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2026,72(1):1-8, DOI: 10.16509/j.georeview.2025.07.005
Abstract:
Based on principles of physics, by analyzing the formation and evolution of the initial Sun and Earth, the following insights have been derived as follows. (1) Around 4.7 Ga ago, hydrogen nuclei fused under high temperature and pressure, releasing immense energy, including thermal, light, and kinetic energy, leading to the formation of the star and the Sun. Between 4. 6 and 4. 2 Ga ago, nuclear fusion caused the Sun to undergo four flares, emitting highly energetic nuclear fission material into space. (2) The second flare from the Sun ejected materials that rapidly spun and entered the orbit of the primordial Earth, revolving around the original Sun, marking the first stage of Earth’s evolution, known as the cloud flight phase. Subsequently, Earth’s evolution progressed through several stages: accretion expansion phase, differentiation phase, continental nucleus formation phase, and the formation of primitive life phase. (3) During the accretion process and under the influence of gravity, the primordial Earth absorbed meteorites, ice clusters, and comet material, causing it to expand. Additionally, collisions, melting, and degassing occurred, further warming the primordial Earth. The process of matter aggregating towards the Earth’s core intensified particle collisions within the core, triggering nuclear decay, which accelerated internal warming of the primordial Earth, accumulating vast amounts of energy. Between 4. 5 and 4. 2 Ga ago, Earth was covered with molten lava, forming extensive magma oceans. (4) After 4. 2 Ga, the Sun no longer experienced intense flares, leading to a calm and cooling space around the Earth. Over time, Earth gradually cooled and stabilized. This cooling caused molten material to solidify and to crystallize, transforming the magma- covered Earth into a multi- layered structure with a core, mantle, lithosphere, and crust. (5) As temperatures dropped and molecular kinetic energy decreased, water vapor, CO2, hydrogen sulfide, methane, and other gases accumulated in Earth’s outer layers, eventually forming an atmosphere with a water cycle. Water vapor forms clouds, which cooled to create water droplets and precipitation. Around 4. 1 Ga ago, oceanic processes began, quickly forming Earth’s hydrosphere. (6) During the transition from magma spheres to water- covered spheres, lava continued to flow underground. Lighter elements usually have lower melting points and crystallize first into rock- forming minerals as they cooled. Meanwhile, volcanic eruptions on the ocean floor created volcanic islands of rocks. By about 4. 0 Ga ago, these rocks had coalesced into sizