we propose that granite- hosted Sn mineralization can be spatially, temporally and genetically related with skarn Zn—polymetallic and porphyry Mo mineralization at Haobugao, and formed by the Late Jurassic—Early Cretaceous magmatism and related mineralization. In addition, the timing of Sn mineralization at Haobugao (148. 7~139. 6 Ma) coincides with that of large- scale Sn—polymetallic metallogeny in the southern Great Hinggan Mountains (150~130 Ma). We thus propose that, in combination with regional tectonic evolution, the Haobugao Sn—polymetallic district formed in an extensional tectonic setting.
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DING Yi, XIAO Bingjian, HOU Zheng, WANG Tianyi, WANG Yufeng, DU Xianfu, ZONG Chuanpan
2025,71(3):1011-1019, DOI: 10.16509/j.georeview.2024.10.085
Abstract:
Besides their economics, geoscientists can study geology in deep mantle through diamondiferous kimberlites or diamondiferous Lamproites, and there have been many advances in this area worldwide. Surface element cycling and geological events in the mantle were discovered through inclusions and fluids contained in diamonds. The C—P—T—PH2O conditions for determining the origin of mantle magma were determined through DKL mantle xenoliths and xenolith crystals. The scientific research value and economic value of DKL have also driven the discovery of multiple DKL fields in Angola, Russia, India, central Canada, and other regions, thereby promoting deep geological research. This article provides a brief overview of global research achievements in this area.
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ZHANG Minglin, LI Shengxiang, LIU Yue, GUO Qingyin, QIN Mingkuan, CHE Yongfe
2025,71(3):1020-1028, DOI: 10.16509/j.georeview.2024.10.015
Abstract:
This paper analyzes the changes of global uranium exploration expenditures, uranium resources policy and regional distribution pattern since the 2008 financial crisis, and summarizes the main progress of global uranium exploration in this period. It is estimated that the exploration investment of global uranium resources will gradually increase in the next decade. It is considered that the first target deposit type of uranium exploration is sandstone type and unconformity- related type, followed by calcrete type, intrusive rock type, breccia complex type and quartz—pebble conglomerate type. Canada, Australia, Kazakhstan, Namibia, Niger, South Africa, China, Russia, the United States, Mongolia, India will continue to be the key regions of global uranium exploration; South America may become a hot spot for uranium exploration. It is difficult to revive uranium exploration and exploitation in Europe (except Russia). New breakthroughs may be made in the prospecting for in- situ leaching sandstone type uranium deposits in Canada and southern Africa.
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WANG Jing, ZHANG Dayu, ZHANG Fei, WENG Wangfei, XU Hongbing, MENG Xiang, YANG Huawei, ZHOU Taofa
2025,71(3):1029-1045, DOI: 10.16509/j.georeview.2024.10.055
Abstract:
The Changlingjian deposit is a newly discovered tungsten polymetallic deposit, which located in the eastern sector of the Jiangnan tungsten belt (JTB). The Re- Os dating of molybdenite in the Changlingjian deposit yielded a weighted average age of 133. 8±1. 3 Ma, indicating the mineralization is genetically related with the coeval muscovite granite beneath the deposit. After detailed geological and petrographic characteristics, we subdivided the mineralization process from W—sulfide—quartz (stage I), sulfide—quartz (stage II) to calcite—quartz (stage III). The temperature and salinity calculation results of the three- stage fluid inclusions show that, there are decreasing temperature and salinity degrees from stage I (281~386℃, 0. 70%~10. 11% NaCleq), stage II (186~317℃, 0. 70%~4. 03% NaCleq) to stage III (156~202℃, 0. 70%~2. 07% NaCleq). The δ34S values of sulfides from stages I and II range from -4. 5‰ to 2. 8‰. Mineralized coexisting quartz fluid inclusions (Stage I and Stage II) δ D ranges from -70. 3‰ to -58. 3‰, and the δO H2O value obtained from the conversion of O quartz in quartz ranges from -0. 1‰ to 4. 8‰. Those stable isotopic characteristics infer that the ore- forming fluid was dominantly from magmatic fluid with some meteoric water added, and increasing meteoric water ratios along the fluid evolution. The precipitation of tungsten in the Changlingjian deposit is mainly controlled by fluid immiscibility, while the precipitation of sulfide minerals is mainly controlled by fluid mixing. Combined with reginal research, the ore- forming fluid in Changlingjian deposit has similar character with most tungsten deposits in JTB, which were consistently source from ore- forming granitoid intrusions, with mixing a small amount of meteoric water.
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LAI Jin, DANG Wenle, SU Yang, WU Yongping, ZHAO Yidi, ZHANG Youpeng, XIN Yi, BAI Tianyu, WANG Guiwen
2025,71(3):1046-1072, DOI: 10.16509/j.georeview.2024.09.091
Abstract:
In order to systematically sort out the process of acoustic logging interpretation and evaluation and expand its application field and scope, this paper reviews the development history of acoustic logging instrument acquisition series, and summarizes the differences of acoustic properties detected by different instruments. Acoustic logging can be used for calculating porosity logging calculation, evaluating permeability and identifying the layers with abundant hydrocarbon. Acoustic logging can also be used to evaluate the brittleness index of unconventional reservoir by calculating dynamic Poisson’s ratio, Young’s modulus and other parameters. According to the acoustic logging’s abnormal response to the normal compaction trend line, acoustic logging can distinguish the mechanisms of abnormal formation pressure and calculate the formation pressure quantitatively. Acoustic logging can be combined with seismic data to synthesize seismic records, and the interval transit time can be used to restore the thickness of formation denudation. The fast and slow shear wave azimuths of acoustic logging can be used to distinguish the current stress direction. The formation anisotropy coefficients can be calculated quantitatively according to the fast and slow shear wave velocity. The presence of the fracture shows the increase of interval transit time, the attenuation of acoustic energy, the appearance of “V” interference fringe in the variable density and the increase of Stoneley wave reflection coefficient in acoustic logging. The source rock has a high interval transit time, and the TOC content can be calculated quantitatively by combining with resistivity logging. Acoustic logging supports safe drilling design by calculating formation pressure, rupture pressure and collapse pressure. It can also be used to evaluate fracturing performance and the check of cementing quality based on the relative strength of the casing wave and the formation wave. The research has certain guiding significance for expanding the application field of acoustic logging.
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2025,71(3):1073-1080, DOI: 10.16509/j.georeview.2024.09.015
Abstract:
Shale oil of Qingshankou Formation of Upper Cretaceous in Gulong Sag, Songliao Basin. Methods: Based on electron backscattering and secondary imaging, combined with energy spectrum analysis and thin section observation, it is found that a kind of micron pore and micron fissures formed by hydrocarbon generation and expulsion expansion in Qingshankou Formation shale in Gulong Sag. Results: The characteristics of hydrocarbon generation and expulsion high-pressure expansion micron pores are: ① generally only developed in ultra-high pressure shale oil reservoirs; ② Generally only developed in clay feldspar shale, pure clay rock is rare; ③ Most of them are nearly circular or semi-circular, with diameters ranging from 0. 5 microns to several microns, generally 1~2 microns, but up to 8 microns; ④ The wall of the hole is generally clay, and the clay on the upper edge is curved or eyebrow shaped, and the chlorite is obvious, so it is bright and eye-catching in the backscatter image; ⑤ There are many self-generated nanoscale grape-like or soybean residue clay in the hole. ⑥ high-pressure expansion micron holes for hydrocarbon generation and expulsion can be combined into four types: vertically connected to form vertical hydrocarbon expulsion chimneys; Vertically connected to form a inclined hydrocarbon exhaust chimney; The hydrocarbon exhaust pipes connected horizontally to the bedding form larger lamellar pores in the profile. Straight or slightly curved hydrocarbon exhaust chimney; 1~3 microns wide, up to 200 microns wide; High ten to twenty or thirty microns, up to 1500 microns; The top is mostly connected with the micron slit along the bedding, which is the final pressure relief and oil and gas drainage reservoir of the hydrocarbon exhaust chimney. The porosity of hydrocarbon-generating and expelling micron pores varies greatly, generally in the range of 5%~6%. The characteristics of high-pressure expansion micron fractures for hydrocarbon generation and expulsion are: ① generally only developed in ultra-high pressure shale oil reservoirs; ② Generally only developed in clay feldspar shale, pure clay rock is rare; ③ Mainly micron cracks based on foliation; ④ slightly curved tensile cracks, mostly zigzag, bypassing minerals; ⑤ Width 1-tens of microns, up to 150 micron; ⑥ Associated with pyrite, dolomite, apatite and other authigenic minerals; ⑦ It is mostly connected with hydrocarbon generation and expulsion micron pores and expulsion chimneys. In this paper, the pressure to form the hydrocarbon-generating and expandable micropores and microcracks is calculated, and the hydrocarbon-generating and expandable micropores are formed from 44.74 MPa at 1500 m to 74.81 MPa at 2500 m depth. At the same depth, the pressure of hydrocarbon expulsion is 3 MPa larger than that of hydrocarbon expulsion micropore formation. Conclusions: This is a new genetic type of micron pore and micron fracture, is a kind of effective micron pores andmicron fractures, is the most important one in Gulong shale oil reservoir. There are two main driving forces for the formation of hydrocarbon generation and expulsion expansion micron pores: one is the high-pressure expansion tension of hydrocarbon fluids; The second is the chemical dissolution power of hydrocarbon fluids. The pressure to form the micron pore and micron slit of hydrocarbon generation and expulsion is calculated. The expansion of micron pores with hydrocarbon generation and expulsion is connected with other pores to form a storage and transportation network, which greatly increases the storage capacity and permeability of the reservoir, and is the main contributor to the recoverable reserves, which is the basis and guarantee for the development of Gulong shale oil.
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Comprehensive Coordination Office of the Geological Society of China
2025,71(3):7103884-7103884, DOI: 10.16509/j.georeview.2023.12.001
Abstract:
Good sealing conditions are key to the preservation of helium resources, which play a crucial role in evaluating the exploration potential of helium resources in a certain area. Currently, the research on the capping characteristics of the helium reservoir is still in its infancy. In this paper, the characteristics of capping and sealing of helium reservoir are studied.Methods: In this paper, the capping mechanism and the relationship between macroscopic and microscopic characteristics of the capping layer and the sealing effect of helium were investigated by summarizing the capping characteristics of helium reservoirs all over the world. After that, the capping and sealing characteristics of the helium reservoir in Tarim Basin are analyzed.Results: The sealing mechanism of helium reservoir mainly includes three sealing mechanisms: physical property sealing, pressure sealing and concentration sealing. The sealing effect of cap rock on helium reservoir is affected by a series of microscopic characteristics (porosity, permeability, breakthrough pressure, median radius) and macroscopic characteristics (lithology, thickness, diagenesis, continuity, tectonics). The sealing ability of cap rock on helium gas is also different due to the different carrier gas types of helium reservoir. The sealing conditions of Hetianhe Block and Yakela Block are more favorable to the Gucheng Block, conventional methods for evaluating capping conditions of hydrocarbon reservoirs are not fully applicable to the assessment of capping conditions of helium resources.Conclusions: According to the relationship between the cap rock characteristics and the sealing efficiency of the helium reservoir summarized in this paper, the cap conditions of the helium reservoir can be preliminarily evaluated. The research on the method of accurately analyzing the cap conditions of the helium reservoir is still in the exploration stage and will be the focus of future work.
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2025,71(3):2025030000-2025030000, DOI:
Abstract:
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HOU Haihai, HE Qian, LIU Shujun, GAO Lianfeng, WANG Chongjing
2025,71(3):2025030001-2025030001, DOI: 10.16509/j.georeview.2025.05.012
Abstract:
As the most severe of the five major global extinction events in geological history, the Late Permian mass extinction led to the loss of approximately 81% of marine species and 75% of terrestrial species in the ecosystem. A systematic review of the extinction patterns and mechanisms at the Permian—Triassic boundary (PTB) holds significant practical importance for predicting the recurrence of large- scale extinction events.Methods: An analysis of the evolution of terrestrial plants, tetrapods, and marine organisms at the end of the Permian was conducted based on paleontological data from multiple global sections. Regarding the causes of the end- Permian mass extinction, factors such as ocean acidification, marine anoxia, ocean warming, sea- level fluctuations, ancient wildfire events, and weathering conditions were discussed.Results: The SLIP outbreak promoted the release of a large amount of greenhouse gases buried in the sediments of inland basins and continental shelves into the atmosphere, and the rapid global warming led to the land crisis in advance. Extreme dry weather promoted the frequent forest wildfires and the collapse of terrestrial ecosystems. The intensification of continental weathering caused a large number of debris to be injected into the ocean, resulting in serious eutrophication, hypoxia of submarine organisms, ocean acidification and disturbance of Marine paleoproductivity, etc., resulting in the occurrence of Marine extinction events. However, the lag of terrestrial extinction led to the end of the terrestrial crisis later than the Marine extinction event. Conclusions: The extinction of EPME species was characterized by regional, selective and phased extinction. The eruption of the Siberian Igneous Province (SLIP) is highly coupled with the EPME time, and SLIP and its associated series of secondary events are considered to be the main driving force of EPME and the main factor of delayed biological recovery. The duration, intensity and regional distribution of some secondary events, such as ocean hypoxia and sea water warming, are still controversial, and a single secondary event cannot independently support EPME, which is the result of the comprehensive superposition of multiple factors.
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HUANG Ming, LIU Lei, LIU Heng, ZHANG Yunfei, WEN Zhilin, HUANG Baoliang, ZHOU Weijian
2025,71(3):2025030002-2025030002, DOI: 10.16509/j.georeview.2025.05.035
Abstract:
The metallogenic mechanism of Shangshi spodumene- bearing pegmatite deposit, including the source of ore- forming materials and the process of lithium enrichment, remains for further investigation.Methods:In order to clarify the metallogenic mechanism such as the source of ore- forming materials and the process of lithium enrichment, the ore- forming mechanism is discussed based on geochemical characteristics of the major and trace element, Sr—Nd isotope of whole rock, as well as the SQI structure and geochemical characteristics of spodumene.Results: The baishawo two- mica monzogranite exhibits high content of Si2O, K2O and Al2O3, with A/CNK values ranging from 1.20 to 1.32, and relatively low Zr/Hf values (<25) and Nb/Ta values (<5), belongs to strongly peraluminous rocks and show S- type and highly evolved features. The spodumene pegmatites likely formed during the terminal stage of magmatic differentiation, where lithium concentrations reached saturation levels. Notably, the low εNd(t) values (-3.87 to -8.80) and Nd model ages (TDM2 range from 1.41Ga to 1.93Ga) of the baishawo two- mica monzogranite suggests that the rocks were likely sourced from the remelting of the Proterozoic crustal materials in South China. The high FeOT/(FeOT + MgO) ratios (0.85 ~ 0.87), obviously Ba—Sr—Eu negative anomalies, and low Cr and Co contents of the baishawo two- mica monzogranite imply a water- poor and reducing environment during formation. The Baishawo granite likely derived from partial melting of felsic clay- rich crustal sources under such conditions, generating lithium- enriched initial melts. Petrographic textures reveal spodumene—quartz intergrowths (SQI) along the margins of early- crystallized spodumene. The SQI structures potentially formed via petalite decomposition under changing P—T conditions during mineralization. Conclusions: Overlapping processes—partial melting of lithium- rich source rocks and extreme magmatic evolution—contributed to the formation of the Shangshi spodumene pegmatite deposit. Positive correlations between Sn—Ga and Fe—Mn contents in spodumene suggest that rare metals (Sn, Ga) may incorporate into the mineral lattice through Fe/Mn substitutions, while Fe—Al and Al—Si substitutions promote crystal growth and enhance metal enrichment.
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MA Fenling, WU Zhichun, JIANG Shuming, LI Hongda, GUO Fusheng, LI Hualiang, LIU Pinghua, LI Bin, JIN Wenlong
2025,71(3):2025030003-2025030003, DOI: 10.16509/j.georeview.2025.05.055
Abstract:
Digital geological mapping three- dimensional model is a new expression of regional geological survey results ( geological maps ). Compared with planar geological maps,it has better readability. In view of the limitations of the current mainstream explicit modeling methods,such as low modeling efficiency,high manual intervention and difficulty in model updating,this paper uses the digital geological mapping data of 1∶25,000 Shandang sheet in Jiangxi province to explore digital geological mapping implicit three- dimensional modeling method based on Leapfrog Geo software platform.Methods:Fast radial basis function ( FastRBF ) is used to quickly construct geological interfaces such as fault plane,Quaternary bottom interface and stratigraphic interface. According to the new and old relationship of the geological body,these geological interfaces are used to cut and fill the blank three- dimensional volume element model of the modeling area in turn,and the cut three- dimensional volume element model of the geological body is given attributes. The three- dimensional volume element model of all geological bodies is combined to generate the digital geological mapping three- dimensional model of Shandang sheet.Results:At the same time,in view of the difficulty in constructing complex geological models,a block modeling method is proposed. Aiming at the problem that sparse occurrence data cannot directly construct the Quaternary bottom interface,an explicit—implicit interactive modeling method is proposed.Conclusions:This modeling method realizes the high- precision and rapid construction of digital geological mapping three- dimensional model in Shandang sheet,showing a good application prospect.
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MENG Dongqing, CHEN Xiangzhi, LONG Chengtao, ZHANG Haijun, MA Haiquan
2025,71(3):2025030004-2025030004, DOI: 10.16509/j.georeview.2025.05.025
Abstract:
The investigation of mineral resources below accomplished constructions is a new work proposed in recent years. At present, a mature and perfect method has not yet been formed. The authors analyze and discuss the controversial issues in the investigation of mineral resources below accomplished constructions, and proposes a method to determine the status of mineral resources below accomplished constructions: Use the orthographic images combined with construction land type patches to determine the scope of construction land; Use the width of the safety belt of the highest-level building, the maximum empirical value of the rock movement angle, and the maximum burial depth of the ore body to calculate the maximum covered width of the construction, and the estimated range of resource reserves is the remaining. By simplifying disputes and complex problems and optimizing the conclusions of the investigation, the purpose of carrying out the investigation reasonably and efficiently is achieved. This paper introduces the practical experience of Beijing, and puts forward some suggestions for further optimizing the investigation method. And the article can provide references for the implementation of the investigation method of mineral resources below accomplished constructions.
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WANG Guoliang, XU Haiquan, CAO Jinshan, LI Shanping, GOU Mingliang, ZHENG Ying, YUAN Jinpeng, FENG Jianping, XU Shangping
2025,71(3):2025030005-2025030005, DOI: 10.16509/j.georeview.2025.05.045
Abstract:
The Zongwulongshan tectonic belt is located on the northeast edge of the Qinghai Tibet Plateau and is an important geological structural unit that connects the East Kunlun orogenic belt and the South Qilian orogenic belt.The results show that in recent years, the 1∶25000 regional geological and mineral surveys conducted in the region have made significant breakthroughs in lithium beryllium deposits, greatly enhancing basic geological research and exploration space.This article uses petrology, mineralogy, whole rock geochemistry, LA- ICP- MS zircon geochronology, and Lu—Hf isotope methods to study gneiss like diorite.The results showed that a total of 29 zircons identified 3 different age values:(1)There are eight measurement points with n(206Pb) /n(238U) concordant age data ranging from 563.4 ± 9.7Ma to 1116.6 ±11.0 Ma, representing the captured surrounding rocks or inherited early magmatic crystalline zircons during the intrusion process of the rock mass.(2) There are four measurement points,which represent the early magmatic events of the Early Paleozoic era. The n(206Pb)/n(238U)concordant age of zircons ranges from 521.1 ± 8.7 Ma to 534.6 ± 4.4 Ma, representing the captured or inherited early zircon ages.(3) There are sixteen analysis points with a concordant age value of n(206Pb)/n(238U), which is 512.9 ± 1.2Ma (MSWD)=0.80,n=16), indicating the crystallization age of the rock mass and representing the intrusion age of the rock mass in the Middle Cambrian. The Hf isotope results indicate that εHf(t) varies between -3.03 and -18.03, with an average value of -9.61. The two- stage model age (TDMC) ranges from 1678 Ma to 2617 Ma, suggesting that the granite originated from the remelting of ancient crust. The rock is relatively enriched in light rare earth elements and relatively depleted in heavy rare earth elements. The rock mass is characterized by high Si and Y, rich in Na2O+K2O, poor in Ca, low in Fe and Mg, and strong depletion of Sr, Eu, P and Ti, belonging to a typical A- type granite. Based on the comprehensive analysis of regional geological background, we believe that the gneiss like diorite in this area was formed in an active continental margin arc extensional environment where the original Tethys Ocean subducted southward. This discovery is of great significance for inverting the early Paleozoic tectonic evolution of the Zongwulong structural belt.
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WANG Xuepeng, SONG Weihua, LI Wenhui, WANG Weilong, CHEN Jingpeng, LIU Huan, YANG Yabin, ZHAO Jichu
2025,71(3):2025030006-2025030006, DOI: 10.16509/j.georeview.2025.05.032
Abstract:
The Ningjin buried uplift is rich in geothermal resources, and there are two geothermal wells with water temperatures exceeding 80 ℃, which have obvious geothermal anomalies. Identifying the genesis model of the heat source in this area is of great significance for geothermal exploration. Methods: In this study, gas geochemical methods were used to collect gas components and rare gas isotope samples for testing and analysis. The geochemical characteristics of geothermal gases and the origin of heat sources in the area were studied. Results: The results showed that the geothermal gas type in this area is N2 type, which is a geothermal resource type with deep circulation origin. This indicates that the geothermal resources in this area circulate and migrate in a relatively closed geological environment. The underground hot water mainly comes from atmospheric precipitation infiltration, and after heat conduction and convection heating, a low- temperature geothermal system is formed, which is less affected by mantle source heat; The volumn fraction of N2, O2, and CO2 components in geothermal gas stored in the area is not significantly correlated with well depth and water temperature, but mainly related to geological structural conditions, acidity and alkalinity of groundwater, and redox environment. Conclusions: The main heat sources in the region are the conduction of heat from the deep crust and upper mantle, and some deep faults connect karst thermal reservoirs. These faults play an important role in communicating and conducting magma heat sources from the deep crust and upper mantle, and form a good channel for underground heat flow. The sandstone thermal reservoir in the upper part of this area has a wide distribution range and good uniformity. The main source of heat is crustal; The karst heat controlled by faults has exposed fracture zones, connected underground heat source channels, and formed a high- temperature hot water type low- temperature geothermal resource system.
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ZHANG Lin, ZHAO Jing, XIE Shiqiang, LIANG Jinlong, CHEN Youliang, GUO Jia, WANG Xuemei, LIANG Song
2025,71(3):2025030007-2025030007, DOI: 10.16509/j.georeview.2025.05.015
Abstract:
The Daqiao gold deposit is one of the most representative super- large gold deposits in the western Qinling Mountains, China. However, the genesis of the Daqiao deposit has remained controversial. Pyrite is one of the major gold- bearing minerals of the deposit, and its mineral chemistry and in- situ sulfur isotopes can be important indicators for the genesis of the Daqiao deposit. Methods: This study presents detailed mineralogical analyses on the pyrite by using electron probe micro- analyzer (EPMA) and nanometer- scale secondary ion mass spectroscopy (Nano- SIMS).Results: Petrographic observations and backscattered electron images show that the pyrite collected from the Daqiao deposit consists of framboidal pyrite, euhedral pyrite, subhedral—anhedral pyrite, and zonal pyrite. The zonal pyrite is composed of two generations (namely core and overgrowth), corresponding to the two hydrothermal activities. Electron probe microanalysis proves that except for the framboidal pyrite, the euhedral pyrite, subhedral—anhedral pyrite, and zonal pyrite are characterized by Co/Ni ratio greater than 1 and ΔFe and ΔS less than 1, typical of hydrothermal pyrite. In particular, their (Fe+S) and As contents are well consistent with magmatic—hydrothermal pyrite from orogenic gold deposits elsewhere. Au—As correlation analysis and Nano- SIMS elemental mapping support the occurrence of Au nanoparticles within the lattice of the pyrite, which is resultant of the interactions between the pre- existing pyrite and ore- forming fluid. Nano- SIMS in- situ sulfur isotopic results show that the framboidal pyrite contains an extremely negative δ34S V- CDT value (-20.6‰ ~ -25.5‰), resulting from the bacterial sulfate reduction. Meanwhile, the δ34SV- CDTvalue of the core of the zoned pyrite ranges from +0.8‰ to +2.8‰, similar to mantle- derived magmatic sulfur. The δ34S V- CDT value of the overgrowth ranges from +8.0‰ to +17.7‰, consistent with that of magmatic rocks exposed in the western Qinling Mountains. It suggests that the latter also originated from the magmatic—hydrothermal fluids, probably with a mixture of other sulfur sources, for example, sedimentary sulfur. The difference in the S isotopes of these two- stage magmatic—hydrothermal fluids might be related to the natures of their parent magmas. Conclusion:Accordingly, the Daqiao gold deposit should be an orogenic gold deposit, which has a genetic affinity with the magmatic—hydrothermal fluids.
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ZHAO Wanzhu, CHENG Guangguo, WANG Guanhua, SONG Dongwei, LI Jing, LIU Yang
2025,71(3):2025030008-2025030008, DOI: 10.16509/j.georeview.2025.05.021
Abstract:
Toad dress the instability of geothermal detection using single phase thermal infrared remote sensing technology, this paper proposes a geothermal anomaly detection method based on multi- temporal thermal infrared remote sensing geothermal units.Methods: First, the temperature anomaly region was extracted from the global threshold and geothermal unit block thresholdbased on the geothermal inversion information of Landsat- 8 remote sensing image data. Subsequently, the areas of geothermal anomaly were detected through the principal component analysis of the abnormal ground temperature in winter from 2017 to 2021. Finally, a comprehensive analysis was conducted to delineate the geothermal anomaly range by combining these with the composite information of fault structure, DEM, and land cover. Results: A geothermal anomaly detection method based on multi- temporal Landsat- 8 satellite images was proposed to delimit 10 geothermal targets in the research area of Tangyin Fault Depression (Anyang segment). The results are compared with the geothermal locations obtained from shallow water temperature logging data in the field. The two methods have a high consistency in delineating geothermal anomaly areas, thus verifying the reliability of the method proposed.Conclusion:The experiment shows that compared to single- phase thermal infrared remote sensing, the proposed method is better for geothermal anomaly detection as it can eliminate the instabilities incurred in the former by integrating multi- temporal information. This is conducive to improving the accuracy and reliability of geothermal anomaly extraction by thermal infrared remote sensing technology.
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ZHU Mengyuan, MAO Lei, HE Qing, LI Shutong, ZHANG Shukang, DONG Xuyang, Li Yonghui
2025,71(3):2025030009-2025030009, DOI: 10.16509/j.georeview.2025.05.022
Abstract:
Dinosaur eggs in Anhui province are mainly preserved in Xiuning Basin and Qianshan Basin, and there are no taxonomic description in Xuancheng Basin. Dinosaur eggs and eggshells from the Upper Cretaceous Xuannan Formation near Qingyijiangnan Avenue, Xuanzhou District, Xucheng city are the first report in Xuancheng Basin, which are important for the stratigraphic division and correlation of the K—T boundary. Dinosaur eggs in this paper were analyzed by macrostructural measurement and microstructural observation. Results: Results show that these eggs are elongate in shape (the length is more than 100mm and width is 70mm). Chain or ridge ornamentations are distributed on the outer surface and eggshell thicknesses varies between 1.10 mm and 1.80 mm. The boundary between the cone layer and the columnar layer is nearly straight, and the ratio between them is 1∶4~1∶3. The radial microstructures in the cone layer are arranged closely and pore are few with erect shape.Conclusions: These dinosaur eggs are belonged to Elongatoolithus andrewsi in Elongatoolithidae, which are the first detailed taxonomic record in the Xuancheng Basin, southern Anhui Province. These eggs are mainly preserved in the Upper Cretaceous Xuannan Formation. The studies of oospecies classification and future geochemistry provide important basic data for the dinosaur extinctions at the K—T boundary.
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XIE Xingyou, GAO Junbo, SU Te, FENG Kaiyou, LIU Mingmin, PENG Qiaoliang, YAO Xicai, SHEN Hongqian
2025,71(3):2025030010-2025030010, DOI: 10.16509/j.georeview.2025.05.085
Abstract:
Through geological and elemental geochemical studies, this research identifies hydrothermal sedimentary evidence of the Tianxiong manganese deposit in central Hunan, aiming to provide supplementary insights for metallogenic theory and exploration direction of manganese resources in this region.Methods: Based on petrographic and mineralogical identification, major and trace element analyses of manganese ore beds and their overlying/underlying country rock samples, this study systematically investigates the petrographic characteristics, mineralogical features, and geochemical composition of manganese ores.Results: 1. The predominant manganese-bearing minerals in the Tianxiong Manganese Deposit of central Hunan are rhodochrosite and manganocalcite. 2. Genetic discrimination indicators—including SiO?/Al?O?, Al/(Al+Fe+Mn), Co/Zn-(Cu+Co+Ni), Fe/Ti, Y/Ho diagrams, and the positive Eu anomaly observed in ores—collectively demonstrate that the ore—forming materials of the Tianxiong Deposit were likely derived from submarine hydrothermal systems. 3. Geochemical proxies such as Mn/Fe, V/(V+Ni), and δCe ratios in the manganese-bearing sequences suggest an overall suboxic-reducing depositional environment within a shallow marine facies.Conclusions: The Tianxiong manganese deposit in central Hunan and the Songtao manganese ore cluster in northeastern Guizhou may share similar metallogenic conditions characterized by deep-seated manganese-bearing fluid exhalative sedimentation. Building upon the exploration research framework of the "Datangpo-type" manganese deposits in northeastern Guizhou, further investigations should be prioritized to achieve new breakthroughs in manganese exploration within this region.
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XIONG Canjuan, YANG Ruidong, GAO Junbo, CHEN Jiyan, JANG Yuan, LI Zhi, PENG Rou, GAO Chuanqian, PANG Yuyu
2025,71(3):2025030011-2025030011, DOI: 10.16509/j.georeview.2025.05.075
Abstract:
Phosphorite, as a vital non-metallic mineral resource, is widely utilized in various fields, including agriculture, industry, and environmental protection. The northeastern Yunnan region, located on the southwestern margin of the Yangtze Craton, is a key area for the distribution of phosphorite resources. Consequently, research on its ore-forming processes holds significant academic and economic value. This review highlights the research progress on the metallogenic geological background, material sources, and ore-forming mechanisms of Cambrian Meishucun period phosphorite deposits in northeastern Yunnan. It is generally accepted that the phosphate deposits in northeastern Yunnan primarily formed in shallow marine carbonate platforms and platform sag basins. However, there remains ongoing debate regarding the specific depositional paleogeography and paleoenvironment. Several viewpoints exist concerning the sources of ore-forming materials, which include terrestrial materials, biogenic phosphorus, seawater, and deep-seated hydrothermal fluids. The main ore-forming mechanisms identified are biogenic phosphogenesis, marine hydrothermal deposition, and upwelling currents. Despite extensive studies on the genesis of phosphorite, no consensus has yet been reached. Controversies persist regarding the metallogenic background, material sources, and ore-forming mechanisms, which have hindered the development of regional metallogenic models. Future research should focus on in situ microstructural analysis combined with various geochemical methods to further explore the genesis mechanisms and paleo-oceanic environment of phosphorite in northeastern Yunnan. This will help establish a comprehensive metallogenic model for the region, contributing to phosphorite resource exploration and development, as well as advancing the study of the metallogenic system of the Yangtze Craton.
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2025,71(3):2025030012-2025030012, DOI: 10.16509/j.georeview.2025.05.065
Abstract:
The first two decades of the 20th century witnessed the budding and vigorous development of China's geological undertakings. During this period, China's geological science, which originated from the West, gradually established its own theoretical framework. China cultivated its first group of geological professionals independently during this time, and they swiftly developed into the mainstay of domestic geological surveys. ,Tan Xichou(谭锡畴,Tan H. C. ), a geologist and mineral deposit expert, was a representative figure. Between 1915 and 1924, Tan Xichou conducted intensive geological investigations in Shandong, leaving behind 12 volumes of highly valuable geological records and completing a number of academic papers, most of which have not yet been utilized in historical research. Based on these precious historical geological records, a systematic review of Tan Xichou's experiences during his study, internship, and early career stages is carried out. A profound analysis of the significance of his achievements in Shandong is also made, to observe the development process of Tan Xichou's personal academic ability and the development trajectory of China's early geological and mineral resources undertakings from these aspects.
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JIANG Zhenning, ZHU Yueqi, ZHANG Yang, ZHENG HouYi
2025,71(3):2025030013-2025030013, DOI: 10.16509/j.georeview.2025.05.001
Abstract:
Phosphate rock is an important chemical raw material and agricultural mineral resource, serving as a strategic mineral resource in China. Studying the supply-demand situation of phosphate resources and proposing corresponding countermeasures is of great significance for ensuring phosphate resource security and even national food security. China’s phosphate resources are characterized by abundant low-grade ores, scarce high-grade ores, numerous difficult-to-process ores, and few easily-processable ores. In recent years, China has maintained its position as the world’s largest producer of phosphate rock and the top consumer. In 2022, China’s phosphate reserves stood at 3. 69 Gt, ranking second globally.Methods:The authors employed statistical analysis methods to systematically summarize China’s phosphate resource reserve characteristics, production volumes, consumption levels, and price trends. A system dynamics model was also established to forecast China’s phosphate resource demand from 2022 to 2032. Results:The results indicate that demand will continue to grow moderately through 2032,the supply will shift from exceeding demand to falling short of demand in 2027. Over the past decade, China’s reserve-to-production ratio for phosphate has consistently remained below 40 a, reaching 35. 2 a in 2022-far below the global average-highlighting severe over exploitation of resources. Conclusions: Therefore, protecting phosphate resources requires immediate action. Recommendations include: increasing investment in high-grade phosphate exploration to enhance resource security; strengthening comprehensive utilization of medium-low grade ores and tailing to improve resource efficiency; and encouraging enterprises to “go global” through industrial layout optimization, establishing overseas phosphate supply bases to ensure sustainable resource utilization.
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NING Shuzheng, ZHANG Li, XU Xiaotao, QIAO Junwei, ZHANG Jianqiang, ZOU Zhuo, HUANG Shaoqing
2025,71(3):2025030014-2025030014, DOI: 10.16509/j.georeview.2025.05.031
Abstract:
As a coal resource with special purposes, oil- rich coal has an important position in the coal deep processing industry because of its high tar yield. Through the systematic review of China’s oil- rich coal resources, the distribution characteristics of China’s oil- rich coal resources and their development and utilization potential are deeply discussed. It is divided into six oil- rich coal areas: Shanxi, Shaanxi, Inner Mongolia, Ning Xia, Hebei, Shandong, Anhui, Xinjiang, Inner Mongolia, Ganqing and Yunnan, and the key information such as geographical distribution, geological characteristics, coal seam development and tar yield of each region are analyzed in detail. In terms of the prospect of the development and utilization of oil- rich coal, China’s oil- rich coal resources have great potential, and their development and utilization are of great strategic significance for alleviating China’s dependence on foreign oil and gas resources and promoting the transformation and upgrading of the coal industry. With the upgrading of the coal deep processing industry and the proposal of carbon neutrality goal, the quality and grading utilization of oil- rich coal has become an important way for coal transformation and development. In terms of the utilization technology of oil- rich coal, both surface and underground utilization technologies have good development prospects. In the future, we should continue to strengthen the exploration and development of oil- rich coal resources, and at the same time promote the research and practical exploration of oil- rich coal quality and grading utilization technology. Through technological innovation and industrial upgrading, we will realize the efficient, clean and low- carbon development and utilization of oil- rich coal resources, and make important contributions to China’s energy security and sustainable development
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YU Yazhou, WANG Di, LIU Yibin, WANG Xingping, WU Zhiping
2025,71(3):2025030015-2025030015, DOI: 10.16509/j.georeview.2025.05.011
Abstract:
The distribution of hydrocarbon resources in the paleogene strata in Tanhai area, the Jiyang Depression, Bohai Bay Basin, is affected by the development characteristics of fault network. In this paper, we hope to define the plane geometric features of the fault network and establish the relationship between the geometric features of the fault network and the oil and gas distribution.Methods:Based on structural interpretation of seismic data, fractal and topological methods are used to analyze the development characteristics of the fault network on the plane.Results:On the T6 interface, the high value area of fractal dimension and topologicalvalue spread out in NW, with the characteristics of high in south and low in north; At the T2 interface, the NNE of the high value area of fractal dimension and topological value spreads out in the direction, which is high in the east and low in the west. On T1 interface, the NE of the high value area of fractal dimension and topological value spreads out in the direction, which is high in the east and low in the west. The fractal dimension and topological value are higher along the existing faults, especially in the intersection area of multi-directional faults and strike-slip fault overlapping area. The reservoir is mainly developed in the parts with complex fault development with high fractal dimension and high topological value.Conclusions:The fractal characteristics and topological structure of fault network system are affected by preexisting faults, regional stresses and strike-slip faults. Reservoir development is influenced by the fractal characteristics and topological structure of fault network system. The regions with high topological values are connected with faults of different order, which improves the connectivity of the fault network system. A large number of secondary faults are developed in the high fractal dimension region, which is conducive to the formation of traps.
Volume 71,2025 Issue 3
Theme paper
Scolarly discussion
Scientific review
Reserch progress
Correspondence·Reference·News report·Introduction to new book
Theme paper
Publish online-I
Volume 71,2025 Issue 3
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A new sauropterygian (Reptilia: Sauropterygomorpha), Spatulidentatus breviceps gen.et sp. nov. from the Middle Triassic of SW China
YANG Mei, QIN Yanjiao, ZHANG Yinfeng, HE Xiao, LI Ji
Abstract:
This paper briefly reports a new genus and species of Sauropterygia, Spatulidentatus breviceps, from the Upper Member of the Middle Triassic Guanling Formation in the border area between Yunnan and Guizhou in Southwest China. The new species can be diagnosed by following characteristics: a mall head, accounting for 5% of the total body length; spatulate teeth in both upper and lower jaws; elongated neural spines in dorsal and tail region; a well - developed scapular dorsal wing; a sub-oval coracoid; and a distinctly expanded distal humerus with well-developed condyle. Preliminary comparative analysis shows that the new species may have a relatively close relationship with the basal groups of Sauropterygia, such as Placodontia and Atopodentatus.
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Chemical mineral and Nano-SIMS in-situ S isotope of pyrite from the Daqiao gold deposit, Gansu Province: Implications for the genesis of the deposit
lin zhang, jing zhao, shiqiang xie, jinlong liang, youliang chen, jia guo, xuemei wang, song liang
Abstract:
The Daqiao gold deposit is one of the most representative super-large gold deposits in the western Qinling Orogen, China. However, the genesis of the Daqiao deposit has remained controversial. Pyrite is one of the major gold-bearing minerals of the deposit, and its mineral chemistry and in-situ sulfur isotopes can be important indicators for the genesis of the Daqiao deposit. This study presents a detailed mineralogical analyses on the pyrite by using electron probe micro-analyzer (EPMA) and nanometer-scale secondary ion mass spectroscopy (Nano-SIMS). Petrographic observations and backscattered electron images show that the pyrite collected from the Daqiao deposit consists of framboidal pyrite, euhedral pyrite, subhedral-anhedral pyrite, and zonal pyrite. The zonal pyrite is composed of two generations (namely core and overgrowth), corresponding to the two hydrothermal activities. Electron probe microanalysis proves that except for the framboidal pyrite, the euhedral pyrite, subhedral-anhedral pyrite, and zonal pyrite are characterized by Co/Ni ratio greater than 1 and δFe and δS less than 1, typical of hydrothermal pyrite. In particular, their (Fe+S) and As contents are well consistent with magmatic-hydrothermal pyrite from orogenic gold deposits elsewhere. Au-As correlation analysis and Nano-SIMS elemental mapping support the occurrence of Au nanoparticles within the lattice of the pyrite, which is resultant of the interactions between the pre-existing pyrite and ore-forming fluid. Nano-SIMS in-situ sulfur isotopic results show that the framboidal pyrite contains an extremely negative δ34S value (–20.6 ‰ ~–25.5 ‰), resulting from the bacterial sulfate reduction. Meanwhile, the δ34S value of the core of the zoned pyrite ranges from +0.8 ‰ to +2.8 ‰, similar to mantle-derived magmatic sulfur. The δ34S value of the overgrowth ranges from +8.0 ‰ to +17.7 ‰, consistent with that of magmatic rocks exposed in the western Qinling Orogen. It suggests that the latter also originated from the magmatic-hydrothermal fluids, probably with a mixture of other sulfur sources, for example, sedimentary sulfur. The difference in the S isotopes of these two-stage magmatic-hydrothermal fluids might be related to the natures of their parent magmas. Accordingly, the Daqiao gold deposit should be an orogenic gold deposit, which has a genetic affinity with the magmatic-hydrothermal fluids.
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- U-Pb ages, geochemistry, and Hf isotope characteristics of zircon from LA-ICP-MSWANG guoliang 1, 2,,3 XU haiqua 1, 2, 3, CAO jinshan1, 2, LI Shanping1, 2, 3, GOU mingliang1, 2, ZHENG Ying1, 2, YUAN jinpeng1, 2, FENG jianping 1, 2, XU Shangping 1, 2
Abstract:
The Zongwulongshan tectonic belt is located on the northeast edge of the Qinghai Tibet Plateau and is an important geological structural unit that connects the East Kunlun orogenic belt and the South Qilian orogenic belt. It is one of the key areas for the formation of PbZnAg, Cu, Au and other polymetallic mineralization zones, as well as rare and rare earth minerals, with great potential in Qinghai Province. In recent years, the 1:25000 regional geological and mineral survey conducted in the region has made significant breakthroughs in regional basic geology and mineral resources, especially lithium beryllium deposits, greatly improving the level of basic geological research and exploration space in the region. This article selects the gneiss like diorite granite as the research object, and attempts to study it from the perspectives of petrology, mineralogy, geochemistry, and [1]chronology using first-hand field data. Using LA-ICP-MS zircon micro dating technique, a total of 29 zircons were selected from the gneiss like diorite granite. Among the ages determined by the 29 zircons, (1) There are 9 measurement points with 206Pb -238U harmonic age data ranging from (563.4 ± 9.7) Ma to (1116.6 ± 11.0) Ma, representing the captured surrounding rocks or inherited early magmatic crystalline zircons during the intrusion process of the rock mass. (2) The- 206Pb -238U harmonious age of zircon at one measuring point (point 22) is (453.7 ± 7.2) Ma, which may represent a regional metamorphic event in the area. (3) There are four measurement points, which represent the early magmatic events of the Early Paleozoic era. The 206Pb -238U harmonious age of zircons ranges from (521.1 ± 8.7) Ma to (534.6 ± 4.4) Ma, representing the captured or inherited early zircon ages. (4) There are 16 analysis points with a harmonic age value of 206Pb -238U, which is 512.9 ± 1.2Ma (MSWD=0.80, n=16), indicating the crystallization age of the rock mass and representing the intrusion age of the rock mass in the Middle Cambrian. The Hf isotope results indicate that ε Hf (t) varies between -3.03 and -18.03, with an average value of -9.61. The two-stage model age (TDMC) ranges from 1678 Ma to 2617 Ma, suggesting that the granite originated from the remelting of ancient crust. The rock is relatively enriched in light rare earth elements and relatively depleted in heavy rare earth elements. The rock mass is characterized by high Si and Y, rich in Na2O+K2O, poor in Ca, low in Fe and Mg, and strong depletion of Sr, Eu, P, and Ti, belonging to a typical A-type granite. Based on the comprehensive analysis of regional geological background, we believe that the gneiss like diorite in this area was formed in an active continental margin arc extensional environment where the original Tethys Ocean subducted southward. This discovery is of great significance for inverting the early Paleozoic tectonic evolution of the Zongwulong structural belt.
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Metallogenic mechanism of Shangshi spodumene pegmatite deposits in Lianyunshan area, Northeast Hunan Province: from whole rock and spodumene geochemical constraints
HUANG Ming, LIU Lei, LIU Heng, ZHANG Yunfei, WEN Zhilin, HUANG Baoliang, ZHOU Weijian
Abstract:
Objectives: The source of ore-forming materials and the process of lithium enrichment in the newly discovered Shangshi spodumene pegmatite type deposit are still unclear. Methods: In order to clarify the ore-forming mechanism such as the source of ore-forming materials and the process of lithium enrichment, the ore-forming mechanism is discussed based on the major and trace of whole rock, Sr-Nd isotope characteristics and the SQI structure and geochemical characteristics of spodumene. Results: The two-mica monzonitic granite has A high content of Si2O, K2O and Al2O3. The A/CNK value (1.20-1.32), lower Zr/Hf value (< 25) and Nb/Ta value (< 5) indicate that it is a peraluminous rock with the characteristics of S-type granite and high differentiation. The lower εNd(t) value (-3.87 - -8.80) and Nd T2DM age (14.1 - 19.3 Ga) of the Baishawo two-mica monzonite granite reveal that it may be derived from the remelting of Proterozoic crustal materials in South China. The relatively high εNd(t) value (-3.87), with an Nd T2DM age of 14.1Ga, may indicate a younger crustal remelting. The high FeOT/ (FeOT + MgO) values (0.85-0.87), the obvious negative anomaly of Ba-Sr-Eu and the lower content of Cr and Co demonstrate that the granite was formed in a water-poor reduction environment. Isotopic characteristics indicate that the variation range of (87Sr/86Sr)i (0.694881 - 0.707620) of the spodumene pegmatite is between the Baishawo two-mica monzonite granite (0.721520 - 0.724873) and the two-mica schist (0.680817 - 0.695009). The results shows that the Sr in ore-forming fluid may be the result of mixing of Sr in rock mass and Sr in surrounding rock. The petrographic structure shows that Spodumene-quartz intergrowth (SQI structure) is not evenly distributed along the edges of spodumene that crystallized earlier in the magmatic system. The SQI structure may be the product of the decomposition of petalite and formed under the influence of the change of temperature and pressure conditions in the metallogenic environment. Conclusions: The formation of the Shangshi spodumene pegmatite deposit may be influenced by three factors: lithium ore-rich magma formation in the source area, further enrichment of lithium in the process of magma differentiation, and extraction of rare metal elements from the surrounding rock by magma/magma fluid.
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Geochemical evidence of thermal water origin of Nanhua Period Tianxiong manganese deposit in Lianyuan, central Hunan Province
xiexingyou, gaojunbo, sute, panwen, fengkaiyou, pengqiaoliang, yuanliangjun, liumingmin, yaoxicai, shenhongqian
Abstract:
The Tianxiong manganese deposit is one of the representative " Datangpo type " manganese deposits in Lianyuan area of central Hunan Province. On the basis of field geological survey andcombined with previous research results, this article conducts a detailed analysis of the geological and geochemical characteristics of the rhodochrosite layer and its roof and floor surrounding rock. The results show that the ore structure of Tianxiong manganese deposit is mainly stripe-banded, and the ore texture is mainly unequal crystal silt debris structure and micro-mud crystal algae pellet structure, and the main ore minerals are rhodochrosite and manganocalcite. The contents of MnO, CaO and MgO are higher while TiO2, SiO2 and Al2O3 are lowerin the rhodochrosite layer than those in the surrounding rock of the roof and floor. Compared with the abundance of continental crust, the average content of trace elements in manganese bearing rock series is relatively enriched with only Pb ,etc. elements, while Zr, Ta, and Cr are severely depleted. The SiO2 / Al2O3 ratio indicates that the manganese source is not normal terrestrial source. By calculating the ratios of Al / ( Al + Fe + Mn ), ( Fe + Mn ) / Ti, Fe / Ti, Y / Ho, Nb / Ta and drawing Fe-Mn- ( Cu + Co + Ni ) × 10, Co / Zn- ( Cu + CO + Ni ) triangle diagrams, the results show that the rhodochrosite layer has hydrothermal sedimentary characteristics. The ratios of Mn / Fe, Sr / Ba, Th / U and V / ( V + Ni ) indicate that the sedimentary environment of rhodochrosite is shallow sea and sub-oxidation-reduction environment. The δEu value anomaly, La / Ce ratio, ΣREE value, and ΣLREE / ΣHREE ratio of the rhodochrosite layer all reflect that the manganese deposition process is affected by hot water activity.
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Discussion on investigation methods of mineral resources below accomplished constructions——Taking the practice of Beijing as an example
Meng Dongqing, Chen Xiangzhi, Long Chengtao, Zhang Haijun, Ma Haiquan
Abstract:
The investigation of mineral resources below accomplished constructions is a new work proposed in recent years. At present, a mature and perfect method has not yet been formed. The authors analyze and discuss the controversial issues in the investigation of mineral resources below accomplished constructions, and proposes a method to determine the status of mineral resources below accomplished constructions: Use the orthographic images combined with construction land type patches to determine the scope of construction land; Use the width of the safety belt of the highest-level building, the maximum empirical value of the rock movement angle, and the maximum burial depth of the ore body to calculate the maximum covered width of the construction, and the estimated range of resource reserves is the remaining. By simplifying disputes and complex problems and optimizing the conclusions of the investigation, the purpose of carrying out the investigation reasonably and efficiently is achieved. This paper introduces the practical experience of Beijing, and puts forward some suggestions for further optimizing the investigation method. And the article can provide references for the improvement and development of the investigation method of mineral resources below accomplished constructions.
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H.C.T’AN and Geological Survey of Shandong Province:1915-1924-- Research on Geological Archives
Abstract:
The first two decades of the 20th century witnessed the budding and vigorous development of China"s geological undertakings. During this period, China"s geological science, which originated from the West, gradually established its own theoretical framework. China cultivated its first group of geological professionals independently during this time, and they swiftly developed into the mainstay of domestic geological surveys. H.C.T’AN(谭锡畴,Tan Xichou), a geologist and mineral deposit expert, was a representative figure. Between 1915 and 1924, H.C.T’AN conducted intensive geological investigations in Shandong, leaving behind 12 volumes of highly valuable geological records and completing a number of academic papers, most of which have not yet been utilized in historical research. Based on these precious historical geological records, a systematic review of H.C.T’AN"s experiences during his study, internship, and early career stages is carried out. A profound analysis of the significance of his achievements in Shandong is also made, so as to observe the development process of H.C.T’AN"s personal academic ability and the development trajectory of China"s early geological and mineral resources undertakings from these aspects.
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Exploration of implicit three-dimensional modeling method for digital geological mapping—Taking 1 : 25,000 Shandang sheet as an example
MaFenling, WuZhichun, JIANG Shuming, LI Hongda, GUO Fusheng, LI Hualiang, LIU Pinghua, LI Bin, JIN Wenlong
Abstract:
Digital geological mapping three-dimensional model is a new expression of regional geological survey results ( geological maps ). Compared with planar geological maps,it has better readability. In view of the limitations of the current mainstream explicit modeling methods,such as low modeling efficiency,high manual intervention and difficulty in model updating,this paper uses the digital geological mapping data of 1:25,000 Shandang sheet in Jiangxi province to explore digital geological mapping implicit three-dimensional modeling method based on Leapfrog Geo software platform. Fast radial basis function ( FastRBF ) is used to quickly construct geological interfaces such as fault plane,Quaternary bottom interface and stratigraphic interface. According to the new and old relationship of the geological body,these geological interfaces are used to cut and fill the blank three-dimensional volume element model of the modeling area in turn,and the cut three-dimensional volume element model of the geological body is given attributes. The three-dimensional volume element model of all geological bodies is combined to generate the digital geological mapping three-dimensional model of Shandang sheet. At the same time,in view of the difficulty in constructing complex geological models,a block modeling method is proposed. Aiming at the problem that sparse occurrence data cannot directly construct the Quaternary bottom interface,an explicit-implicit interactive modeling method is proposed. This modeling method realizes the high-precision and rapid construction of digital geological mapping three-dimensional model in Shandang sheet,showing a good application prospect.
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The Research Progress on the Ore-forming Processes of Phosphorite during the Meishucun Period in Northeast Yunnan
Abstract:
Phosphorite, as a vital non-metallic mineral resource, is widely utilized in various fields, including agriculture, industry, and environmental protection. The northeastern Yunnan region, located on the southwestern margin of the Yangtze Platform, is a key area for the distribution of phosphorite resources. Consequently, research on its ore-forming processes holds significant academic and economic value. This review highlights the research progress on the metallogenic geological background, material sources, and ore-forming mechanisms of Cambrian Meishucun period phosphorite deposits in northeastern Yunnan. It is widely accepted that these phosphorite deposits primarily formed in sedimentary basins and depression zones. However, there remains ongoing debate regarding the specific depositional paleogeography and paleoenvironment. Several viewpoints exist concerning the sources of ore-forming materials, which include terrestrial materials, biogenic phosphorus, seawater, and deep-seated hydrothermal fluids. The main ore-forming mechanisms identified are biogenic phosphogenesis, marine hydrothermal deposition, and upwelling currents. Despite extensive studies on the genesis of phosphorite, no consensus has yet been reached. Controversies persist regarding the metallogenic background, material sources, and ore-forming mechanisms, which have hindered the development of regional metallogenic models. Future research should focus on in situ microstructural analysis combined with various geochemical methods to further explore the genesis mechanisms and paleo-oceanic environment of phosphorite in northeastern Yunnan. This will help establish a comprehensive metallogenic model for the region, contributing to phosphorite resource exploration and development, as well as advancing the study of the metallogenic system of the Yangtze Platform.
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Tourism resources and economic growth:Evidence from global geoparks
WANG Meng, WANG Bo-lin, HE Jia-xin
Abstract:
This article utilizes a natural experiment provided by global geoparks to construct a difference-in-difference (DID) model to identify the impact of tourism resources on economic growth. Regression analysis based on panel data of 284 cities in China from 2003 to 2020 shows that global geoparks have significantly driven economic growth, i.e., cities with global geoparks have an average increase of 9.7% in the growth rate of light brightness on the ground average compared to cities without global geoparks. This result remains robust in a series of analyses, including change time lag, adding control variables, and selecting a subsample. Heterogeneity analysis reveals that the positive effect of global geoparks on economic growth is stronger in cities without tourism brand certifications, but there are no significant differences between cities with different transportation infrastructures. The conclusions of this paper will provide insights for the development tourism resources of policy-making.
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Comparative Study between cyclostratigraphy and Magnetostratigraphy of Cenozoic in Amami-Sankaku Basin
FU Wenzhao, Zhang Ping, GAO Lianfeng, Maffione Marco, YANG Yu, HouHaihai, ZHANG Zhenguo, MA Ruixue
Abstract:
The International Ocean Discovery Program (IODP)351 expedition drilled unconsolidated deep-sea sediment sequences in the Amami Sankaku Basin of the Philippine Sea, establishing an accurate age model through magnetostratigraphic methods. This study conducted cyclostratigraphic analysis on the 0–127.58m interval of Site U1438 in the Amami Sankaku Basin, revealing discrepancies between cyclostratigraphic and magnetostratigraphic results. Cyclostratigraphic analysis identified well-preserved Milankovitch cycles in three intervals (0–127.58m, 0–80m, and 0–50.28m). However, the thickness of the 405ka sedimentary cycles in the 0–127.58m interval exhibited significant deviations compared to other intervals. By comparing cyclostratigraphic and magnetostratigraphic ages, it was observed that ages aligned closely above 83m, but diverged progressively below this depth. This suggests unstable deposition rates within the 83–113m interval. Integrating prior research, we propose that tectonic events in the Amami Sankaku Basin and adjacent regions during the 6–12 Ma period significantly influenced deposition rates, leading to pronounced variations in Milankovitch cycle thickness during this interval.
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Analysis of geochemical characteristics of thermal reservoir gas in the Ningjin Subuplift
Wang Xuepeng, Song Weihua, Li Wenhui, Wang Weilong, Chen Jingpeng, Liu Huan, Yang Yabin, Zhao Jichu
Abstract:
The Ningjin subuplift is rich in geothermal resources, and there are two geothermal wells with water temperatures exceeding 80 ℃, which have obvious geothermal anomalies. Identifying the genesis model of the heat source in this area is of great significance for geothermal exploration. In this study, gas geochemical methods were used to collect gas components and rare gas isotope samples for testing and analysis. The geochemical characteristics of geothermal gases and the origin of heat sources in the area were studied. The results showed that the geothermal gas type in this area is N2 type, which is a geothermal resource type with deep circulation origin. This indicates that the geothermal resources in this area circulate and migrate in a relatively closed geological environment. The underground hot water mainly comes from atmospheric precipitation infiltration, and after heat conduction and convection heating, a low-temperature geothermal system is formed, which is less affected by mantle source heat; The content of N2, O2, and CO2 components in geothermal gas stored in the area is not significantly correlated with well depth and water temperature, but mainly related to geological structural conditions, acidity and alkalinity of groundwater, and redox environment. The main heat sources in the region are the conduction of heat from the deep crust and upper mantle, and some deep faults connect karst thermal reservoirs. These faults play an important role in communicating and conducting magma heat sources from the deep crust and upper mantle, and form a good channel for underground heat flow. The sandstone thermal reservoir in the upper part of this area has a wide distribution range and good uniformity. The main source of heat is crustal; The karst heat controlled by faults has exposed fracture zones, connected underground heat source channels, and formed a high-temperature hot water type low-temperature geothermal resource system.
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Metallogenic regularity and prospecting prediction of Cambrian sedimentary barite deposits in Southeast Guizhou
gaojunbo, LI Yonggang, LI Shibin, HE Shanli, YANG Ruidong, XIE Xingyou, LIU Ling, LI Xinzheng, LUO Bangliang, WANG Wenjie, RAO Hongjuan, YANG Guilong
Abstract:
The Early Cambrian witnessed an explosive mineralization event of barite, forming a series of large to super?large deposits in southeastern Guizhou, represented by the Dahebian barite deposit. These deposits are connected to the Cambrian barite metallogenic belt at Gongxi, Hunan Province, collectively constituting a crucial component of the Jiangnan barite metallogenic belt?the most concentrated barite resource region in China, with cumulative barite reserves of approximately 240 million tonnes, demonstrating global representativeness. The Cambrian barite deposits in southeastern Guizhou exhibit widespread distribution, high resource concentration, and clustered occurrences. The three most prolific barite enrichment zones include: 1) Dahebian?Gongxi (primary enrichment zone), 2) Meilang?Yajin, and 3) Laowenxi?Bingxi. Systematic comparisons have revealed distinct differences among these zones in deposit scale, sedimentary sequences, ore textures/structures, and elemental/isotopic compositions, likely attributable to differential material supply paleo?seawater chemistry, and microbial activities in ore?controlling rift basins. Notably, an inverse correlation exists between barite orebody thickness and underlying chert thickness: economic barite mineralization predominates where chert are 0–10m thick, while orebody thinning or pinch-out occurs where chert exceed 20m. Recent exploration breakthroughs at the concealed footwall of the Pingdi Fault (F1), where industrial?grade orebodies were first intersected, combined with the progress of peripheral survey, propose a prioritized exploration strategy: 1) priority targeting of the F1 footwall for large to super-large barite deposits, 2) systematic expansion of prospecting in known enrichment zones, and 3) innovative exploration leveraging spatial relationships between deposits. The F1 footwall exhibits exceptional potential, with high prospects for yielding breakthroughs in identifying large to super?large barite deposits.
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Study on rock formation and geological significance of late nearchaan biotite monzogranite in Liujiang region of eastern Hebei province
chen xiang zhi, Shi Qiang, shu run xiao, xu zhong yuan, li shi chao, chen kai yun
Abstract:
The neocarchean granite is widely developed in the Liujiang area of eastern Hebei, which is the key to solve the study of the formation and evolution of the early continental crust in the east of North China Craton, so it has been widely concerned by many scholars. This paper studies the geological, geochemical characteristics, zircon U-Pb dating and Sr-Nd isotope geochemistry of biotite monzogranite in Liujiang region, aiming to determine its origin and geotonic significance. LA-ICP-MS Zircon U-Pb dating with n(207Pb)/n(206Pb) intersection age is (2545±15) Ma, formed in the late Nearchean-early Paleoproterozoic; The geochemical analysis of the whole rock shows that it is quasi-aluminum-weak overaluminum, high potassium calcium-alkaline series potassium rock, Enrichment of large ion lithoophilin (LILE, for instance:Rb, Ba), Loss of high field strength element (HFSE, for instance:Nb, Ta, Ti), The right-leaning distribution pattern with light rare earth enrichment and heavy rare earth loss, The Eu abnormalities are not obvious; The(143Nd/144Nd)i value ranged from 0.509350 to 0.509384, Characteristics of a εNd(t) value of 0.3~0.9. Combined with the existing research results, it is believed that the biotite granite in this study has the typical geochemical characteristics of type I granite, which is the source of crust and mantle mixed magma, and is formed in the island arc environment after orogenic at the active continental edge arc-land collision.
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The first record of dinosaur eggs from the Xuancheng Basin of Anhui Province, China
Zhu Mengyuan, Mao Lei, He Qing, Li Shutong, Zhang Shukang, Dong Xuyang
Abstract:
Objectives: Dinosaur eggs in Anhui province are mainly preserved in Xiuning Basin and Qianshan Basin, and there are no records in Xuancheng Basin. Dinosaur eggs and eggshells from the Upper Cretaceous Xuannan Formation near Qingyijiangnan Avenue, Xuanzhou District, Xucheng city are the first records in Xuancheng Basin, which are important for the stratigraphic division and correlation of the K/T boundary. Dinosaur eggs in this paper were analyzed by macrostructural measurement and microstructural observation. Result: Results show that these eggs are long (the length is more than 100mm and width is 70mm). Chain or ridge form ornamentations are distributed on the outer surface and eggshell thicknesses varies between 1.10 mm and 1.80 mm. The boundary between the cone layer and the columnar layer is nearly straight, and the ratio between them is 1:4–1:3. The radial microstructures in the cone layer are arranged closely and pore are few with erect shape. Conclusions: These dinosaur eggs are belonged to Elongatoolithus andrewsi in Elongatoolithidae, which are the first detailed record in Anhui Province. These eggs are mainly preserved in the Upper Cretaceous Xuannan Formation. The studies of oospecies classification and future geochemistry provide important basic data for the dinosaur extinctions at the K/T boundary.
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A review of the mass extinction at the end-Permian
侯海海, Heqian, Liushujun, Gaolianfeng, Wangchongjing
Abstract:
The end-Permian mass extinction (EPME), as the largest extinction event in global geological history, resulted in the extinction of about 75% of terrestrial species and about 81% of marine species. Terrestrial vegetation, insects and terrestrial tetrapod vertebrates all experienced rapid and devastating impacts worldwide. The marine species that became extinct significantly included fusulus, trilobites, echinoderms and corals, and most of the species that became extinct or were replaced included brachiopods, bivalves, radiolaria, foraminifera and ammonites, etc. The extinction of EPME species was characterized by regional, selective and phased extinction. The eruption of the Siberian Igneous Province (SLIP) is highly coupled with the EPME time, and SLIP and its associated series of secondary events are considered to be the main driving force of EPME and the main factor of delayed biological recovery. The duration, intensity and regional distribution of some secondary events, such as ocean hypoxia and sea water warming, are still controversial, and a single secondary event cannot independently support EPME, which is the result of the comprehensive superposition of multiple factors. The SLIP outbreak promoted the release of a large amount of greenhouse gases buried in the sediments of inland basins and continental shelves into the atmosphere, and the rapid global warming led to the land crisis in advance. Extreme dry weather promoted the frequent forest wildfires and the collapse of terrestrial ecosystems. The intensification of continental weathering caused a large number of debris to be injected into the ocean, resulting in serious eutrophication, hypoxia of submarine organisms, ocean acidification and disturbance of Marine paleoproductivity, etc., resulting in the occurrence of Marine extinction events. However, the lag of terrestrial extinction led to the end of the terrestrial crisis later than the Marine extinction event. The global environmental catastrophe at the end of the Permian period had a huge impact on the Earth's ecosystem. By summarizing the process of the end-Permian mass extinction event and exploring the causes of the mass extinction, it is of great significance to understand the collapse of the PTB global ecosystem and predict the recurrence of similar geological events in the future.
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The response of volcanic ashes to magma recharge in aluminum-bearing rock series of Permian in Chongzuo area, western Guangxi
zhouhui, zhoupuhong, zhangqilian, zhangxiaoli, weifang, huangwenfang, huangguangqiong, lihuosong
Abstract:
Objectives: Studies on volcanic ash in aluminium-bearing rock series of Permian in western Guangxi were focused on its connection with mineralization, but there are hardly case about defining tectonic evolution and magmatic activity. In recent years, magma recharge has become a hot spot in the study of magmatic evolution, and abudant volcanic ashs in aluminium-bearing rock series in Chongzuo area is just an excellent window for observing magmatic activities.This paper attempts to further clarify the properties and eruption mechanism of volcanic ash in the Permian aluminium-bearing rock series. Methods: Line investigation, zircon geochronology, microscopic research and element analysis. Results: The volcanic ash of Permian aluminium-bearing rock series from Chongzuo area consists of detritus, crystal fragment, hyaloclastic fragment, volcanic dust. The detritus is mainly basaltic andesite, followed by basalt and a small amount of acidic rock, and composing a calc-alkaline series. The contents of Fe, Ti, Cr and V are high, among which the average value of Cr is 769.37×10-6, meanwhile the contents of rare earth are 121.9×10-6 ~ 433.0×10-6, with an average of 284.98×10-6, whereas δEu varies from 0.46 ~ 0.94, with an average of 0.78; It is rich in Th, U, Pb and LREE, but depletion in Nb, Ta, Sr and HREE. Fragment of cumulative crystal indicates the presence of magma reservoirs and the breakdown of the crystal mush. The andesitic volcanic ashes are mainly composed of antecrysts, few peritectic crystals and xenoliths, which reflect that magma recharge had been practised, and the content of inactive elements fluctuates greatly, and the variation range of Nb/Ta and Zr/Hf includes the chondrite - continental crust category, and the variation of δEu is large, indicating mixing of high differentiation and low differentiation magma. Conclusions: The volcanic ash has derived from the oceanic arc, and magma for recharge were mafic. Acknowledgements: This study was funded by “Educational project of science plan of Guangxi(No.2023ZJY1454)” and “Project of improvement research basic ability for young and middle-aged teachers in Guangxi Universities(No.2024KY1877) ” Key words: aluminum-bearing rock series; volcanic ash; cumulative crystal; basalt-andesite association; magma recharge; geochemistry; Chongzuo area.
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Complex Geomorphology-Fluvio-Tidal Interaction and Sedimentary Response in the Pinghu Formation of the Pingbei Area, Xihu Sag
YANG Pan, LI Lei, CHEN Zhongyun, LI Shuai, ZHANG Zhongpo, CHAI Yawei, Zhao Xing
Abstract:
Objective: Combining well-seismic data with sedimentary simulations can help clarify the coupling between subaqueous low-relief uplifts and fluvio-tidal interactions in the Pinghu Formation of Xihu Sag. Method: Utilizing well-seismic data, we initially explore the characteristics of complex topography and landforms, as well as tidal action features in the study area. By employing the sedimentary numerical simulation method (Delft3D), an idealized model is established to investigate the coupling relationship features between the subaqueous low uplift and tidal currents in the study area by altering topographic characteristics and tidal amplitude conditions. Results: (1) Influenced by the underwater low-relief topography, the sand bodies in the study area develop large-scale tidal sandbars and extensive sand sheets during the processes of flooding and ebbing tides.(2) Under specific geomorphic features, there is a positive correlation between tidal amplitude and the degree of delta modification, leading to the development of large-scale tidal sandbars, sand sheets, and tidal channels. Under the same tidal amplitude, the underwater low-relief topography forms larger-scale sandbars, sand sheets, and tidal channels compared to barrier island topography. Conclusion: The transformation and evolution of the delta in the study area can be divided into three stages: river-dominated stage, tidal reworking stage, and topography-river-tidal coupling control stage. The coupling effect of complex geomorphology and tidal currents in the study area on the modification of sand bodies is mainly manifested as tidal sandbars and extensive sand sheets on both sides of the tidal channels shaped by underwater low-relief topography. The interaction between this unique geomorphic feature and the fluvio-tidal hydrodynamic forces is significantly distinct from that of barrier island coastal systems, making it more favorable for the formation of large-scale lithologic traps.
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Discovery of the Sinemurian (early Jurassic) ammonite from Heyuan, Guangdong and its biostratigraphic significance
Lin Mu, Zhiqing Huang, Zhijun Wen, Qiang Wang, Yuyue Wen, Huayue Huang, Yanli Du, Fanwei Meng, Xiang He
Abstract:
Recently, we discovered the typical Corniceras-Paracononiceras ammonite fauna in the Early Jurassic strata around Wanlv Lake. As far as perspective of ammonite fauna is concerned, it can be compared with the Corniceras-Paracoroniceras assemblages in northern Guangdong, Hong Kong, Fujian, Northwestern Europe, and Alaska. The age is the Sinemurian of the Early Jurassic. Besides there were some other fossils including gastropods and spore-pollen. We will carry out more in-depth research in the future to reveal the paleoenvironment and paleoecological characteristics of the surrounding area of ??the Guangdong Heyuan in the Early Jurassic.
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Paleoenvironment and Organic Matter Enrichment Mechanisms of Zhanjin Marine Fine-Grained Sedimentary Rocks in the Central Qiangtang Basin
Li Lei, Wang Zhongwei, Wang Jian, Song Chunyan, Zhan Wangzhong, Li Wangpeng, Sui Boyu, Qi Jun
Abstract:
Objectives: In order to clarify the controlling factors of organic matter enrichment in fine-grained sedimentary rocks from the Lower Permian Zhanjin Formation in the central Qiangtang Basin. Methods: Forty fine-grained sedimentary rock samples were presented in this study to analyse the micropetrological characteristics, organic carbon content, elemental geochemistry, and mineralogy, and then explore the evolution of paleoenvironment and its control on organic matter enrichment. Results: The results indicate that the fine-grained sedimentary rocks can be classified into five lithofacies types based on their chemical composition, grain size and sedimentary structures, include the massive siliceous mudstone, massive siliceous silty mudstone, massive siliceous siltstone, laminated siliceous mudstone and laminated siliceous siltstone. However, the variation in organic carbon content is minimally influenced by its lithofacies changes. The patterns of geochemical indicators and variation of framboidal pyrite size suggest that above fine-grained sedimentary rocks were deposited in an oxic to dysoxic environment associated with significant influx of iron-rich and magnesium-rich terrigenous detritus, and minor hydrothermal activity. The influx of detrital nutrients not only promoted biological flourishing and increased the paleoproductivity levels of surface waters, but also enhanced the adsorption capacity for organic matter. Conclusions: This study concludes that the organic matter enrichment in these fine-grained sedimentary rocks is primarily controlled by paleoproductivity, clay mineral adsorption, and rapid sedimentation rates, the influence of redox conditions can be neglected.
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Construction and Preliminary Application of Geological Knowledge Database on Fault-fractured Outcrops
ZHANG Fangli, LIE Zijun, FENG Wenjie, LIU Hongping, LI Jieyu, LIU Yuangang
Abstract:
Fractures are a key factor in the formation of tight oil and gas reservoirs. The identification and description of fault bodies are of great significance for the exploration and development of tight-low permeability oil reservoirs. As the southern margin of the Ordos Basin has complex reservoir conditions and diverse enclosure type, the identification of fault bodies and fractures are the key to opening the oil reservoirs. However, due to the complex coexistence relationship between faults and fractures, the identification and description of fault bodies have long relied on the manual judgment and interpretation of geological experts. The geological interpretation results and knowledge lack effective organization and management, to some extent limiting the application level of geological knowledge of fault bodies. Therefore, this paper proposes a framework for building a geological object-oriented knowledge base. Based on structured organization of geological interpretation results of fault-fractured outcrops, data mining methods are involved to explore quantitative parameters for geological modeling. The application results show that the proposed framework can effectively realize the structured management and visual analysis of fault-fractured outcrops. It is expected to provide decision support for reservoir modeling and oil exploration.
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Recent progresses of seismic acquisition technology revealed in the two international conferences
Di Zhixin, Li Xuejiao, Chen Hao, Guo Yuke
Abstract:
There is a growing trend of petroleum exploration with a rising demand of oil and gas on the global scale, contributing a rapid development of geophysical exploration theory and technology. Understanding the updated progresses of petroleum exploration facilities and associated technics is essential for the oil exploration industry, supporting the national strategy of energy safety. In this paper, new seismic exploration facilities and technics presented on the European Association of Geoscientists and the Engineers (EAGE) Annual Conference and the International Meeting for Applied Geoscience & Energy (IMAGE) are summarized, aiming for reviewing the technical trend of the seismic exploration and acquisition in the past a few years. Seismic equipments evolved with intelligence and automation in general. Vibroseis, onshore node systems, and offshore node systems developed rapidly for broader receiving direction, wider band, higher density, and better resolution, while the designing of acquisition system in tectonically complicated regions is still challenging. The combination of technologies (such as Distributed Acoustic Sensing, DAS) and compressed sensing technology showed a potential for saving costs significantly in the future.
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Rock Mechanical Properties and Safety Drilling Recommendations of Paleogene and Paleo-Buried Hill Strata in Huizhou Depression
Bo Sun, Yuanfang Cheng, Zhongying Han, Junchao Yang, Zhuyu Zhao, Chuanliang Yan
Abstract:
The study of the mechanical properties of formation rocks is the basis for evaluating wellbore stability and ensuring safe drilling operations. To explore the mechanical properties of rocks in the Paleogene and Paleo-Buried Hill strata of the Huizhou Depression. This study conducted a comprehensive analysis of the mineral and clay content of the core rock samples taken from the formation, as well as mechanical properties experiments before and after immersion in the drilling fluid. The mechanical properties parameters and creep models of the rocks in the Paleogene and Paleo-Buried Hill strata were obtained. By analyzing the energy evolution characteristics, the elastic-plastic characteristics of rocks were quantified, and recommendations for safe drilling operations in formations were proposed. The research results show that the quartz, potassium feldspar, and clay content of the Enping Formation each account for about 30%, while the quartz content of the Wenchang Formation accounts for about 60%. The Buried Hill Weathering Zone contains almost no clay minerals, and the content of Inner Buried Hill is as high as 54.69%. The uniaxial compressive strength of the Paleogene and Paleo-Buried Hill strata is relatively low, generally ranging from 30.20 to 48.76 MPa. After soaking, the uniaxial compressive strength of the Enping Formation, Wenchang Formation, and Inner Buried Hill decreased by 27.55%, 26.82%, and 31.60%, respectively. The overall strength of the Buried Hill Weathering Zone is higher than that of other strata, with a larger internal friction angle and lower cohesion in the rock core. The creep curves of rock cores in various layers all exhibit attenuation creep characteristics, and the creep of the Buried Hill Weathering Zone is significantly smaller than that of other layers. The Paleogene and Inner Buried Hill strata should ensure a safe drilling cycle and should not be operated for long periods. The drilling fluid density should be appropriately increased, and reverse sliding hole operations should be carried out on time to prevent drilling tool blockage. This study will help to solve the problem of unclear understanding of the mechanical characteristics of the lower strata in the Huizhou Depression and contribute to the safe and efficient evaluation of regional strata and drilling work.
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U-Pb Geochronology, Geochemical Characteristics and Geological Significance of the Changning BIF Iron Depositin Eastern Hebei Province
Abstract:
Changning BIF is located on the northern edge of the eastern landmass of the North China Craton, at the southern end of the "Si-Ma-Chang" metallogenic belt in eastern Hebei. In the end of 2023, a total of 18 iron ore bodies have been delineated in the entire region, and an estimated resource of 565 million tons of iron ore has been explored. At present, there is almost no scientific research data on Changning iron ore reported in the media. This article conducted geochemical studies on biotite plagioclase granulite, potassic mixed granite, and magnetite amphibolite quartzite in Changning BIF. The iron minerals in the original rock were transformed and enriched during this event, ultimately forming a rich iron ore layer. The original rock recovery of biotite plagioclase granulite and potassium mixed granite indicates that the original rock of biotite plagioclase granulite may be neutral volcanic rock, while the original rock of potassium mixed granite may be granite or rhyolite.Elemental geochemical analysis indicates that the formation background of Changning BIF is closely related to island arcs and volcanic arcs. The rare earth distribution curve of the magnetite amphibolite quartzite rich in iron ore shows a slight left leaning shape, with obvious positive anomalies in La, Eu, and Y. The Y/Ho ratio is 32.67-48.18, with an average of 37.01, indicating that the iron ore in the Changning area inherits the characteristics of seawater and hydrothermal fluids, and its ore-forming material may come from a mixture of seafloor hydrothermal fluids and seawater. LA-ICPMS zircon U-Pb dating was performed on the surrounding biotite plagioclase granulite and potassic mixed granite interbedded in the ore body. The age of the upper intersection of 15 measuring points of the biotite plagioclase granulite is 2655 ± 44 Ma, which may represent the formation age of the biotite plagioclase granulite protolith; The intersection age of the 12 measuring points on the potassium mixed granite is 2516 ± 74 Ma, which may be a reflection of the early Cambrian tectonic metamorphic thermal event in the North China Craton.
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Discovery of Late Cretaceous compressional structures in northern Hainan Island?
YUN Xiaorui, FENG Jianyun, ZHENG Herong, ZHANG Ying, LUO Jun, ZENG Yan, LIAO Dawei, ZHANG Qiaoxun
Abstract:
Objectives: South China experienced multiple periods of extensional-compressional tectonic stress field reversals during the Late Mesozoic. The tectonic reversal from extension to compression between the Early Cretaceous to Late Cretaceous has been widely confirmed, but there is relatively little evidence of tectonic reversal during the Late Cretaceous. Hainan Island is located in the southern part of the South China Plate and is an overlapping area of the ancient Pacific tectonic domain and the ancient Tethys tectonic domain. It records complex tectonic-magmatic events and is a key area for studying the tectonic evolution of the continental margins of South China and the northern South China Sea. Methods: This study is based on the geothermal scientific exploration well FSR 1 deployed by Sinopec in the northern part of the Fushan Sag in the northern part of Hainan Island. For the first time, a set of granite interlayers between the Paleogene and Cretaceous was discovered in the northern part of Hainan Island, and systematic petrological, geochronological, and structural geological analyses were conducted on granite core samples. Results: The research results indicate that the granite interlayers in this set are mainly composed of plagioclase granite, diorite granite, and granodiorite, which undergo mineralization and alteration; The zircon U-Pb results range from 261 ~ 250 Ma, indicating that the crystallization age of this set of granite rocks is from the Middle-Permian to the Early-Triassic; Combining the sedimentary ages of the Changliu Formation of the Paleogene and the Baowan Formation of the Cretaceous, this study limits the emplacement time of the granite rock set to between the mid-late Late-Cretaceous and the Paleocene. Conclusions: Based on regional geological surveys, oil and gas drilling, geophysical data, and previous research results, this study identified a late Cretaceous NW-SE trending compressional structure in the northern part of Hainan Island, providing new evidence for the study of the Late Mesozoic extensional compressional structure transition in South China.
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The genesis and geological significance of basaltic trachyandesite in the Tiaojishan Formation of the Middle-Upper Jurassic in the Xuanhua area of northwest Hebei Province
Abstract:
Abstract:Previous studies on basaltic andesites are limited,and there is a lack of research on the characteristics of the lithospheric mantle of the North China Craton during the Middle-Late Jurassic transition.We conducted geological,petrological,and geochemical studies on the basaltic andesites of the Taijishan Formation in the Xuanhua District of Zhangjiakou City,on the northern edge of the North China Craton,to investigate their petrogenesis and mantle source region.The basaltic andesites have SiO2 content ranging from 48.73%to 53.23%,MgO content from 2.78%to 3.79%,TiO2 content from 1.65%to 1.93%,and Mg#values from 35 to 43,belonging to the alkaline basalt series.The Middle-Upper Jurassic Taijishan Formation basaltic andesites formed in the early Late Jurassic,underwent crystallization separation of clinopyroxene and plagioclase,as well as crustal contamination.They are formed by low-degree partial melting(1%to 5%)of the primitive mantle containing hornblende-garnet-pyroxenite-eclogite,influenced by the metasomatic action of the Pacific slab melt,with the metasomatic slab melt originating from the melting of oceanic plates younger than 25 Ma.The basaltic andesites represent the transformation of the lithospheric mantle on the northern edge of the North China Craton from a depleted mantle to a primitive mantle,primarily modified by the subduction of the ancient Pacific plate during the early Late Jurassic.
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Mineralogy, Geochemistry, and Geochronology of the Baishachong Composite Pluton and Skarn in the Gejiu Mining Area
daijiarun, Jiaoqianqian, Changhuacheng, Jiangxiaojun, Liwenchang, Zhupingping
Abstract:
The granite bodies associated with mineralization in the eastern Gejiu area are predominantly concealed, with the Baishachong composite granite body being one of the few that are exposed at the surface. Detailed field geological investigations have revealed that the northern part of this granite body consists of pink medium-to-coarse-grained potassium feldspar granite, while the southern part is composed of grayish-white medium-to-fine-grained biotite monzogranite. Moreover, skarn-type tin deposits develop at the contact zone with the surrounding rocks in the southern part. Consequently, it serves as an ideal object for exploring the relationship between magmatic activity and tin mineralization. This paper presents new geochronological, geochemical, and mineralogical studies on the granite of different lithologies and skarn-type ore bodies within the granite body. The crystallization age of the light pink granite is approximately 89 Ma, while the lower intercept age of the grayish-white granite is 80 Ma, and the age of the skarn cassiterite is 84 Ma. Additionally, although all the biotites in the Baishachong granite body are annite, the grayish-white granite exhibits more characteristics of regenerative biotite. Therefore, it is inferred that after the emplacement of the grayish-white granite body, magmatic-hydrothermal activity remained intense between 80 and 84 Ma, providing abundant ore-forming materials and fluids for the skarn tin mineralization. The garnets in Baishachong are mainly grossular-dominant grossular-andalusite solid solutions (And55.58~97.28Cro0.16~39.51(Ura+ Pyr+ Spe+ Alm)1.58~5.19), enriched in heavy rare earth elements (HREEs), depleted in light rare earth elements (LREEs), with negative Eu anomalies, and a significant positive correlation between Y and ΣREE, indicating their formation in the early stage of skarn development under relatively closed, low water/rock ratio, and weakly oxidizing neutral fluids. A positive correlation is observed between Al and Fe, as well as Ga and Fe in cassiterite, and the brightness variation of individual cassiterite grains is mainly related to Fe content, suggesting their formation in high-temperature magmatic-hydrothermal fluids with evident coupled substitution of Fe for Sn. Combined with garnet geochemistry, it demonstrates that the magmatic fluids forming the skarn are Fe-rich.
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Exploration progress of copper, nickel, cobalt and lithium in foreign over the past 20 years
CHEN Xifeng, SHI Junfa, TANG Jinrong, ZHANG Weibo, YANG Zhongxi
Abstract:
With the rapid development of the new energy vehicle industry, the consumption of four typical new energy minerals, including copper, nickel, cobalt and lithium, has led to the rapid growth. The demand of copper, nickel, cobalt and lithium will remain strong in the future. However, the contradiction between supply and demand of copper, nickel, cobalt and lithium is more prominent. With the increasingly intense competition among major countries, the geopolitical influence on new energy minerals are continuously enhanced. The study on the exploration progress of new energy minerals of foreign has important significance to deepening the basic geological research of new energy minerals, to optimize the layout of China's global new energy mineral industry chain, and is conducive to Chinese enterprises to carry out mining investment in foreign countries. Based on the study of the overall situation, distribution characteristics of new discovered important deposits and the exploration progress of main countries & regions, important deposits, the main deposits types & metallogenic belts of copper, nickel, cobalt and lithium in foreign in the past 20 years. The results show that① The net increases in reserves and resources of copper, nickel, cobalt and lithium of foreign in the past 20 years are more than 1 times, especially the lithium is more than 2 times, but the net increases are highly concentrated in a few countries.②Porphyry copper deposits, laterite nickel deposits, sandstone-shale-hosted copper (cobalt) deposits and brine type lithium deposits are the deposit types that contribute the most to the exploration progress of copper, nickel, cobalt and lithium respectively.③The Circum-Pacific copper-polymetallic metallogenic belt, Southeast Asian nickel metallogenic belt, Central African copper-cobalt metallogenic belt sand and South American lithium triangle lithium metallogenic belt are the metallogenic belts with the greatest contribution to the exploration progress of copper, nickel, cobalt and lithium, respectively. ④Large international mining companies have the most of the increases in reserves and resources of exploration progress of copper, nickel, cobalt and lithium in foreign in the past 20 years.⑤Some newly-emerging countries of new energy minerals are formed in the past 20 years. In the future, China should optimization the strategic layout of the whole industrial chain of overseas new energy mineral mining, and the emerging new mineral countries can be new fulcrums.
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Questionable usage of the Chinese name of the fossil plant genus Tingia
Abstract:
Tingia is a representative plant of the Late Paleozoic(Cathaysia Flora, widely distributed in East Asia. The genus was named by the Swedish paleobotanist T. G. Halle in honour of Dr. V. K. Ting, the founder of China"s geopaleontology. However, with time elapsing, the Chinese name of 齿叶 real intention of T. G. Halle, but also is not conducive to the promotion of the spirit of science and the spirit of scientists. This paper summarizes the research history of the genus Tingia, and suggests that the genus 丁氏属 or 丁氏蕨 should be adopted as the Chinese name of Tingia.
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Design and Implementation of an Online Paleogeographic Map Visualization System Based on GPlates and Vue
Abstract:
Paleogeographic maps are important spatiotemporal visualization tools for revealing geological processes such as surface evolution, plate tectonics, and species distribution, as well as for environmental resource studies and the construction of the Deep-time Digital Earth (DDE). Since the 1970s, international scholars have developed paleogeographic reconstruction models based on large volumes of geophysical data (mainly paleomagnetic data), geochronological data, and fossil data. After more than two decades of research, nearly 30 types of online paleogeographic maps have been published on platforms like EarthByte and the GPlates Web Portal, integrating information such as topography, geological maps, elevation data, magnetic anomalies, and lithology. In China, while many online geological information systems display data such as samples and fossils on modern maps, most systems lack the functionality for online paleogeographic map visualization. This limitation hinders the clear representation of geological data in spatiotemporal dimensions. This system aims to create a single-page web application (SPA) entirely based on open-source frameworks that enables rapid deployment of paleogeographic visualization. Users can switch between various paleogeographic reconstruction models and display geochemical and paleontological data points within a single page. The system adopts Vue components to achieve a clear separation of front-end modules from data, facilitating integration with Web GIS systems for data transmission and functional module consolidation. As a result, it can be quickly integrated into browser/server (B/S) architecture-based geological information systems.
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Geochronology of detrital zircons from metaclastic of Shishuyuan Formation in the North Qinling belt and its tectonic implication
ZHAI Wenjian, ZHAO Huan, YAO Shuai, PENG Yi, ZHAI Wenfang
Abstract:
The Shishuyuan Formation, located in the North Qinling Orogenic Belt, is a set of terrigenous clastic deep-water flysch deposits composed mainly of slightly metamorphosed sandstone and mudstone. LA-MC-ICPMS zircon U-Pb dating results show that the detrital zircon ages of the Shishuyuan Formation range from 438 to 3562 Ma, with a primary peak at ca. 949 Ma and five secondary peaks at ca. 2482 Ma, ca. 1707 Ma, ca. 1140 Ma, ca. 839 Ma and ca. 514 Ma. The youngest population of detrital zircon ages ranges from 438 to 543 Ma. Combined with the Devonian greenschist-facies metamorphism observed in the formation and the absence of ca. 414 Ma depositional records from the adjacent Kuanping Group to the north, the main depositional age of the Shishuyuan Formation is inferred to be the Middle-Late Silurian (438–415 Ma). Integrated regional studies suggest that the Shishuyuan Formation represents a tectonostratigraphic unit composed of sedimentary subunits of varying ages, which requires further subdivision into distinct units.Provenance analysis indicates that the sediments were primarily derived from the North Qinling Belt, with secondary contributions from the southern margin of the North China Block and the South Qinling Belt, characterized by a dual provenance. The tectonic setting of the Shishuyuan Formation and the Kuanping Group (Xiewan Formation) is inferred to represent a shared marine basin. However, unlike the late back-arc basin of the Erlangping Group, this basin is interpreted as a continental margin basin formed during Middle Silurian to Devonian post-collisional extension in the North Qinling Orogenic Belt.
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Selenium high background in the Kuanping Rock Group first discovered in Qinling area
XU Anmin, ZHENG Yanrong, WANG Donglin, HAO Di, WANG Hui
Abstract:
Selenium is one of the essential trace elements for the human body and plays a significant role in human health, Therefore, moderate intake and supplementation of selenium have become a lifestyle for pursuing health, and various selenium-enriched agricultural products are the main way for the human body to take in selenium. Selenium-rich soil and strata are the foundation for the development of the selenium-rich industry. In China, the distribution area of natural selenium-rich land resources is relatively small, and in some areas, the selenium output flux is greater than the input flux, making the sustainability weak. The Xi'an Center of Mineral Resources Survey of China Geological Survey first discovered that the Kuanping Rock Group has a high background of selenium. This discovery has expanded the development prospects of natural selenium-rich land resources in the Qinling area and has guiding significance for the development of selenium-rich characteristic land in the Qinling and surrounding areas.
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Extracting geological information and exploring vein-type fluorite mineralization in the Daxigou fluorite deposit in Inner Mongolia, China, using SPOT-5, Landsat-9 and ASTER Satellite imagery
Shen Jiale, Pei Qiuming, Zhang Li, Han Shuhe, Ma Shaobing, Chen Lei, Wang Shiming
Abstract:
Fluorite is a crucial mineral that has garnered substantial attention within the latest round of strategic undertakings for breakthrough mineral exploration at the national scale. Probing into effective approaches for extracting multi-source remote sensing data and predicting fluorite mineralization based on multifarious information holds paramount significance. This study employs the large-scale vein-type Daxigou fluorite deposit in the southern Great Xing’an Range of NE China as a case study. First, the geological structure was interpreted using SPOT-5 high-resolution images, and the stratigraphic lithology was effectively interpreted using the minimum noise separation method. Principal component analysis was employed to extract information regarding hydroxyl and iron alteration in the study area from Landsat-9 and ASTER remote sensing data. Similarly, silicon alteration information was extracted based on the numerical relationship between ASTER SiO? emissivity spectra and chemical composition. Through meticulous inspection and comparative analysis of alteration anomalies associated with known mineral deposits, it was ascertained that both hydroxyl and silicification alteration anomalies exhibit a pronounced correlation with fluorite mineralization. Furthermore, overlapping regions of these anomalies extracted from various remote sensing datasets demonstrate enhanced indicators of mineralization potential. Given that vein-type fluorite deposits are not selective for the surrounding rock and exhibit distinct structural, ore-controlling, and alteration development characteristics, a GIS platform was employed to simultaneously consider these two factors and superimpose the anomaly information extracted based on the three remote sensing data for comprehensive prediction. The results demonstrate that the delineated metallogenic prospecting area exhibits a high degree of consistency with the known mineralized zone, and two new prospecting target areas have been predicted in regions beyond the mining area. This study offers valuable guidance for subsequent peripheral prospecting in this area and has the potential to inform and advance the remote sensing prospecting prediction of vein-type fluorite deposits in other regions.
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Mineral association and implication of gold occurrence in Beiya gold mine, Yunnan Province
XU Nan, ZHOU Mengyan, XUE Boqiang, QIU Hangying, HE Xiang
Abstract:
Beiya gold mine is representative in Jinshajiang-Ailaoshan alkali-rich porphyry metallogenic belt. Many scientific studies have been carried out on the genesis, diagenetic ore-forming relations, ore-forming fluid properties and material sources. However, there is a lack of systematic mineralogical research. In this paper, we have studied mineral association and occurrence of gold minerals during gold mineralization. The results show that gold minerals are main of natural gold, followed by kustelite and electrum. The assemblage in gold mineralization is gold minerals + silver minerals + pyrite + chalcopyrite + galena + sphalerite + arsenopyrite + magnetite + siderite + covellite. Gold minerals are mainly fissured gold and encased gold, followed by inter-granular gold, and mainly occurring in pyrite, galena, chalcopyrite and other sulfides, as well as quartz, biotite and other gangue minerals, indicating that the ore-forming fluid is dominated by gold, iron, copper, lead, sulfur, silicon and other elements.
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Geological and geochemical characteristics and its geological significance of cobalt-manganese deposit in the Doushantuo Formation, Shiqian area, eastern Guizhou Province
Xu Hai, Zhou Xumei, Gao Junbo, Yang Ruidong, Yin Runsheng, Xu Jinghong, Xue Zhongxi, Xu Lili
Abstract:
Objectives: We investigate the cobalt-manganese (Co-Mn) deposits from the bottom of Doushantuo Formation in the Shiqian region, eastern Guizhou, to clarify the source, occurrence of Co and its metallogenic process. Methods: In order to systematically investigate the petrographic and mineralogical features and geochemical compositions of the Co-Mn ores, the author have combined with the SEM, major and trace element results of the rock (ore) samples. Results: The MnO and Co contents in Co-Mn ores range from 3.57 to 34.30% (average 11.01%) and 0.0131 to 0.0537% (average 0.0346%), respectively, with abnormal enrichment of multi-metallic elements (e.g., Ba, Ni, Cu, Zn). Original banded structures within ore-bed and altered Mn carbonate enclosed by Fe-Mn oxides, indicates the Co-Mn claystone originated from the supergene weathering of original Mn carbonates. The Mn-bearing minerals predominantly comprise Mn oxides (e.g., Hollandite, and Manganite etc.) and Co peaks are observable within Mn oxides, coupled a strong positive correlation between Mn and Co (R2= 0.8) indicates that Mn oxides are the principal carriers of Co. The elemental ratios, discriminant diagrams and rare earth element (REE) differentiation suggests Co-Mn mineralization originates from the hydrothermal activity. The positive Ce anomalies and the abnormal enrichment of trace metal elements (e.g., Ba, Co, Ni, Zn) of Co-Mn ores, coupled with the widespread development of coeval stromatolite dolomite, suggesting a diagenetic origin of the original Mn-bearing carbonates. Conclusions: The formation of Mn-bearing carbonates at the bottom of the Doushantuo Formation is closely linked to the late Neoproterozoic major geological events. The formation of rift basins caused by the breakup of Rodinia supercontinent and associated magmatic-hydrothermal activities may have provided mineralization space and sources for Co and Mn. Significant oceanic redox perturbations during the end of Marinoan glaciation triggered the precipitation of Mn oxides and subsequent transformed into Mn-bearing carbonate minerals via diagenesis. These Mn-bearing carbonates were ultimately formed Co-Mn claystones during the later surface weathering process.
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Late Cenozoic stress-induced fracture structure in Xiangshan orefield and its indication for uranium ore prospecting
Abstract:
Xiangshan uranium orefield in South China is a representative orefield of hydrothermal uranium deposit. The fracture structures are developed, which can be divided into stress-induced fracture structures and fluid-induced fracture structures (hydraulic fracture structures) according to the different sources of force. Fluid-induced fracture structures is the metallogenic structure of Xiangshan uranium orefield.In recent years, the author has made more discussions on the metallogenic structure of Xiangshan uranium orefield, but the combing and induction of the stress-induced fracture structure is relatively weak, the understanding needs to be deepened, and the significance of the location and prospecting of uranium deposits has not attracted enough attention.Through geological and geomorphological surveys, structural special surveys and AMT survey data analysis, a combing analysis of stress-induced fracture was conducted.The results showed that the main manifestations of stress-induced fracture structures were NE-direction, NW-direction and SN-direction faults, which were mostly distributed along the valley, and the tectonic rocks were loose and not completely cemented.The AMT surveys show a low-resistivity anomalous zone, closely related to warm and hot water, and is a product of late Cenozoic tectonic activity.The stress-induced fracture structures control the modern geomorphological structure pattern of Xiangshan, especially the NE-direction faults, which have a particularly profound influence, resulting in the stratiform-like volcanic intrusive complex of Xiangshan from southeast to northwest in a stepped subsidence, and buried in the deep part of the late Cretaceous red bed in the west, forming a component of the direct base of the red bed, indicating a good prospect for prospecting in the deep part of the red bed.
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Review and prospect of prefabrication methods for structural planes in engineering rock mass physical models
SU Zhandong, LI Kunze, SUN Jinzhong, LIU Xiaoli, LI Xiaorui, NIU Yao, ZENG Yangnong, LI Mengyuan, WANG Zhiwen
Abstract:
The structural plane of rock mass is an important factor controlling the stability of rock mass. In the process of rock mass engineering research, it is crucial to restore the natural rock mass structure and reflect the essential characteristics of in-situ rock mass. At present, indoor model experiments are one of the main methods for studying rock masses with structural planes, and the selection of prefabricated methods for structural planes in rock physical models test has a significant impact on the final results of the experiments. This article comprehensively summarizes the production methods of different types of structural planes in rock samples containing prefabricated structural planes from the perspective of engineering rock physics model experiments. The traditional methods for prefabricated structural surfaces mainly include cutting method, splitting method, thin strip drawing method, and pre embedding method. The first two are suitable for prefabricating structural planes on natural rock specimens, while the latter two are suitable for prefabricating structural planes on rock like materials. Specific methods are selected based on the different positions and shapes of prefabricated structural planes. At the same time, these methods are simple and easy to implement, and have been widely adopted by scholars. However, there are also certain problems, such as difficulty in controlling the opening degree of cracks and the accuracy of occurrence. The emerging 3D printing technology provides the possibility to solve these problems, which can be combined with various scanning techniques and has broad application prospects in rock mechanics physics model experiments. However, there is still a certain gap in mechanical properties between the 3D printed specimens and real rocks due to the limitations of the printed materials, and breakthroughs are still needed.
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Research on transient electromagnetic early secondary field signal extraction based on horizontal coplanar one-transmitter dual-receiving magnetic dipole device
WangJiaming, LiHaixia, LiuHuipeng
Abstract:
Objectives: To study the influence of magnetic dipole transient electromagnetic devices on the interference of the primary field during the detection process, to design the device and calculation method for extracting the early secondary field signal, and to carry out shallow exploration by using the early secondary field signal. Methods: Based on the conductive ring model, this study studied the interference effect of the primary field signal on the secondary field signal in the early stage by analyzing the influence of the primary field signal on the secondary field signal under different delay conditions. The variation law of the electromagnetic field intensity of the primary field received by the loop under different transmission and reception distances is also explored, and the conditions for the primary field to cancel out are analyzed. Results: Through simulation experiments, it is found that under the interference of the primary field, the earlier the time, the smaller the proportion of the secondary field signal in the total field signal, and the greater the difference between the total field and the secondary field response. Based on the theoretical calculation, the numerical condition of two sets of receiving coils to cancel the primary field is obtained, so that the primary field interference can be suppressed and the secondary field signal can be quickly extracted without changing the size of the original device. Conclusions: Compared with the traditional dipole device, the new device proposed in this study can effectively suppress the primary field signal, which makes the early secondary field anomaly caused by the target body prominent, which has significant advantages. In addition, through the detection experiment of underground pipelines, it is verified that the method proposed in this study can achieve ideal results in practical detection. The results of this study is of great significance for improving the anomaly recognition ability of shallow geological bodies.
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Characteristics and significance of high-density methane inclusions in Permian volcanic reservoirs in Jianyang area, Sichuan Basin
CHEN Junlang, LIU Xiaohong, TAN Chong, FENG Mingyou, GU Zhidong, YUAN Miao, LI Qiufen, ZHANG Chao, TANG Hongming
Abstract:
Objectives: High-density methane inclusions were first discovered in Permian volcanic reservoirs in the Jianyang area of the western Sichuan Basin, providing new evidence for the genetic identification of volcanic gas reservoirs. Methods: This study utilized Raman spectroscopy to determine the density of methane inclusions. Subsequently, the reflectance of asphalt vitrinite was computed based on the results obtained from asphalt Raman spectroscopy. Furthermore, experiments were carried out to investigate the homogenization temperature in brine inclusions coexisting with hydrocarbons. Moreover, PVTsim simulations were employed to estimate the paleo-pressure of gas reservoirs in the Jianyang area. Results: The methane inclusions have a Raman shift peak ranging from 2909.78 to 2912.47 cm-1 and a density of 0.21 to 0.34g/cm3, indicating their high-density characteristics. Furthermore, the reflectance of methane inclusions or pyrobitumen Raman vitrinite (RMVRo) ranges from 3.32% to 3.78%, indicating a high degree of thermal evolution. The methane inclusions also contain components such as C2H6, C3H8, CO2, and a significant amount of pyrobitumen distributed throughout the reservoir, suggesting a connection between the gas reservoir and the cracking of ancient oil reservoirs. The homogenization temperature of brine inclusions in hydrothermal minerals varies from 137 to 183°C, with an average of 165.8°C. PVT simulation results show that the capture pressure of brine inclusions associated with hydrocarbons in quartz and calcite within the gas reservoir ranges from 85.4 to 135.6 MPa, corresponding to a formation pressure coefficient of 1.9 to 2.3. Conclusions: Methane contains C2H6, C3H8, CO2 and other components, with a significant amount of pyrobitumen distributed in the reservoir. This suggests that the gas reservoir is related to the cracking of the ancient reservoir. The homogenization temperature of the brine inclusions associated with methane ranges from 115 to 135.6 MPa, with the corresponding formation pressure coefficient between 1.9 and 2.3, reflecting the abnormally high-pressure characteristics of the reservoir. The formation of high-density methane inclusions in volcanic gas reservoirs in the Jianyang area is linked to reservoir cracking caused by deep burial, and high-density pure methane inclusions serve as important evidence for the enrichment of cracking gas reservoirs. Furthermore, the integration of density, composition, and homogenization temperature of high-density methane inclusions can serve as indicator for evolution pathway of cracked gas reservoirs.
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Characteristics, Main Controlling Factors and Exploration Direction of Hydrocarbon Accumulation in Archean Metamorphic Buried Hill, Bohaiwan Basin
Zheng Dingye, Lin Huixi, Gao Xiaopeng, Yang Guili, Hao Yunqing, Xu Mei’e, Liang Shangzi
Abstract:
With the continuous discovery of large-scale integrated oil and gas fields such as BZ26-6 and BZ19-6, the metamorphic buried hills in the Archaeozoic era of the Bohaiwan Basin exhibit broad exploration prospects. Based on the dissection of typical oil and gas reservoirs as well as well logging and seismic data, this paper analyzes the distribution and development characteristics of oil and gas reservoirs in the metamorphic buried hills of the Archaeozoic era in the Bohaiwan Basin, classifies the types of oil and gas reservoirs, summarizes the key controlling factors for hydrocarbon accumulation, and points out the direction for further exploration. The results indicate that the distribution of oil and gas reservoirs is concentrated in the eastern part of the Bohaiwan basin and is significantly controlled by Cenozoic strike-slip faults. These reservoirs are characterized by deep burial, diverse lithologies, low porosity and permeability, normal to weak overpressure, and complex oil-water relationships. Based on the structure characteristics and source-hill relationship, oil and gas reservoirs are classified into two categories and four types: source-hill contact type, including source-side type dominated by lateral migration of oil and gas and source-underlying type dominated by downward and lateral migration of oil and gas; source-hill separation type, including source-external type dominated by unconformity transportation and source-upper type dominated by fault transportation. Among them, the low position source-underlying type and median position source-side type have greater exploration potential, followed by the high position source-external type and high position source-upper type. Extensive source-reservoir contact area, sufficient hydrocarbon driving force, good sealing capacity, and fault-controlled reticulate reservoirs are the four key factors controlling the hydrocarbon accumulation in the buried hills. In the future, emphasis should be placed on the source-underlying and source-side type buried hill structural belts within depressions such as the Jiyang, Bozhong, and Liaohe Depressions, as well as the adjacent concave-convex uplifts, and the internal structures of source-upper type and source-side type buried hills in steep fault zones such as the Jizhong and Huanghua Depressions.
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A study on the variability in the distribution of fracture networks in typical segments of ultra-deep strike-slip faults: A case study of the FⅠ17 fault in the Fuman area, Tarim Basin.
TAN Xiaolin, ZHANG Yintao, Lü Wenya, Xie Zhou, ZENG Lianb, YUAN Jingyi, XIONG Chang, SONG Yichen, LI Hao, ZHANG Kening
Abstract:
Objectives: The fracture networks controlled by strike-slip faults serves as the effective storage space and primary flow pathway for ultra-deep carbonate rocks in the Tarim Basin. Significant differences exist in the distribution characteristics of fracture networks in different typical segments. Methods: Using convolutional neural network-based methods, the FⅠ17 fault in the Fuman area is identified and divided into typical segments. The width of the fracture network development zone for each segment is quantitatively characterized through the FDI analysis. The distribution characteristics of fracture networks in the typical segments and their internal features are reflected through production capacity analysis of individual wells. Results: The FⅠ17 fault in the Fuman area can be classified into four types of segments: pull-apart stepover zone, push-up stepover zone, translation zone, and inflection-and-stepover zone, totaling 14 segments. Among these, the inflection-and-stepover zone can be further subdivided into push-up and pull-apart zone. There is a significant difference in the average width of the fracture network development zones in different typical segments. Under similar scales, the degree of fracture network development follows a distinct pattern: inflection-and-stepover zone > push-up stepover zone > pull-apart stepover zone > translation zone. Notably, the effectiveness of the fracture networks in the pull-apart stepover zone is stronger than that in the push-up stepover zone. The areas on both sides of the stepover zones and inflection-and-stepover zones, as well as the primary faults and the intersections between primary and secondary faults within the translation zones, are the dominant locations for the development of the fracture network. The central regions of the push-up stepover zones (or the push-up region in the inflection-and-stepover zones) exhibit a certain degree of fracture network development, whereas the central regions of the pull-apart stepover zones (or the pull-apart region in the inflection-and-stepover zones) show a comparatively weaker level of development. Conclusions: By integrating the analysis of the fracture network development zone widths for each segment with the production capacity analysis of individual wells, a heterogeneous development model for the fracture networks in typical segments of ultra-deep strike-slip faults was ultimately established.
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First seismic imaging practice of applying common-reflection-surface stack for improving seismic signal-noise-ratio of permafrost zone
LIURUIQI, LIUZHIWEI, WENXIAOGANG, KANGSHAOWEI, YANGDAYOU, LIUKUIXU, HOUDINGGEN
Abstract:
The Qiangtang Basin in Tibetan Plateau has been characteristic of near-surface permanent permafrost and high-steep Mesozoic strata, consequently which led to lower seismic signal-to-noise ratio (SNR) and complex wavefields and posed significant challenges for seismic imaging and structural interpretation. Based on the theory of Paraxial Ray breaking the assumption of horizontal layered model, common-reflection-surface (CRS) stack applied in seismic processing has the availability to high-SNR zero-offset profiles and obvious advantages in the permafrost zones. Using 2D seismic data from Qiangtang Basin, this paper first contrasts the CRS stack with CMP flexbinning, Prestack random noise attenuation (PreRNA) and Dip Moveout (DMO) as conventional seismic processing technologies for improving the SNR. The result showed that the prestack gathers derived from the CRS stack is optimal from the aspects of not only SNR and signal fidelity, but also the MVA quality control. The CRS zero-offset profile demonstrates more richer diffractions of middle and long apertures than by the DMO, PreRNA and flexbinning processing, good for future imaging the faults and strata breakouts. For improving seismic SNR of the permafrost zone, above comparison and applications present that the CRS stack availably used as one of key technologies applied in seismic processing, favorably achieving the depth-domain imaging of complex structures, and speeding up oil and gas exploration in Qiangtang.
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Discussion on green mine construction injecting green kinetic energy into high quality development of Hezhou City
Abstract:
Green mine construction, as an important measure to protect ecological civilization in the mining field and an important embodiment of the practice of "clear water and green mountains are gold and silver mountains", has been carried out in full swing in the whole country.Hezhou is rich in "stone" resources, with the largest white marble mineral deposits in central and southern China, with reserves of 2.6 billion cubic meters.In recent years, calcium carbonate and new-type prefabricated construction industry are the "two hundred billion yuan industry" created by Hezhou Municipal Party Committee and Government.The exploitation and utilization of mineral resources is the key issue form the development and growth of hezhou industry. How to maximize the exploitation and utilization of mineral resources and minimize the environmental damage is the urgent issue facing the current mineral exploitation.From the perspective of hezhou mineral resources and mining development status, promoting green mine construction is a new thinking of mineral resources management and mining development road under the new situation, and it is the only way to promote economic development and increase value.At the same time, it is the only way form Hezhou to optimize the industrial structure, scientific and reasonable layout, strengthen the leading industry, improve the industrial concentration and industrial level, and accelerate the pace of industrial development.
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Geochemical characteristics of the Qidushan granite in southern Jiangxi: Implications for REE Mineralization
ZHANG Ju, DING Feng, SUN Peijun, FAN Yuhang, WU Dehai, LI Yuan, REN Guogang
Abstract:
Objectives: Mesozoic granite in South China is an important original rock of ion-adsorption rare earth deposit, while Qidushan granite in Anyuan Country, Nanling, as the bedrock of Shitouping ion-adsorption rare earth deposit in southern Jiangxi, has obvious rare earth mineralization. Methods: In this study, the authors used geochemical and chronological data to explore the genesis and tectonic setting of these granites and their relationship with rare earth mineralization. Results: The results show that Qidushan biotite granite has high content of SiO2, K2O, Al2O3, Fe2O3, low content of CaO, TiO2, MgO, depletion of Eu, Sr, Ba, Ti, P and other elements, obvious negative Eu anomaly, total REE (ΣREE) is 196×10-6 ~ 464×10-6, LREE/HREE is 2.49 ~ 4.39, light REE is slightly enriched, zircon U-Pb age is 143.2 ± 1.8 Ma and 137.1 ± 2.4 Ma, respectively, and they are Mesozoic Early Cretaceous (late Yanshanian) granites with εHf(t) values ranging from-7.6 to-2.6, which belong to fractionated aluminous A-type granites. Conclusions: Comprehensive research shows that it is inferred that granite of Qidushan ,Shitouping, Anyuan Country, southern Jiangxi Province was formed in the extensional tectonic environment, in the crustal source area containing mantle components, which was formed by the subduction of paleopacific plate into the lower crust, plate rotation, crust thinning and asthenosphere upwelling, resulting in the mixing of crust and mantle-derived magma, which melted at high temperature to produce felsic magma, and then rose and emplaced to form Qidushan granite through separation and crystallization. The long-term extension of Mesozoic in southern China is conducive to the formation of highly differentiated granite in Qidushan, and the evolution of late granite to volatile-rich magma-hydrothermal system is of great significance to the formation of heavy rare earth ion adsorption deposits.
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Geochronology, geochemistry and geological significance of granite porphyry in Qibaoshan area, Wulian county, southern margin of Jiaolai Basin
Wang Xin, Zhan Honglei, Tang Mingying, Sun Lisha, Zhang Lei, Zhu Haibo, Hua Lei, Zhu Wei, Chen Jian, Li Shuangfei
Abstract:
The Jiaolai Basin is an important Au-Cu polymetallic metallogenic belt in eastern Shandong Province. The Qibaoshan subvolcanic complex in Wulian is a complex rock mass developed in the southern margin of Jiaolai Basin, which is most closely related to the metallogenesis of Au-Cu polymetals. With the development of prospecting work in the outer and deep parts of the complex, the granite porphyry has been discovered in the deep part of the complex. On the basis of lithographic observation and zircon U-Pb dating of granite porphyry, this paper attempts to clarify the genetic type, provenance characteristics and tectonic environment of this rock mass through whole rock geochemistry and zircon Hf isotope analysis. Zircon U-Pb dating results show that the granite porphyry was formed in 120.0±0.3Ma and 120.5±0.3Ma, which is early Cretaceous. The granite porphyry as a whole is characterized by high Si, Al, Na, and low Fe, Mg. It is a weak peraluminous rock with high potassium calcium alkalinity, relatively enriched in light rare earth elements and large ion lithophile elements, and deficient in heavy rare earth elements and high field strength elements, with obvious Ta, Nb, Sr and Eu negative anomalies, belonging to type I granite.The Hf isotopic composition of the zircon is obviously negative, and the mean age of the two-stage model is 2891Ma, indicating that the magma originates from the Mesoarchaean ancient shell source material. Tectonic environment discrimination shows that the granite porphyry was formed in the post-orogenic tectonic environment after the plate subduction briefly extended, belongs to post-collision granite, and is basically consistent with the subduction of the Pacific plate to Eurasia and the magmatism related to mineralization in the region.
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Investigation and Evaluation of Thorium and Related Research Progress in China
Meng Yanning, Fan Honghai, Chen Jinyong, Zhong Jun, Cai Yuqi
Abstract:
Thorium is another nuclear fuel other than uranium, and thorium-based molten salt reactors are one of the reactor types of the fourth generation of nuclear power technology. In recent years, breakthroughs in the development and application of thorium resources have brought development opportunities and challenges to the investigation and evaluation of thorium resources. This paper summarizes the current research progress of thorium resources in China"s investigation and evaluation, potential prediction and metallogenic theory: it divides the thorium metallogenic belts and thorium genesis types in China, and constructs the metallogenic models of typical deposits in different genetic type, which lays a foundation for the research of the basic theory of thorium resources. The investigation and evaluation method of thorium resources and the prediction technology of digital telescope were established, which provided technical support for the potential evaluation of the thorium resources in China. The metallogenic mechanism of thorium was analyzed. It looks forward to the development prospect of available types of thorium resources in China, and analyzes the problems existing in the investigation and evaluation work of thorium resources. It provides a reference for the future deployment of thorium resource exploration and development.
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LA-ICP-MS U-Pb age of zircons from basaltic andesite in the Nanbaishuihe Formation, Jixian System, in western part of Central Qilian Block and its geological significance
mayouwen, liuchangyun, zhangjinming, chenguangting, caihangjia
Abstract:
The Nanbaishuihe Formation of the Jixian System is a basement series in the western part of the Central Qilian Block, which is of great significance to the study of Proterozoic geological structure evolution of the Central Qilian Block. The author discovered basaltic andesite interlayer in Nanbaishuihe Formation through 1: 50,000 regional survey, Zircon U-Pb chronology and petrogeochemistry of the basaltic andesite have been studied in this paper. The dating results show that the formation age of basaltic andesite is 1489±16 Ma, which belongs to the Changcheng Period of Mesoproterozoic, and the successor zircon age is 1926 ~ 2053 Ma, which is the geological record of the Columbia supercontinent convergence event. The geochemical analysis of the rocks shows that the geochemistry of the rocks is rich in Na2O, FeOT, Al2O3 and poor in TiO2 and K2O. The rare earth partition curve is right-leaning light rare earth enrichment type, LREE/HREE=3.73~6.72. (La/Yb)N is 5.66~7.56,δEu= 0.69~0.81, and large ionic lithophile elements such as Ba, Th, U, and Nb are enriched, while Nb, K, P and Ti are relatively depleted, which has the characteristics of alkaline basalt in the plate and is the product of stretching mechanism. It is a response to the breakup event of the Columbia supercontinent in the early Middle Proterozoic of the Qilian Block.
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High heat production granites and its metallogenic effects
Abstract:
As potential geothermal resources, high heat production (HHP) granites have attracted attention from countries around the world. However, the genetic links between HHP granites and hydrothermal metal deposits have not received the corresponding emphasis and reviews.
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Determination and geological significance of A-type granite from Wangzhoushan caldera in southeastern Zhejiang
ZHANG Zhi), Chu Pingli), ZHAO Kai), He Zhenyu), XU Xi-sheng)
Abstract:
The Wangzhoushan caldera is located in Cangnan County, southern Zhejiang Province, and the main eruption products are Late Cretaceous rhyolites and rhyolitic pyroclastic rocks. The central intrusive in the caldera is the typical alkaline granite, containing typical alkaline ferromagnesian minerals arfvedsonite and aegirine with micrographic texture and miarolitic structure. LA-ICP-MS zircon U-Pb dating results show that the formation ages of alkaline granite are 91.3±1.1~90.4±0.8 Ma. The alkaline granites have high SiO2 contents (76.9%~77.9%), and alkalis contents (Na2O+K2O=7.80%~8.51%), and low CaO, MgO, Al2O3. They are rich in large ionic lithophile elements (LILE; e.g., K, Rb, Th, U) and high field strength elements (HFSE; e.g., Nb, Ta, Zr, Hf), poor in Ba, Sr, P, Ti, and show high (Ga/Al) × 104 ratios (3.82~4.28) and high zircon saturation temperature (798~889 ℃). Different samples of the Wangzhoushan alkaline granite have similar whole-rock Nd isotopic compositions (εNd(t)= -4.2~-3.8) and zircon Hf isotopic compositions (εHf(t)= -6.4~-1.7), indicating that the Wangzhoushan alkaline granite may be mainly derived by partial melting of crustal materials with minor contributions from mantle-derived components. The Wangzhoushan alkaline granite belongs to the typical peralkaline A-type granite, which is another example found in the Late Mesozoic A-type granite belt in the coastal areas of Zhejiang and Fujian Provinces. The magma origin of the Wangzhoushan alkaline granite and the contemporaneous coastal alkaline granite (101~86 Ma) in Zhejiang-Fujian is controlled by the subduction and rollback of the paleo-Pacific plate in the Late Cretaceous. Under the strong extensional tectonic setting, the depleted mantle-derived magma upwelled, resulting in the partial melting of the middle and lower crustal materials, and the magma of the high-silica peralkaline A-type granite was formed by the magma mixing and fractional crystallization processes.
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Content, Impact, and Response Strategies of the U.S. Critical Minerals Consistency Act
niuyingchao, gaoxuezheng, qifanyu, zhangchao, shangyuntao, lixiaolei
Abstract:
This paper examines the recently enacted Critical Minerals Consistency Act in the United States, arguing that its purpose is to bolster the U.S.'s dominant position in the global supply chain of critical minerals and reduce dependence on imports of such minerals from foreign countries, particularly China. This will have profound implications for the security of China's critical minerals supply chain. Therefore, this paper proposes that the Act will lead to significant changes in the competitive landscape of the Chinese market, posing enormous challenges to the stability of supply chains, the green transformation and upgrading of the mining industry, and the demand for technological innovation. Based on this analysis, the paper suggests that China should strengthen the foundation of domestic critical mineral resources, timely assess and adjust the list of strategic minerals, closely monitor new trends in global supply chain adjustments, and expand diversified and autonomous mining markets as strategies to address risks in the critical minerals supply chain.
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Genesis and indication of mineralization of pisolites (ooids) in sedimentary bauxite deposits from Western Guangxi
LUO Jingwei, XU Haipeng, PANG Baocheng, XU Jianqi, XIANG Shaoli, LU Guanghui, Yao Shuangqiu
Abstract:
Pisolitic-oolitic-type bauxite is one of the main types of sedimentary bauxite. Pisolites (ooids) are mainly composed of aluminum-containing minerals such as diaspore and clay minerals, which are closely related to aluminum mineralization. However, the formation mechanism of pisolite (ooid) is not yet clear. This research conducted mineral petrographic and geochemical characteristics on the pisolite (ooid) from Western Guangxi, analyzing the morphological characteristics and elemental composition of diaspore in pisolitic (oolitic) bauxite, and exploring the genesis of pisolite (ooid) and metallogenic mechanism of bauxite. The observation results of petrology show significant differences in the morphology and distribution characteristics of diaspores in the ooids of sedimentary bauxite from Western Guangxi. Based on these differences, the ooids can be divided into six types. The results of the SEM-EDS and EPMA analysis showed that Fe, Si, Ti, and other elements generally existed in the diaspore. Anatase is closely associated with diaspore. There were no signs of metamorphism in the roof and bottom wall-rock limestone of ore-bearing bauxite ore in Western Guangxi, which indicated that the genesis of the diaspore was simple crystalline. The morphological characteristics and chemical composition of the diaspore at the ooid core→ ooid circle layer → ore matrix are different, as well as the lithological features such as a large number of broken pisolites (ooids), directional arrangement of ooids and clastics, dry shrinkage cracks and plastic deformation of ooids. These indicate that the ooids in sedimentary bauxite in Western Guangxi are of colloidal origin and have undergone mechanical transformation. The formation of ooids in Western Guangxi went through four stages: material preparation, hydrolysis of clay minerals, formation of ooid core, and formation of ooid circle layer. It is formed by the weathering of aluminosilicate material to form clay minerals, which further hydrolysis of clay minerals condenses and precipitates to form ooids. The Si-Al ratios (SiO2/Al2O3; 0.02~0.35), ore Chemical Index of Alteration (CIA; 94.41~99.96), Index of Compositional Variability (ICV; 0.07~0.74) analysis results show that the pisolitic (oolitic) bauxite has undergone intense chemical weathering and is the product of intense weathering leaching. The formation of sedimentary bauxite in Western Guangxi is related to leaching and colloid processes, and the bauxite has undergone different degrees of transformation after formation.
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Sedimentary characteristics and constitutive pattern of the Deltaic Sand Body of the Shan 2 Member - He 8 Member in the southeastern Ordos Basin
Wang Yiling, ZHANG ChengGong, HU JianLing, DU JiaNing, HOU LinJun, CHEN HongDe
Abstract:
[Objectives] The exploration and development of the Ordos Basin have progressed rapidly. With the deepening exploration of effective reservoir identification technology and the continuous advancement of quantitative characterization research, the southeastern part of the basin has demonstrated enormous exploration potential. Strengthening the understanding of sedimentary evolution in this region, clarifying the sedimentary sand body patterns in the southeastern part of the Ordos Basin, and analyzing their spatial combinations are of significant importance for the exploration and development of tight gas in the basin. [Methods] Sedimentary characteristics in the study area were analyzed using methods such as petrographic observation, grain size analysis, and geochemical analysis. By identifying the configuration elements of the study area and combining well log data, a regression analysis was conducted to establish a discriminant formula for the configuration elements, enabling the qualitative and quantitative identification of configuration elements and constructing the three-dimensional distribution characteristics of configuration elements in the study area. [Results] In the study area, 9 major lithological types and 10 configuration elements were identified in the Shan 2 Member to He 8 Member. Fisher's discriminant formula for five configuration elements—submarine distributary channels, submarine distributary bay, mouth bars, sheet sand, and peat marshes—was established. Six stacking modes were identified: submarine distributary channel – submarine distributary channel, sheet sand – sheet sand, submarine distributary channel – sheet sand, distributary channel – distributary channel, mouth bar – mouth bar, submarine distributary channel – mouth bar. [Conclusions] In the study area, the Shan 2 and Shan 1 Member developed meandering river delta front subfacies, and He 8 Member developed braided river delta front subfacies and delta plain subfacies. Based on the discriminant formula for configuration elements, sand body configuration distribution models in the Shan 2 Member, Shan 1 Member, and He 8 Member were established. The sand body configuration in the Shan 2 Member is mainly developed in submarine distributary channels, while the Shan 1 Member is dominated by submarine distributary channels and sheet sand, with frequent overlap between them. The He 8 Member is dominated by submarine distributary channels, mouth bars, and sheet sand, with a rich variety of sand body stacking patterns.
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New Progress in Silicon (Si) Isotope Geochemistry and GeneticMechanism of Siliceous Rocks
Zheng Kaihang, Li Xi, Zhu Guangyou, Gao Heting, Li Sheng, Zhang Jiezhi, Chen Hongzhou, Liu Jianyong
Abstract:
The accurate identification of the genetic mechanism of siliceous rocks (SiO2) has always been a challenging issue in geological research. As the direct tracer isotope of siliceous rocks, silicon (Si) isotope holds great potential in revealing the genetic mechanism of siliceous rocks. In recent years, with the rapid development of high-precision Si isotope testing and analysis techniques, significant progress has been made in tracing the silicon sources, migration processes, and sedimentation-diagenesis evolution backgrounds of different siliceous rocks using Si isotope. To further promote the broader application of Si isotope in constraining the genetic mechanism of siliceous rocks, this paper reviews the genetic types of siliceous rocks, the analytical testing methods of Si isotope, the fractionation mechanisms, and its applications in the study of siliceous rock genesis, and reaches the following understandings: Siliceous rocks can be classified into hydrothermal genesis, volcanic genesis, biogenic genesis, and metasomatic genesis based on their genetic types. Both multi-receiver inductively coupled plasma mass spectrometry and secondary ion mass spectrometry have high precision in Si isotope testing, reaching accuracies of better than ±0.10‰ and ±0.10‰ - ±0.22‰, respectively. The fractionation mechanism of Si isotope involves multiple aspects. Diffusion causes the selective migration of Si isotopes and influences the degree of isotopic fractionation. Factors such as temperature, pressure, and chemical composition interact during the crystallization process, determining the degree of Si isotope fractionation. Evaporation affects the fractionation of Si isotopes by altering the chemical composition and physical properties of the melt. In low-temperature geological processes, Si isotope fractionation is more significant than in high-temperature geological processes, such as chemical weathering, biogenic-abiotic precipitation, biological absorption, and adsorption. Organisms absorb silicon during the process, causing isotopic fractionation and resulting in changes in the relative abundance of silicon isotopes in biogeochemical processes. There are differences in Si isotope fractionation among different organisms during the absorption process. The application of Si isotope in the study of siliceous rock genesis demonstrates its unique advantages, such as revealing the hydrothermal activity characteristics of hydrothermal siliceous rocks, the magmatic origin and evolution of volcanic siliceous rocks, the formation mechanism of biogenic siliceous rocks, and the silicon sources of metasomatic siliceous rocks. To more accurately identify the genetic mechanism of siliceous rocks, future research needs to conduct in-depth explorations in improving the analytical testing precision of Si isotope, accumulating large sample data, clarifying the fractionation mechanism, and constructing genetic theoretical models. This paper showcases the unique advantages and significance of Si isotope in the study of siliceous rock genesis, providing a useful reference for future research directions and application fields.
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Circulation and Evolution of Surface Water and Groundwater along the Yellow River in Western Shandong Province
zhaoyaru, kangfengxin, xihongfeng, lijialong, qinpeng, suihaibo, zhengtingting, yanghaitao
Abstract:
Objectives:In order to clarify the influence zone of seepage recharge pore water in the Yellow River and Dongping Lake, and to clarify the evolution law of surface water groundwater circulation along the Yellow River in western Shandong Province. Methods:Groundwater chemistry and isotope techniques were employed to identify the sources and controlling factors of the main hydrochemical components in groundwater and determine the recharge scope. The groundwater dynamics approach and end-element mixed model were utilized to quantitatively calculate the seepage of the Yellow River and Dongping Lake water and the transformation among different water bodies. In combination with the results of groundwater dynamics and hydrochemical isotopes, the evolution rule of surface water-groundwater circulation along the Yellow River in western Shandong Province was probed. Results:The research shows that the main hydrochemical types are HCO3-Ca ?Mg type, followed by HCO3-Ca and HCO3?SO4-Ca type, and the hydrochemical components are controlled by the weathering and dissolution of silicate rocks. Through the application of groundwater dynamic field, hydrochemistry and isotope methods, the influence zones of water seepage and recharge of the Yellow River and Dongping Lake are calculated to be 1.5~4.5 km and 0.5~1.5 km respectively. During the wet season (2023.6 ~2023.9), the water leakage of the Yellow River and Dongping Lake was 4.5763 million m3 and 2.2280 million m3 respectively. During the low water period (2023.10~2024.5), it is 2.6150 million m3 and 4.5691 million m3 respectively. Conclusions:The groundwater in the study area is mainly replenished by atmospheric precipitation, and the water level of the Yellow River is higher than the ground on both sides, with leakage replenishing the Quaternary pore water on both sides. The surrounding terrain of Dongping Lake is high in the northeast and low in the southwest, and the lake water permeates the surrounding Quaternary pore water. The pore water receives atmospheric precipitation and water from the Yellow River and Dongping Lake, and then permeates and recharges the underlying karst water. The research results of groundwater - surface water cycle evolution can provide a reference for the calculation of groundwater resources in this area.
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Quaternary sedimentary environment in the source area of the Yixi River and Development Process of the river Implications, Fujian Province
Zhao Juxing, Zhang Shuguang, Lin Shuzhen, Ye Jun, Zhang Peng, Li Chang''an
Abstract:
Objectives: The Yixi River is a primary tributary of the Shaxi River, which is upper tributary of the Minjing River, valley geomorphology of the Yixi River is more representative in Fujian Province. Methods: In this study, we completed a Quaternary core (GC4) with Quaternary 22.4m in the source area of the Yixi River, analyzed sedimentary environment according to AMS14C, Grain-size and magnetic susceptibility. Discussed sedimentary environment in the source area of the Yixi River and development process of the river implications by comparison of regional lithostratigraphy and characteristic of valley geomorphology. Results: GC4 was divided to 5 sedimentary stages from middle of Late Pleistocene till now: fluvial facies, limnetic facies, weathering lacustrine facies, pluvial facies and fluvial facies. Sedimentary discontinuity happened in later Late Pleistocene. Conclusions: Sedimentary environment in the source area reflected regional neotectonic movements were as follows: uplift, sinking, steady, uplift rapidly, sinking first and then sinking, uplift durably, corresponding valley geomorphology consisted in in the source area, upper and middle of the Yixi River. The river appeared in middle of Late Pleistocene, valley geomorphology completely developed in middle of Holocene. The most rapidly uplift occurred in later Late Pleistocene. Keywords: source area; sedimentary environment; Grain-size; magnetic susceptibility; valley geomorphology
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Petrogenesis and metallogenic significance of two-mica granites from the Qiongrang, SW Muji, NE Pamir
qianxukun, liuxiaoqiang, mahuadong, xiaili·aerken, songzhihao
Abstract:
The Triassic granites in the West Kunlun-Pamir region is intricately linked to the evolution of the ancient Paleo-Tethys and metallogenesis of rare metals. We conducted a comprehensive study of the petrology, zircon U-Pb geochronology, major and trace element geochemistry, and zircon Hf isotopic analysis of two-mica granites from the Qiongrang, SW Muji, NE Pamir. Zircon U-Pb dating yield the age of around 211.6 Ma, suggesting two-mica granites from the Qiongrang emplaced at Late Triassic. The two-mica granites from the Qiongrang exhibit high levels of SiO2 (73.24% ~ 74.09%), Al2O3 (14.50% ~ 15.01%), and K2O (5.52% ~ 5.75%), and low TiO2 (0.15% ~ 0.18%) and MgO (0.30% ~ 0.37%). They also exhibit strongly peraluminous geochemical features (A/CNK = 1.12 ~ 1.15). The studied rocks are rich in Rb, Th, U, K and LREE, depleted in Sr, Ba, Nb, Ta, Ti, P and HREE, with obviously fractionation of LREE and HREE ((La/Yb)N = 44.62 ~ 54.58) and negative Eu anomaly (Eu/Eu* = 0.52 ~ 0.59), belonging to strongly differentiated S-granite, formed by the dehydration melting of mica from metamudstone sources. The zircon εHf(t) value of two-mica granites from the Qiongrang from -7.93 to -0.91, and the zircon εHf(t) value of the Dahongliutan granites range from -8.8 to -1.4. The two-mica granites from the Qiongrang contain relatively high levels of Li and Be, and they are closely related in time-space to the Dahongliutan rare metal pegmative veins, it is speculated that two-mica granites from the Qiongrang possess significant potential for the exploration of hard-rock lithium-beryllium mineralization.
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Discussion on the genesis of Pleistocene deep pore brine of sand-gravel type in the Mahai area, northern margin of Qaidam basin
Chen Jingyuan, Wang Qingchuan, Chen Jinniu, Song Guichun, Zhang Mingzhu, Lu Liang
Abstract:
Objectives: To discuss the hydrochemical characteristics and the genesis of gravel-type deep brine of the Mahai area in the northern margin of Qaidam Basin. Methods: The hydrochemical and H-O, S, Li isotopic characteristics of the Pleistocene deep brine were analyzed. Results: The results show: ①The hydrochemical type of brines are chloride-type. The K+ and Na+ of the content element are high, and the majority are higher than comprehensive evaluation index with a good resources potential; ② The ion characteristic coefficients and isotopic composition of brine indicate the brine has the characteristics of salt rock dissolution, clay mineral adsorption, strong evaporative concentration, and relatively closed conditions . Conclusions: The brine is the product of a series of geological processes such as water-rock reactions, leaching, adsorption, and evaporation concentration by atmospheric precipitation. In the transition zone between the terminal salt lake and the alluvial fan, with the increasing pressure of overlying formation, the residual ancient water was moved to the sand-gravel layers with low pressure in front of the mountains, and eventually infiltrates to the deep sand-gravel layers, then formed the gravel-type deep pore brine deposit under the condition of relative sealing.
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Naafs BD, Castro JM, De Gea GA, Quijano ML, Schmidt DN, Pancost RD. 2016. Gradual and sustained carbon dioxide release during Aptian Oceanic Anoxic Event 1a. Nature Geoscience, 9(2): 135-139.Yi Haisheng1), Yi Fan2), Tian Kangzhi1), SHI Yuxiang3)
Yi Haisheng, Yi Fan, Tian Kangzhi, Shi Yuxiang
Abstract:
The wet and dry changes in paleoclimate is an important research content in study and reconstruction of paleoenvironments during geological history, while the paleo-precipitation is an important indicator of wet and dry zonation of the land surface climate. According to global and Chinese modern plant leaf carbon isotopes(δ13Cleaf) data, it is believed that the δ13Cleaf values of the C3 plant are controlled by the magnitude of precipitation, with positive δ13Cleaf in arid zones and negative δ13Cleaf in humid zones, and it is straightforward to calculate mean annual precipitation (MAP) by using logarithmic equations of δ13Cleaf versus MAP. Previous studies shows that the nC27, nC29, and nC31 spectral peaks in the saturated hydrocarbon chromatograms are typical markers for the identification of organic matter from terrestrial plants sources in sedimentary strata, and the δ13C of these n-alkanes(δ13Cn-alkanes) records the carbon isotopic signals of the leaf of the plants(δ13Cplant), therefor it is possible to calculate and reconstruct the terrestrial plant leaf carbon isotopes(δ13Cleaf) after calibrating the effect of pedogenesis and diagenetic. Finally, based on the isotopic fractional coefficient (Δ‰=δ13CCO2 -δ13Cplanr) between paleo-atmospheric CO2 (δ13CCO2) and the plant (13Cplant), and by using the fitting equations of Δ‰ values to MAP (mm/yr) which was established in this paper, we quantitatively calculated the paleo-precipitation and delineated the dry/wet changes of the paleoclimate during the deposition process of the section, and we also discuss the influence of latitude, altitude, and temperature on the reconstruction results. The Cenozoic climate in China has undergone significant changes, which was manifested by the climate was controlled by the planetary wind system in Paleogene, while it evolved into a monsoon climate in Neogene. In this paper, we reconstructs the variation curves of paleo-precipitation correspond to the succession from Eocene upper member of Xiaganchaigou Formation to the Quaternary Qigequan Formation of the Fengxi 104 wells (4514m ~530m ) in the Qaidam Basin. The result showed that during the deposition of the Oligocene Shangganchaigou Formation, the Qaidam Basin receivedStheSleastSamountSofSprecipitation of only 250 mm/yr, while during the deposition of Pliocene Shizigou Formation, the Qaidam Basin receivedSthe maximum precipitation which is up to 1200 mm/yr, thus we proposed that the increase of precipitation in 8Ma may be related to the emergence of the Asian monsoon and the climate humidification in China.
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Distribution characteristics and risks of heavy metal pollution in sediments of Dongting Lake and its tributaries and impact factor analysis
Chen fangwei, Li Cong, guojun, zhangchengan, maoxiong, tanghengjia, liaoqi, chenchuang
Abstract:
[Objective] To Studying the distribution characteristics, risks and driving force of heavy metal pollution in the sediments of Dongting Lake and its tributaries can provide a scientific scheme for the treatment of heavy metal pollution in the surface sediments of the basin, and play a vital role in ensuring the ecological security of the basin.[Research Methods] This paper comprehensively evaluates and analyzes the content of 7 kinds of heavy metals in Dongting Lake basin, combined with different distribution characteristics of the basin. Introduce geographic detector model for spatial differentiation of surface sediments, combined with the ls and geographical weighted regression model, quantitative explore all kinds of influence factors on the geographical space of the lake surface sediments of heavy metal pollution distribution driver, while the Arcgis of the main influence factor correlation coefficient of spatial visual expression.[Results] The results show that: (1) the Igeo (ground accumulation index) of the mean of Cr, Cu, Mn, Ni, Pb and Zn elements in Dongting Lake sediment is less than 1, which is to the mean of Cd Igeo is between 1 and 2, which belongs to moderate pollution.(2) through the geographic detector model, rainfall, distance from the highway, DEM, sand and clay to the dongting lake sediment heavy metal accumulation index (Igeo) has strong interpretation, shows that dongting lake sediment heavy metal pollution by geographical factors such as influence, but also closely related to human activities.[Conclusion] 1. On the whole, the average value of the sediments in Dongting Lake area is 2, which belongs to the medium pollution degree.2. The serious pollution areas are mainly concentrated in the Zijiang River basin and the Xiangjiang River into the Dongting Lake basin and the center of Dongting Lake, and the sediment sediment in the Yuanjiang River basin shows moderate pollution.3, through the geographical detector, select rainfall, according to the highway distance, DEM of sediment heavy metals Itot spatial distribution interpretation of strong factors, interaction detector results show that the factor interaction are nonlinear enhancement, shows that the selection of environment, natural factors on the lake surface sediment heavy metal spatial distribution dispersion play a driving role.
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Characteristics of fluid inclusions and classification of accumulation period in Permian volcanic reservoirs in western Sichuan Basin.
shi zheng, shi huiju, WANG Yelei, XIA Peng, xiang siyuan
Abstract:
In order to determine the hydrocarbon accumulation period of Permian volcanic reservoirs in western Sichuan basin, petrographic analysis of fluid inclusions, fluorescence microanalysis, homogenization temperature measurement were conducted to solve this problem.The results show that the main host minerals of the inclusions are quartz and calcite filled in the pores, and the inclusions are distributed in bands or groups. The hydrocarbon inclusions are relatively mature and appear blue and white under fluorescence. The homogenization temperature of inclusions showed unimodal characteristics, and the peaks was 110℃~130℃. Combined with the analysis of the burial and thermal evolution history of the study area, the Permian volcanic reservoirs in the western Sichuan basin have experienced hydrocarbon accumulation periods, the period occurred in the Early Triassic (245~243Ma present), which is the main hydrocarbon charging period.
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Screening formation for saline aquifer CO2 geological storage based on entropy weight TOPSIS method - A case study of the northeastern Ordos basin
Li Peng, QU Hongjun, MA Jinfeng, LI Yan, WANG Guiwen, SUN Xiaohan
Abstract:
Objective: Saline aquifer CO2 geological storage is an important reserve technology for achieving carbon neutral-ity. Screening suitable formation is a prerequisite for the site selection of saline aquifer CO2 geological storage projects. The northeastern part of the Ordos Basin, a high carbon emission area, was taken as an example. Methods: And the geological characteristics of 4 potential storage reservoir-cap combinations was analyzed. Based on the three criteria of storage potential, safety and economic and engineering suitability, 14 screening in-dicators were established for saline aquifer CO2 geological storage. The entropy weight method was used to ana-lyze the weights of different indicators, and the final screening is carried out based on the TOPSIS method. Results: The analysis results show that the weights of the 14 screening indicators are between 4.72% and 13.29%, among which the cap thickness has the highest weight, and the reservoir burial depth, reservoir permea-bility, caprock breakthrough pressure, and cumulative reservoir thickness have relatively high weights. The TOP-SIS method ranking score results show that the middle and upper storage reservoir-cap combinations is the most suitable CO2 saline aquifer geological storage in the northeastern part of the Ordos Basin. Conclusions: The middle and upper storage reservoir-cap combinations should be used as the planar site se-lection and subsequent saline aquifer CO2 geological storage project optimization formation.
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The analysis of coal macerals and its application in paleowildfires
Abstract:
The Chinese National Standard for the definition and classification of coal macerals has been completed over 33 years (1980-2013) since the establishment of the Coal Petrology Group of the China Coalfield Geology Professional Committee, while the International Standard “ICCP system 1994” was completed over 26 years (1991-2017) by the International Committee on Coal and Organic Petrology (ICCP). However, after decades of development, there are still many differences in classification schemes at home and abroad. By comparing the Chinese classification scheme of bituminous coal maceral and “ICCP system 1994”, it is found that the evolution differences of the Chinese tertiary classification scheme are mainly reflected in the specific classification categories, whereas the differences at home and abroad are mainly reflected in the maceral classification categories and causes of the vitrinite and the liptinite. It is suggested that reasonable scheme can be selected by scholars according to studying habits and communication object. However, it is necessary to clarify the maceral and sub-maceral types under different classification schemes. As the most common and important maceral group in coal, inertinite can serve as an indicator for the occurrence of paleowildfires. The combustion temperature can be calculated based on the reflectivity of fusinite in the inertinite to determine the intensity and type of paleowildfires. The content of paleooxygen can be determined based on the relative content of inertinite. The retention and sedimentation of inertinite in the atmosphere and lithosphere can reflect the impact of paleowildfires on paleoecology. As an important influencing factor on paleoecology, paleowildfires can reveal information on the composition of the palaeoatmosphere and the succession of paleoecology communities through the analysis of macerals in coal. To some extent, this can help human explore the current global climate warming and the reasons for paleontological extinction during the key geological boundary.
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Evaluation of the suitability of underground space development in coastal cities based on different combination weighting methods
liyueheng, liuhonghua, dishengtong, dongjie, zhanghui, yupeng
Abstract:
With the rapid development of social economy and urbanization, urban spatial resources are becoming increasingly strained, making the gradual exploitation and utilization of urban underground space an urgent necessity. Assessing the suitability of such development is a critical first step. Coastal cities, being economic powerhouses and key nodes for external communication, have a more pressing need for urban spatial resources. Additionally, due to the complex influences of the marine environment, the suitability evaluation of underground space development in these cities is both intricate and essential. This paper focuses on the coastal area of Weibei Plain in Weifang City as its research background. It employs four different combined subjective-objective weighting methods of the improved structural CRITIC, game theory, minimum relative information entropy, and multiplicative synthesis method to empower. Based on the spatial analysis function of ArcGIS, it carries out a comprehensive suitability evaluation and comparative analysis of the underground space development in the research area. The results demonstrate:(1) Regardless of which combined subjective-objective weighting method is used, the outcomes consistently indicate that tectonic fractures, groundwater abundance, groundwater depth, and soil-rock layer permeability significantly impact the suitability evaluation of underground space development in coastal cities. (2) the improved structural CRITIC, game theory, minimum relative information entropy exhibit strong correlations, with correlation coefficients of 0.9825, 0.9585, and 0.9093 respectively. These methods scientifically reflect the subjective and objective weights of the various evaluation indexs. (3) In the evaluation results of the suitability of underground space development of coastal cities based on different combination weighting methods, the sum of very suitable and relatively suitable areas accounted for 44.13%, 42.87%, 41.35% and 42.53% of the total area, respectively.(4) Regions found to be very suitable for underground space development are primarily situated in the Shuangwangcheng Ecological Economic Zone in Shouguang City, the western part of Yingli Town, the central area of Gutidi Street in Hanting District, the western section of Zhuli Street, and the intersections of Longchi Street, Kuiju Street, and Duchang Street in Changyi City.
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The ore-forming effects of the Emeishan mantle plume upwelling event: research progress and prospects
Liu Zhicheng, [ ], [ ], [ ], [ ], [ ], [ ], [ ]
Abstract:
The Emeishan mantle plume has always been a hot research topic of scholars at home and abroad, but the scholars ' research on the Emeishan mantle plume is mostly focused on its own basic theoretical research, and the research on the metallogenic effect is relatively weak, especially the research on the indirect mineralization of the Emeishan mantle plume. In order to supplement and improve the Emeishan mantle plume metallogenic system, this paper systematically summarizes the research results in recent years, and summarizes the characteristics and genesis of various deposit types. On this basis, the temporal and spatial distribution and evolution history of the deposit are combed, and the research focus and prospecting direction of the future Emeishan mantle plume metallogenic system are proposed. First of all, according to the time relationship between the mineralization and the upwelling of the Emeishan mantle plume, it is divided into two types : 1 The mineralization directly related to the Emeishan mantle plume is consistent or later ; 2 The mineralization indirectly related to the Emeishan mantle plume, and the mineralization was obviously intermittent with the upwelling of the Emeishan mantle plume in time, but it had indirect genetic relationship with the Emeishan mantle plume ; the types of deposits directly related to the Emeishan mantle plume include magmatic deposits and hydrothermal deposits. The former includes the Cu-Ni-PGE magmatic sulfide deposits related to the fusion of mafic-ultramafic magmatic sulfides, the V-Ti-Fe magmatic oxide deposits related to the crystallization differentiation of mafic-ultramafic magma, and the volcanic Fe deposits related to the volcanic eruption of overflow basalts. The latter is Nb-Ta-Zr-REE deposits related to syenite veins. The types of deposits indirectly related to the Emeishan mantle plume include the types of deposits that provide mineral sources, the types of deposits that provide ore transport channels, and the types of deposits that provide metallogenic space. They include six types of deposits, namely, modern weathering crust type, modern sand type, ancient weathering crust type, ancient weathering crust-sedimentary type, sedimentary type and hydrothermal type. The types of REE deposits of carbonate-feldspar complex in Panxi area, oil and gas deposits, and coal-copper-rhenium-molybdenum deposits and oil and gas deposits in Panxi ancient rift. Secondly, the spatial and temporal distribution and evolution history of the deposit are analyzed. The study shows that the metallogenic age of the deposit directly related to the Emeishan mantle plume is basically consistent with the formation age of the Emeishan large igneous province. The deposit is mainly distributed in the north-south fault zone, which is closely related to the magmatic channel, and has metallogenic zonation in the vertical direction of the magmatic channel. The metallogenic epoch of deposits indirectly related to the mantle plume of Emeishan is obviously lagging behind the formation age of Emeishan igneous province, and the metallogenic epochs of various deposits are relatively dispersed. In space, they are mainly distributed in the middle and outer zones of Emeishan igneous province, and have the characteristics of dispersion and horizon. The evolution history of deposits directly related to the Emeishan mantle plume is closely related to the magmatism and hydrothermal processes occurring at different spatial locations in the magma channel during the upwelling of the Emeishan mantle plume. The evolution history of deposits indirectly related to the Emeishan mantle plume is closely related to the provenance layer or the initial enrichment layer of metallogenic elements, paleo-deep faults and ore storage space provided after the formation of the Emeishan igneous province, and different deposit types have different evolution characteristics. In this paper, it is believed that the Emeishan mantle plume metallogenic system has bred most of the key minerals such as rare, rare earth, scattered and rare precious metals. The deposit types are diverse and the metallogenic potential is large. It is suggested that the research on the metallogenic theory, metallogenic mechanism, metallogenic prediction, comprehensive recovery and utilization technology and diversified prospecting of metallogenic elements of the Emeishan mantle plume metallogenic system should be strengthened, which can greatly improve the guarantee ability of key minerals in China.
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Fig.1 Simplified tectonic geology and distribution of magic-ultramafic intrusion belts in Beishan area(modified from Pu peng et al., 2018)
ZHAO Binbin, Yu sheng, chengshiqiang, Zhang qin chuan, wang yong qiang, chen jin
Abstract:
Cheng Xuan is an Ore-endowed mafic-ultramafic intrusions discovered in recent years in the Beishan orogenic of Gansu, which is highly similar and comparable to a series of magmatic deposits in the Beishan Mountains of Xinjiang in terms of the age of mineralisation, mineralisation characteristics, and ore-endowed rock phases. The discovery and systematic study of this deposit will kick off the exploration and study of magmatic copper-nickel ores in the Beishan orogenic belt of Gansu. The results of physical and chemical exploration show that the ore-bearing basic-ultra-basic rock body has the characteristics of high weight, high magnetism, high polarisation, medium-low resistance, and good Cu and Ni anomalies, etc. At the same time, combined with the age of metallogenicity, mineralised rock phases, types of mineralisation, and alteration characteristics, it proves that Chengxuan deposit is a typical Cu-Ni magmatic sulphide deposit formed in the Permian Period (295.6Ma).
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Wang Chongyou"s Contribution to the Geological Society of China
Abstract:
In the founding and early history of the Geological Society of China, Zhang Hongzhao, Ding Wenjiang, Weng Wenhao, Li Siguang and A.W.Grabau all made fundamental contributions. After Zhang Hongzhao, Ding Wenjiang and Weng Wenhao successively served as presidents of the Geological Society of China, Wang Chongyou served as the fourth president. By referring to the information and published articles about Wang in the Annals of the Geological Society of China and the Geological Review, and on the basis of referring to other limited materials, this paper sorts out and studies Wang"s contributions to the establishment of the Geological Society, the alleviation of financial difficulties, the establishment of book purchase funds, the establishment of the Grabau Medal and other academic aspects. To understand his efforts in the Geological Society of China and the hardships of the early development of the Geological Society of China, in order to commemorate the outstanding figures in the century long development of the Geological Society of China.
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Sedimentary characteristics of barrier sandbars in the Benxi Formation of Ganquan Fuxian area
Wan Yongping, Song Ming, She Yinnan, Pu Renhai, Fan Yujie, Yang Yunjing
Abstract:
The natural gas reservoir of the Benxi Formation in the Fuxian to Ganquan is mainly composed of barrier sandstone. Under the condition of a dense well network with an average well spacing of 2-3km, drilling data revealed the vertical and horizontal microfacies combination and distribution characteristics of barrier sandbars. This article analyzes the distribution of sandbodies, microfacies types and combinations, profile structures, and sedimentary characteristics of the Benxi Formation barrier sandbars in the Ganquan - Fuxian area based on core, logging, outcrop, and thin section data. The results indicate that both the Ben 1 and Ben 2 Member of Benxi Formation occured two northwest extending barrier sandbars parallel to shorelines, distributed along the slopes between ancient karst grooves and highlands. The barrier sandstone is thickened in a bead like manner, with a maximum sandstone content of about 50%, and a maximum thickness of 22m for a single layer of sandstone. The width of the barrier is generally 3-10km, with a length exceeding 40km, extending beyond the study area. Under the combined action of low to medium tide and weak waves, barrier sandbars are often composed of inlet fine gravels, tidal-channel-like sands, shoal-like sands, and washover-fan sands from bottom to top. The tidal inlet is generally composed of fine-grained conglomerate and coarse to medium sandstone containing mud-gravels, with a scour at the base. The tidal-channel-like microfacies located in the middle and lower parts of the barrier are mostly composed of unidirectional tabular cross-bedded and parallel bedded medium to fine sandstone, occasionally seen bi-directional herringbone cross-bedding. The shoal-like microfacies located in the upper part of the barrier sandbar are generally composed of parallel bedding and low angle wedge-shaped cross-bedded fine sandstone, occasionally seen biological disturbances, etc. Fine sandstones in washover fans generally contain mud-gravel caused by storms. Barrier sandbar change into thin interbedded sand and mudstone of tidal flat or ebb and flood tidal delta laterally, or into swamp coal seams or lagoon mudstones. There are four types of logging facies related to barrier environment: box shaped, funnel shaped, bell shaped, and toothed, with toothed and box shaped being the most common. Sandstones in barrier environments have high compositional maturity and moderate to low structural maturity.
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Quantitative analysis of ancient glacial geomorphology based on UAV LiDAR technology - A case study of Kuzhaori Moraines at the Southern edge of paleo-Daocheng Ice Cap
Li Yiman, Zhang Zhigang, Zhang Hong, Guo Fei, Zhao Dan, Lu Nanxin, Zhang Hongmei
Abstract:
Paleo-glacial landforms serves as an important carrier for understanding Quaternary environmental evolution. The high-precision data from unmanned aerial vehicle (UAV) LiDAR technology allows for the study of paleo-glacial landforms with higher resolution, which can significantly improve the precision of paleo-glacial landforms analysis and glacial landforms mapping. Located on the southeastern edge of the Qinghai-Tibet Plateau, the paleo-Daocheng ice cap preserves rich ancient glacial remains, making it an ideal area for studying glacial geomorphology. In this study, UAV LiDAR technology were applied to conduct aerial surveys of the moraines at the outlet of a glacial valley in Kuzhaori area, located at the the southern edge of the paleo-Daocheng ice cap. The survey yielded Digital Elevation Model (DEM), Digital Orthophoto Map (DOM) and 3D point cloud data of the Kuzhaori moraines. Furthermore, the DEM imaging effects with resolutions of 12.5m and 30m were compared, and the morphological features of the Kuzhaori moraines, as well as the morphological parameters of the valley enclosed by the moraines at the glacial valley outlet, were analyzed. The results indicate that: (1) UAV LiDAR technology can rapidly acquire high-quality, high-resolution data suitable for small areas and complex terrain. Combined with the three-dimensional model can improve the understanding of moraines, glacial troughs and valleys geomorphological morphology; (2) Statistical analysis of topographic features of moraines at Kuzhaori reveal that innermost K-Moraine1 has the second highest average slope, while the K-Moraine6, as an independent moraines, has the highest average slope; (3) The power function exponent b values of the valley enclosed by the moraines at the Kuzhaori glacial valley outlet range from 0.24 to 0.54, which is lower than those observed in most glacial valleys; V-index results range from 0.52 to 0.69. This study provides a good research case for quantitative analysis of glacial geomorphology based on UAV LiDAR technology.
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Formation mechanism of brackish groundwater in the Sandu River basin in upper reaches of the Weihe River
ZHANG Yanlin, LI Jiyu, ZHAO Cheng, LI Chunliang
Abstract:
Objectives: Sandu River basin in the upper reaches of the Weihe River is a well-known distribution area of brackish groundwater in the Loess Plateau. The social and economic development of the region is constrained by the issue of “pollution induced water shortage”. Make an intensive study of the formation mechanisms in brackish groundwater is of great significant to the rational development and utilization of groundwater resources, as well as ensuring drinking water safety. Methods: In this paper, it takes the water chemical detection data collected from 26 sites in the middle and southern parts of the San Du River basin as the research foundation. The hydrochemical analysis, correlation analysis, ion ratio analysis and mineral saturation index analysis were investigated to identify the hydrochemical characteristics and ion sources of groundwater in the Sandu River Basin, and discuss the formation mechanism of brackish groundwater. Results: The results show that phreatic water of river valley was generally brackish water, the average values of total dissolved solids ( TDS ) and SO42- are 5599.7 mg/L and 1973.1 mg/L respectively in the research area. The hydrochemical types are mainly HCO3-Na, HCO3?SO4-Na, SO4?Cl-Na?Mg, Cl?SO4-Na?Mg, and SO4?Cl-Na. In addition, the distribution of brackish water is closely correlated with the meizoseismal area of “Tongwei earthquake” in history. The phreatic water of loess is a recharge area for regional groundwater in the study area, with a short and intense circulation pathway, and better water quality than the phreatic water of river valley. The TDS are 839.6~1237.6mg/L. The hydrochemical types are mainly Cl?SO4?HCO3-Na, HCO3?Cl-Na and HCO3?SO4?Cl-Na. Conclusions: The hydrochemical compositions of groundwater mainly come from the weathering and dissolution of gypsum and halite; Lixiviation is the main controlling factor for the formation of brackish goundwater in the study area, followed by cation exchange, but evaporation and human activities have a slight impact; The increase in soluble salts in valley deposits and changes in the conditions of groundwater runoff caused by the Tongwei earthquake is the root cause.
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Characteristics and Significance of Bromine Content in Tibetan Salt Lakes Brine and Its Evaporation Process
WANG Xinyuan, CHEN wenxi, LI Shengqun, ZHAO Yuanyi
Abstract:
Bromine is one of the important chemical raw materials in China, with important research and application value in environmental science and industrial fields. In recent years, with the bullish market of chemical products such as bromine flame retardants and bromine salts, the demand for bromine will continue to grow. The chemical composition of brine in Tibetan Salt Lakes has always attracted much attention, of which the content of bromine (Br) is also an important indicator. However, at present, there is little research on the distribution of bromine (Br) in Tibetan Salt Lakes and the content characteristics and significance of bromine in the evaporation process. This paper takes Tibetan Salt Lakes as the research object, studies the content characteristics of bromine in brine, and discusses its changes in the evaporation process. The research shows that: ①The bromine content in the brine of Tibetan Salt Lakes is 0.11~187.03mg/L, and most of the salt lakes are rich in Br, such as Zhacangchaka (52.90mg/L) and Nieercuo (52.03mg/L), whose Br content is higher than the comprehensive evaluation index of bromine (50mg/L); The Br content in the brine of Zhabuye North Lake (187.03mg/L), Zhabuye South Lake (177.80mg/L), and Dangxiongcuo Salt Lake (106.62mg/L) is higher than the boundary grade of bromine in Zhabuye Salt Lake (100mg/L). Within a year, Zhabuye North Lake and South Lake have the highest bromine content in November and December, with 212.23mg/L and 272.78mg/L, respectively; In July and August, the highest bromine content was found in Dangxiongcuo, with a maximum of 130.00mg/L; ②The main source of Br supply in salt lake brine is strongly active hot springs, which converge through river water and accumulate in salt lake brine. Among them, about 99% of Br supply in Jiezechaka salt lake brine comes from riverside hot springs; ③Although the Br content in salt lake brine is far lower than that in seawater, the Br content in salt field brine, such as in various levels of salt fields in Zhabuye, is significantly higher than the industrial extraction grade (300mg/L). During the natural evaporation and concentration process of brine, the content of Br gradually increases with the increase of evaporation rate. The concentration of bromine in the brine of Zhabuye Salt Lake increases from 90.00mg/L of the original brine to 420.00mg/L when the evaporation rate is 79%; When the concentration of bromine in the brine of Dangxiongcuo Salt Lake increased from 107.40mg/L of the original brine to a evaporation loss rate of 84%, it was concentrated to 303.50mg/L. Salt lakes and salt field brine with high bromine content are potential resources for the comprehensive development and utilization of bromine.
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Sedimentary environment and genetic analysis of Late Paleozoic aluminous argillites in Zhangji coal mine, Huainan
LV Dawei, LI Zekuan, SHEN Xiaoli, ZHANG Zhihui, Liu Haiyan, WANG Luojing, ZHANG Aocong, LI Qing, WU Dun, LIU Xiaolong
Abstract:
Objectives:Huainan is located on the southern margin of the North China Craton, where developed aluminous argillites in the Late Paleozoic Benxi Formation. At the same time, there are thicker aluminous layers in the western Henan area, which is located on the southern margin of the North China Craton. By exploring the differences in mineralization between the two regions, it can provide a better scientific basis for the exploration of aluminous deposits. Methods:This article has conducted XRD, major and trace element analysis, and zircon U-Pb dating tests on the Benxi Formation aluminous argillites in Zhangji coal mine,Huainan, analyzing its geochemical characteristics and genesis, and comparing it with the formation conditions of bauxite in western Henan. Results:Detrital zircon U-Pb dating data show that the peak ages are mainly concentrated in~311.5ma,~451.5ma,~925.75ma,~1753.5ma and~2488.5ma. Compared with the peak ages of zircon in the provenance, it is revealed that the provenances of aluminous argillites are mainly igneous rocks in the North Qinling orogenic belt and metamorphic rocks and igneous rocks in the basement of the North China Craton. In geochemical analysis, Li element is obviously enriched; The range of Sr/Cu is 3.51~45.8, and the range of B/Ga is 13.8~27.9; The SR/BA range was 1.7~16.9 and the V/(V+Ni) range was 0.76~0.92; Geochemical indicators show that aluminous argillites was formed in arid tropical climate and deposited in marine reductive environment. Conclusions: By comparing the genesis of aluminum argillites in Zhangji coal mine in Huainan and bauxite in western Henan, it is concluded that the metallogenic differences between the two regions are mainly caused by climate and transgression events. Less precipitation and transgression raise the groundwater level, resulting in the deposition of aluminum argillites in an environment with weak leaching and stagnant water, which leads to the lack of further enrichment of Al element and failure to mineralization. Under this condition, Li element is enriched in clay minerals in aluminum argillites. Therefore, bauxite is more likely to develop in areas less affected by marine transgression. According to the distribution of paleosedimentary environment in Huainan area in Benxi period, the metallogenic prospect of bauxite in Huainan area is mainly developed in tidal flat and delta sedimentary environment in the West and north of the study area. At the same time, Li element is relatively enriched in the associated elements of aluminous argillites, which has a certain metallogenic potential
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Li and Ga enriched layers of key metals were found in Permian Liangshan Formation in Bijie area of western Guizhou
lizhiwei, zhanghonghui, lidezong, wangdonghui, zhangqidao, zhaoruigang, yuyifan, zhuxingqiang
Abstract:
无
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Characteristics and significance of volcanic ashes in some strata in western Guangxi
Zhang QiLian, Wang Xueheng, Deng Jun, Wei Fang, Cheng Wenlen, Li Huosong, Gong Yan, Li Yuken, Yang Kuai, Xin Xiaowei
Abstract:
Objectives:There are any studies on volcanic ash in platform facies of Paleozoic scarcely, so as to hinder further study of tectonic evolution. Methods: line investigation, microstructure and element geochemistry Results: we found that volcanic ashes exists in the silty mudstone of Tangjiaba Formation of upper Cambrian, and the bauxite series of Du 'an Formation of lower Carboniferous Series, and the aluminium-bearing rock series of lower upper Permian series and superimposed clastic rocks, all of volcanic ashes developed resorption and devitrified structures.The volcanic ashes of upper Cambriancan display fine quartz porphyry, feldspar baby-crystal, spherules and white glass that represent distant rhyolite volcanic ash. Plagioclase and pyroxene are the main phenocrysts in the Lower Carboniferous volcanic ash, adding yellowish brown glass, whereas the geochemical characteristics of the zircon and the the rock elements show that they are alkaline basalts, and the detritus present that the ashes come from the near basaltic volcano. The volcanic ashes in the lower upper Permian are distributed in the terrestrial aluminite rocks and the overlying transgressive clastic rocks, and the volcanic ashes in the aluminite rocks are mainly basalt-Andesitic, whereas the ones in the clastic rocks of the roof are mainly rhyolitic, and the ones in the limestone below the P/T boundary are mainly rhyolitic, and the assembly of basaltic, Andesitic to rhyolitic, just means that it derived from the island arc which was inferred adjacent by the existence of detritus. Conclusions: By volcanic ashes it can be concluded that western Guangxi was of passive continental margin of the northern part of the Indian Plate in late Cambrian, and the acid volcanic ashes come from the arc volcano of the Indo-Australian Kuungan suture, and when it came to early Carboniferous period the west Guangxi was located within the Youjiang rift basin lying southwest margin of the Yangtze plate and volcanic ashes come from the regional volcanic eruption, and in the late Permian, the western Guangxi developed into back-arc basin and accepted volcanic ashes from the Paleotethyan island arc.
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2013,59(6):1097-1109, DOI:
Abstract:
There are no efforts have been made for the classification of internal wave and internal tide deposits for more than twenty years since they were discovered in the geological records. Here we try to propose a classification of internal wave and internal tide deposits based on the types which were already discovered in sedimentary rocks as well as the breaking processes of internal waves and its development research in physical oceanography. There are nine types through three orders, which include barotropic internal tide deposits, baroclinic internal tide deposits, barotropic short period internal wave deposits, baroclinic short period internal wave deposits, contour currents interaction internal wave deposits, low density turbidity currents interaction internal wave deposits, long period internal wave interaction deposits, standing internal wave deposits and other internal wave interaction deposits. The discovering internal wave and internal tide deposits in geological records are attributed into barotropic internal tide deposits, barotropic short period internal wave deposits and long period internal wave interaction deposits. And the other six types are still unrecognized. The classification proposed here perhaps give a reason for the phenomena that internal waves occur nearly ubiquitously in oceans yet their sedimentary records remain largely unrecognized. Furthermore, this classification is help for connecting the deposits of internal waves not only with its research in physical oceanography, but also with the oceanic unexpected events, ocean circulation and astronomical period in geological history.
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丁一, 李智武, 冯逢, 翟中华, 孙玮, 汤聪, 张葳, 张长俊, 刘树根
2013,59(2):389-400, DOI:
Abstract:
The Daanzhai Member of the Lower Jurassic Ziliujing Formation is one of the major oil production horizons in Sichuan Basin, where "pure" limestone from high energy shelly shoal of shallow lake facies has been usually viewed as the only kind of reservoir rock in previous studies. Based on outcrop surveying and borehole core observation as well as thin section and SEM (scanning electron microscopy) analyses, we propose in the paper that the Daanzhai Member of Ziliujing Formation is a typical lacustrine depositional sequence of mixed siliciclastic—carbonate sediments in Longgang area, central Sichuan Basin, which contains two levels of implication. In narrow sense, the mixed siliciclastic—carbonate rock means mixing of major lacustrine carbonate with minor terrigenous clastics and/or clay in various proportion. Main rock types consist of shelly limestone, sandy/silty/argillaceous shelly carbonate, calcareous shelly sandstone/siltstone/mudstone/shale, etc. In broad sense, the mixed depositional sequence implies alternating layers of shelly limestone, mudstone/shale, sandstone/siltstone and mixed siliciclastic—carbonate rock with unequal thicknesses. In general, there are three ways of mixing: punctuated mixing, in situ mixing and facies mixing, which are respectively controlled by storm wave action, hydrodynamic condition and predominant facies. Both relatively pure shelly limestone and mixed siliciclastic—carbonate rocks are extremely tight. Almost all primary porosity has disappeared because of intense compaction since burial. The present pore spaces are largely composed of dissolution pore, dissolution micropore, microfracture and structural fracture, etc. In addition to "pure" shelly limestone, some silty/argillaceous shelly limestone and shelly siltstone/mudstone/shale with relatively good porosity and permeability could also serve as one kind of effective reservoir due to better developed microfractures within them. These observations and drilling results imply that the silty/argillaceous shelly limestone of low energy shelly shoal and surrounding shelly siltstone/mudstone/shale adjacent to hydrocarbon generating center are extensively developed and potential reservoir. This is particularly important for tight oil exploration, which should be paid special attention to. Therefore, a pilot exploration is recommended to be carried out.
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2014,60(4):851-857, DOI:
Abstract:
The Laos’s salt bearing Basin was located in the southeast of new Tethys domain during Cretaceous and hosted huge potash deposit during late Cretaceous. δ34SV CDT of anhydrite from borehole of Thakhek basin located in the southeastern Vientiane with value of 13.8‰~15.3‰ is similar to that of contemporaneous marine evaporites that indicated these anhydrites were with marine origin. These evidences further prove that the potassium materials in both the Laos’s salt bearing basin sourced from Cretaceous seawater with the mixture of fresh water from land. Combining with the update data that the time of potash deposition in both the Laos’s salt bearing basin and Simao basin was approximated and sulfur isotopic composition of Mengyejing Formation,we inferred that the sulfur isotopic composition in both the Laos’s salt bearing basin and Simao basin were consistent with that of contemporaneous sea water and proposed a preliminary scenario that the two basins were possibly connected when marine transgression happened.
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2005,51(6):681-693, DOI:
Abstract:
According to the concept of ophiolite in 1 970s,exposure of marie—ultramafic rocks in the orogenic zone hasbeen interpreted to represent the relic of fossil ocean lithosphere based on its lithology units consisting withoceanic crust and upper mantle.So the ophiolite is a key e.vidence of boundary between the fossil plates,and hasbeen played an im portant role on the formulation and advancement of the plate tectonic theory. Recently,ophiolite is divided into M OR—and SSZ—types based on the formation tectonic setting. M OR-type ophioliteformed at Mid—ocean ridges(M oR),and SSZ—type ophiolite formed on the supra—subduction zone caused bythe ocean—continent subduction or intra—ocean subduction.and there are obvious difference in mantle sequence,cumulated assem blage and lavas in petrology, mineralogy and geochemistry between M OR— and SSZ—typeophiolites.This classification explains well the various ophiolites and the difference between the ophiolite andoceanic lithosphere.During the subduction of oceanic lithosphere,the M OR—type ophiolite was subducted,or ispreserved only as dismembered thrust sheets or blocks in ophiolitic m61ange,while SSZ—type ophiolite,asfragments of modified oceanic or rebirth lithosphere caused by fossil oceanic plate subduction,is commonlypreserved in the orogenic zone due to it formed above subduction zone.Therefore,SSZ-type ophiolite is majorone preserved well in the orogenic zone.Also discussed in this paper are the problems in the ophiolite study,such as the difference between the ophiolite and ocean lithosphere in peridotites.and the methods to solve theseproblems. And the pre—Rodinia super—continent ophiolite record is still considered poorly understanding,andwhether Archean greenstone is ophiolite or not.These are all questions to answer.
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2014,60(1):1-21, DOI:
Abstract:
Based on geophysical investigations of worldwide crust and upper mantle, this paper analyzes ocean—continent transition process and lithospheric thickening process. The ocean—continent transition process contains five stages: ① crustal thickening during co expansion of an ocean, ② trench formation of and early subduction, ③ mature subduction and formation of trench—arc—basin belts, ④ convergence and migration of subduction zones, and ⑤ island—continent collision and connection to a continent. Geophysical profiles show that the crustal thickening during co expansion occurs in passive continental margins, sedimentation, magma underplating and ultra pressure hydraulic fracturing resulting in formation of trenches. After formation of trenches the passive continental margins become active, tectonic mechanics tends to subduction. In the mature subduction stage the expansion of ocean basins keeps compensation with the crustal shortening of the subduction, while opening of back arc basins or marginal seas indicates the mature subduction stage. During the post mature subduction stage, marginal sea micro plates are narrowing and subduction zones are convergence and migrating. Crowded and short subduction zones with different subduction directions can cause local extension basins, they all mix together. As crustal thickening and gravity equilibrium go on, the arc belts would uplift and finally connecting to a continent via island—continent collision, becoming a special unit of continental lithosphere, i.e. the phanerozoic eon ocean—continent zone.
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SHU Liangshu, ZHOU Xinmin, DENG Ping, YU Xinqi
2006,52(2):251-265, DOI:
Abstract:
南岭构造带发育在强烈褶皱变形的基底之上,发育了华南地区最大规模的早中生代花岗岩和裂谷盆地。基底由变质的新元古代一奥陶纪复理石一火山岩系和未变质的晚泥盆世一早三叠世沉积岩系所组成。与南岭带构造演化关系最为密切的区域断裂带有萍乡一桂林、龙岩一海丰、赣江等5条,制约着中、新生代岩体和盆地的分布、规模和产状。无论是物质来源还是形成与演化的动力学背景,南岭构造带均离不开其北面的大别造山带和南西面的印度支那造山带。南岭地区存在3条近东西方向的花岗质岩带,严格受深部构造制约,岩体常受褶皱和断裂构造控制。3个花岗岩带中的岩体时代,具有横向上北老南新、走向上西老东新、朝大洋方向年轻化的迁移演化规律,中生代东西向的花岗岩带是在古特提斯构造域近东西向的断裂带基础上发育的,岩浆热隆伸展构造和变质核杂岩多数发育在两组大断裂的交汇处。在研究区厘定出3种基本盆地类型,晚三叠世-早侏罗世发育类前陆盆地,中侏罗世发育裂谷盆地,早白垩世属火山-沉积断陷盆地,晚白垩世以来则几乎全是箕状断陷盆地。前中侏罗世盆地构造主要受特提斯构造域和印支期碰撞的影响,晚侏罗世以来盆地构造则主要受太平洋构造作用和陆内深部构造的联合制约。武夷山是晚中生代的古地理与气候分隔带;赣江带是晚中生代的火山岩界线;闽西-赣南-粤东地区存在一个近东西向的中侏罗世陆内裂谷带。区内存在3种盆一岭耦合类型:挤压逆冲型(少量)、走滑剪切型(少量)和伸展拆离型(大量)。中、新生代盆地构造和花岗岩山岭有着密切的时空与成因联系,共同构成了华南盆岭构造体系。最后对前中生代构造作用、印支期构造事件、两种构造体制的转换等问题进行了探讨。晚泥盆世-中三叠世研究区为浅海-滨海环境,几乎没有岩浆活动,龙潭期曾区域抬升为陆,地质事实不支持华南东部存在晚古生代深海洋盆的观点;南岭地区J2和J3之交形成的两类不同力学性质、岩石组合、应力场特征的盆地构造,是特提斯向太平洋构造域转变的宏观标志;南岭东段是这两种构造体制叠置和转换的重要位置之一。
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王杰, 任军平, 何胜飞, 许康康, 刘晓阳, 左立波, 孙凯, 龚鹏辉, 贺福清
2014,60(5):997-1008, DOI:
Abstract:
South Africa is one of the countries with the richest gold ore resources in the world.The gold deposits mainly occur in the northeast of the South Africa.Three types of gold ores have been recognized,which are: ① Witwatersrand conglomerate type gold deposits; ② granite greenstone belt type gold deposits; and ③ dolomite type gold deposits,with the former two types being the major ones in the region. Witwatersrand conglomerate type gold deposits are high grade,maximum deposits yield, large scale and very depth and are the most important types in South Africa.The genesis of the deposits is controversial.Two different models occur which include placer mode and thermal fluid model.According to the current data the writers think they represent two different mineralization stages. Granite greenstone belt type gold deposits mainly occur in the Barberton area which are large scale, easy mining and other characteristics, therefore which occupies an important position in the South African. The deposits are mainly hosted in quartz veins or shear zones. Three different models occur which include volcanogenic mineralisation models, inverted decollements modes and structure intersection model.
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WANG Zhaobo, BIAN Qing, LI Dapeng, WANG Jinyu, LIU Cailing, GUO Qipeng
2017,63(1):134-142, DOI:
Abstract:
In this paper, the characteristics of the Quaternary glacial moraine and related relics found in Mount Mengshan, Shandong Province, are systematically introduced. The authors concentrate mainly on the moraines, scratches, polished surface and chatter marks distributed in Lanxi valley. At the same time, the distribution, size, composition and rock characteristics of the lateral moraines and felsenmeers are reported. Based on the distribution of the lateral moraine and the weathering degree of gravels, we are trying to identify the moraine traces as the product formed at the last glacial period. Based on measurement and statistical analysis of the scratches on the polished bedrock surface from both sides of the valley, the length/width ratio of scratches on valley walls is about 10:1. Using lateral moraine maximum height method and investigation with lateral moraine at Mount Mengshan region, we have estimated the height of the last glaciation snow line in the southern slope of Mount Mengshan. It is about 700 meters.
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2013,59(6):1131-1142, DOI:
Abstract:
A suit of metamorphic rock series are largely outcropped in Geyading—Maoding area, Jinsha Suture, northwestern Yunnan Province. The rocks include quartzite, sericite—quartz schist,amphibolites, mica schist and marbles. The depositional age of the metamorphic rock series has long been debated. In this paper, sericite—quartz schist and quartzite are measured by the LA MC ICP MS method. The dating of zircons shows that the detrital zircon ages of sericite—quartz have a youngest age of about 205 Ma, a dominant peak at 231 Ma, two subordinate peaks at 214 Ma and 255 Ma, and some lesser peaks at 420 Ma, 502 Ma, 873 Ma, 1.94 Ga and 2.46 Ga; the detrital zircon ages of quartzite have a youngest age of about 332 Ma, a dominant peak at 361 Ma, a subordinate peak at 422 Ma, and the other lesser peaks at 1.40 Ga, 1.56 Ga, 1.72 Ga. These dating results above suggest the protolith of sericite—quartz schist was deposited in the Late Triassic (later than 205 Ma), and the protolith of quartzite was deposited in the Early Carboniferous (later than 332 Ma), which indicate the formation age of the metamorphic rock basement in Geyading—Maoding area, Jinsha Suture, shouldn't be thought to be Proterozoic in age. Besides, the data of detrital zircon population suggest that the provenance of the metamorphic rock series was mainly derived from the Yangtz Block materials.
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2013,59(6):1165-1176, DOI:
Abstract:
The carbonate rocks are widely distributed, whose thermal evolution is generally high and organic matter abundance are lower in China. Whether or not they can be effective source rocks has great significance for the evaluation of hydrocarbon generation potential and exploration prospect of carbonate rocks. Many studies show that as the depth or thermal evolution degree increase, TOC of source rocks decreases, and hydrocarbon generation potential and residual amount increase and then decrease, besides the results of thermal simulation experiment, which indicate the source rocks of low organic matter abundance could can generate and expulse a great number of hydrocarbon. Hydrocarbon sources of some typical oil and gas fields are the carbonate rocks of low organic matter abundance in the world. A few factors could be considered to determine the lower limit of TOC of carbonate source rocks. The analysis suggests the lower limit of TOC of carbonate source rocks is less than 0.5% of mud rocks. The lower limit of TOC of the effective source rocks with different maturity was gained by the method of hydrocarbon generation potential and simulative calculation based on material balance principle according to the hydrocarbon expulsion threshold. Referring to the study results of predecessors and exploration practice, The lower limit of TOC of the effective carbonate source rocks with low maturity, maturity and high—over maturity stages respectively are TOC≥1.4%, TOC=0.1%~1.4% and TOC<0.1%.
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DENG Jinfu, FENG Yanfang, DI Yongjun, LIU Cui, XIAO Qinghui, SU Shangguo, ZHAO Guochun, MENG Fei, CHE Rufeng
2015,61(6):1211-1224, DOI:
Abstract:
For a long time a lot of the models about the tectonic evolution and the orogenic architecture of the Paleo Asian tectonic domain are suggested by many famous geologists. However, there are large divergence of the views, especially about both the space distribution and the closing time of the Paleo Asian Ocean. Based on the intrusive tectonic map of China with the scale of 1:2500, 000, by this paper we would like to join the discussion. (1) The formation of the intrusive arc, and the collisional as well as the postorogenic igneous petrotectonic assemblages is occurred progressively younger from west to east with time, and the trend lines of the main tectonic zones is developed from near east—west in the west to near north—south directions in the east, both of which is suggested the transition of the Paleo Asian Ocean closing to development of the Pacific tectonic domain. (2) The broad trench—arc—basin system developed at the southern margin of the Siberia craton situated in the north of the main oceanic basin; the passive continental margin at the west, and the narrow trench—arc—basin system in the middle, as well as the active continental margin at the east, respectively, developed at the northern margin of the Tarim—North China craton. (3) Both the remnant arc and the oφ since Pt3 is scattered within the main arc, and is regarded as the basement beneath the main arc. (4) The classical “massif” in the orogenic zone is considered to be the remnant arc by this paper, because they are intrusive arc formed in the early stage during the oceanic subduction. (5) The main oceanic basin is recognized from three signs by this paper, (a) The closing of the ocean is latest, (b) The oceanic subduction is bidirectional when the active arc at both the sides, or is developed at one side when one side is active continental margin, and the other side is passive continental margin, (c) The long live and the residue ocean of the Mediterranean sea type are developed as the early stage of the continent—continent collision. (6) A lot of both the intrusive arcs and the oφ during Pt3—T support the formation of the large amount of the juvenile continental crust by Sngor et al., as well as is corresponded to the positive value of the εNd(t) for the granites, which, in turn, is suggested to be formation of the large amount of the oceanic subduction resulted in the cooling of the mantle, and the adding eclogites into the mantle, finally, the high density mantle flow is formed as the dynamic source for the closing of the Paleo Asian Ocean and then the collision between the Siberia and the Tarim—North—China cratons.
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HAO Yanli 1), ZHANG Zhaochong 1, 2), WANG Fusheng 1), John J. MAHONEY 3) 1) Institute of Geology, Chinese Academy of Geological Sciences, Beijing, 100037 2) China University of Geosciences, Beijing, 100083 3) School of Ocean, Earth Science, Technology, University of Hawaii, Honolulu, HI 96822, USA
2004,50(6):587-592, DOI:
Abstract:
Analyses of basalts from the Emeishan large igneous province show that the TiO 2 contents of them are variable continuously. And outcrops of high Ti and low Ti basalts in field are unzoned spatiotemporally. The similar Sr, Nd and Pb isotopic compositions of these two types of basalts indicate that they are comagmatic igneous rocks. The MgO versus TiO 2 diagram for picrites and basalts shows four evolution trends, whose geneses were simulated by the fractional crystallization model. The result suggests that high Ti and low Ti basalts are different products of the same parent magma (picritic basaltic magma) through fractional crystallization of different minerals.
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2016,62(3):693-708, DOI:
Abstract:
As the natural barriers of Beijing and the important junctions connecting Hebei, Shanxi and Inner Mongolia, the Western Hills of Beijing have rich natural resources such as high quality coal and building materials. The Western Hills have been the energy base and important religious holy land of Beijing since 1421 AD, when Beijing was made the capital of the Ming Dynasty. A well developed ancient road system was built for the purpose of connecting the important military facilities, temples, coal mines and hundreds of villages in Ming and Qing Dynasties. A lot of hoof shaped holes with diameters of about 20 cm are scattered along the surface of the manmade ancient roads, which are dozens meters or hundreds of meters higher than the river bed. Typically the holes show clear patterns of animal trails, the distance between two holes averages 40~60 cm. Based on this analysis, the author validated that these holes could not be formed by the processes of grinding action of streams currents to make pot holes nor by differential erosion. They are the stepping holes which were formed by the continuous treading of the hoof shoes of pack animals.
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2012,58(3):533-541, DOI:
Abstract:
Overview the landslide monitoring and early warning researches achievements from three aspects as the rainfall thresholds, monitoring techniques, and regional monitoring and early warning system. Firstly, it summarized the landslide rainfall thresholds of 28 countries or regions in the world including their study or statistic methods. Day rainfall model, antecedent rainfall model and soil moisture content model almost cover all rainfall thresholds calculation methods. On the other hand, due to the complicated water infiltrating and triggering types, different mechanism landslides “need” different thresholds. Study of coupling rainfall to water seepage to soil strength is the trends in the future. The monitoring techniques can be divided into four kinds as the displacement monitoring, physical field monitoring, underground water monitoring, and trigger factors monitoring according to the monitoring objects. It also can be divided into three kinds as manual monitoring, simply equipped monitoring and professional monitoring according to the monitoring devices. At present, the domestic monitoring techniques are closed to foreign countries. Some professional monitoring equipment has become very common. It's limit application only because of the high price. Some new technology such as InSAR, three dimension laser scan can be utilized in the landslide monitoring quickly. The data collecting comes to automatically remote control and monitoring system has a Web—GIS trend. People can design a set of early warning level through combining the susceptibility or hazard zoning map and the rainfall threshold. Installing certain amount of rain gage, plus the forecast rainfall, it can do the landslide early warning then. It is the routine method on regional rain triggered landslide warning whatever domestic or overseas. This kind of early warning played an important role especially on public alert, but it is difficult to warn individual landslide effectively. Landslide monitoring and early warning projects were implemented in China in many places in recent 10 years and got great achievements. But according to the statistic data, the successful warning rate is not so high. One hand is the rate of professional successful alert to total successful alert is very low; another hand is many landslides occurred outside the alerting zone. So the bottleneck problem of restraining the effectiveness of monitoring and early warning is the potential landslides identifying which is the basis of all other measurements. The way to resolve it is to study the landslides regional development regulars to find the effective identifying technology for the potential landslides, and to bring the landslide risk management conception into it, so can distribute the monitoring resources reasonable and to warning effectively.
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2013,59(6):1143-1149, DOI:
Abstract:
The barite deposits hosted in Early Cambrian black shales in South China is one of the representative world famous sediment hosted stratiform deposits. This paper reports the discovery of zoned hyalophane for the first time, based on a case study in the Dahebian barite deposits, Tianzhu county, South China. Analytical results of electron microprobe analysis show that outer BaO content is 1653% to 1786% and K2O content is 777% to 819%, while BaO content is 1204% to 1421% and K2O content is from 860% to 979% in the core. Combined with the geological setting and previous research results, we addressed geological implications of this discovery. It supports the impact of hydrothermal liquid in the formation of the barite deposit. Multiple stages of barium rich fluid participated in the barite formation, and the mineralization was fault controlled, episodic and progressive. This not only further implies the hydrothermal sedimentary genesis of the deposit, but also betters the understanding of mineralization process. These results may have general implications to the other studies worldwide, as the Dahebian deposit is the biggest in volume of such deposits in the world.
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2014,60(2):237-259, DOI:
Abstract:
Based on geophysical lithospheric investigations worldwide, this paper analyzes the continental collision orogenic process. The geophysical lithospheric investigation data as well as physical laws build the foundation for reconstruction of evolution and the deconstruction method for interpretation of deep reflection profiles. Continental collision results in accretion of continents from the ocean—continent transition (OCT) zones. Owing to widely development of the OCT zones, the Alps—Xizang(Tibet) collision orogenic belt belongs to the so called skirt plate collision type, which does not act like elastic collision with no rebounding effects. This type collision usually shows ophiolite but few ultrahigh metamorphic belts on the surface. On the other hand, owing to rarely development of the OCT zones, the Dabie—Sulu collision orogenic belt belongs to the so called nude plate collision type, which acts like elastic collision with rebounding effects. This type collision usually shows ultrahigh pressure metamorphic belts but few ophiolite on the surface. The rebound created conditions for exhumation of the ultrahigh pressure metamorphic belts from deep mantle. Both the skirt plate and nude plate collisions contains mainly four collision stages: (1) pre collision stage involving ocean subduction and closing, (2) pre collision stage, (3) late collision stage or continental to continental subduction stage, and (4) post orogeny stage. At the pre collision stage, the skirt plate collision do not rebound but the nude plate collision does. At the late collision stage, the skirt plate collision does not show the exhumation of the ultrahigh pressure metamorphic belts but the nude plate collision does. The post orogeny stage means gradually stopping the orogeny process, lithospheric stress between continents in collision transfers to extension state from compressional state, resulting the same rotational pore between the two continents. However, lithospheric deformation and detachment can still occur, and convergence of deep heat fluids and magma intrusions would prefer play important roles in the week lithosphere along the collision belts.
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2012,58(1):91-104, DOI:
Abstract:
The Eocene—Oligocene climate transition (EOCT) was a period of rapid global cooling at abou 34 Ma ago, representing a major step from early Cenozoic greenhouse toward modern icehouse conditions. It was accompanied by a series of dramatic changes in Earth's environmental system, including an expansion of ice sheets on the Antarctic continent, a global sea level drop, a declining atmospheric CO2 concentration, a deepening of the calcite compensation depth, and a biotic reorganization, thus has great significance in understanding the mechanisms behind the long term Cenozoic cooling, the behavior of regional climate in response to rapid cooling and the effects of major climatic changes on the biotic reorganization. This review summarizes recent progress in studying EOCT. (1) Significant cooling during this transition inferred from geological records of different latitudes indicates this phenomenon was triggered by global rather than regional factors. (2) The declining of atmospheric CO2 and the associated global carbon cycle changes have been proved as the primary causes of EOCT by modeling studies, rather than the previous hypothesis that the Antarctica was thermally isolated by the initiation of Antarctic Circumpolar Current. (3) Marine records revealed that this transition is marked by a two step increase of benthic foraminiferal oxygen isotope values occurred within 400~500 ka, reflecting the drop of global temperature and establishment of Antarctic ice sheets, respectively. (4) A comparison of the EOCT interval in Asian terrestrial records with marine records suggests that the regional aridification mainly corresponds to atmospheric cooling (i.e., the first step of EOCT) rather than ice volume growth. However, there are still many questions remained unsolved. Future application of more detailed and accurate proxies of atmospheric CO2 and paleotemperature, recovery of high resolution sediment archives from the oceans and continents and more complex models across the EOCT will further reveal the changes of each environmental factor during this transition and their relationship with each other, and obtain a thorough understanding of the mechanisms behind this critical climate transition.
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2013,59(6):1177-1188, DOI:
Abstract:
Landslide inventory is the essential part of regional earthquake triggered landslide studies. In recent years, studies about landslide inventory related with single seismic event are common. However, area and volume error analysis of inventory of landslides triggered by earthquake is still lack. In this paper, a remote sensing image resolution based error analysis method of inventory of landslides triggered by earthquake was proposed. Error analysis of inventory of 2036 landslides triggered by the April 14, 2010 Mw 69 Yushu earthquake, inventory of 30828 landslides triggered by the January 12, 2010 Mw 70 Haiti earthquake, and inventory of 197481 landslides triggered by the May 12, 2008 Mw 79 Wenchuan earthquake were carried out respectively. The results show that area of the Yushu earthquake triggered landslides is 1191 km2, of range from 1153 km2 to 1229 km2, which is error range from 9681% to 10319%; these landslides in a total volume of 2012×106m3, of range from 1947×106m3 to 2078×106m3, in other words, error range from 9677% to 10328%. Area of the Haiti earthquake triggered landslides is 15743 km2, of range from 15118 km2 to 16368 km2, which is error range from 9603% to 10397%; these landslides in a total volume of 29698×106m3, of range from 28594×106m3 to 30821×106m3, in other words, error range from 9628% to 10378%. Area of the Wenchuan earthquake triggered landslides is 1160025 km2, of range from 1072258 km2 to 1248424 km2, which is error range from 9243% to 10762%; these landslides in a total volume of 4693159×106m3, of range from 4372957×106m3 to 5033739×106m3, in other words, error range from 9318% to 10726%. The relation between resolution of the remote sensing and landslide inventory error show that the remote sensing resolution affects on landslide inventory error significantly. Also, the correlation of earthquake landslide frequency distribution and landslide inventory error show that there was a significant effect on landslide inventory error for earthquake landslide frequency distribution. This method of earthquake triggered landslide inventory error analysis can be applied to other more regional earthquake triggered landslides events.
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何付兵, 徐吉祥, 谷晓丹, 程新彬, 魏波, 李昭, 梁亚南, 王泽龙, 黄淇
2013,59(6):1150-1164, DOI:
Abstract:
Amuguleng granite is located at the north of East Ujimqin Banner(Dong Ujimqin Qi) Administration Center in Inner Mongolia. Geological investigation indicates that the granite composing of 2 intrusive rocks: gray yellow medium—fine, medium—coarse grained adamellite containing huge phenocryst and gray white fine adamellite. Zircon U Pb age of the granite dated as 314.2±2.2Ma and 167.1±1.3Ma, suggesting that they were products of magmatic evolution during Late Carboniferous and Middle Late Jurassic respectively. Accessory minerals of both the two granites are rich in magnetite, monazite, and sphene, and there is fluorite in the Mid-Late Jurassic granite. Compositon of the rocks indicates that these two kinds of granites have similar geochemical characteristics: major element are characterized by enrichment of Si, higher DI and NK/A , Fe2O/FeO ratios. The race element spider diagram indicates that granites are relatively rich in Rb, Th, U,Pb, slightly enriched in the light rare earth elements La,Ce, and depleted in high field strength elements such as Nb, Ba and Sr, Ti; While the distribution model of REE is right oblique, which is relatively LREE enriched and HREE depleted, and the HREE curve is flat. Based on the results, these two kinds of granites are attributed to high differentiated metaluminous—weakly peraluminous high K calc alkaline series, which are the typical I type granites. The source materials might come from younger crustal felsic rocks with high K and normal water content, And the source material of felsic continental rocks of late Carboniferous granite unit is mixed with mantle derived basaltic components. The Middle Late Jurassic granitic magma maybe originated from the remelting or the partial remelting of Late Carboniferous granite, at least, it has similar magma source with that of the Late Carboniferous granite. The Late Carboniferous granite unit was formed in compression setting at the late syn collision stage of Central Asian Orogeny. The Middle Late Jurassic granite unit was formed in the extension environment setting, while the geotectonic background was changing from Mongolia—Ochotsk ocean system into the Paleo pacific tectonic dynamic systems.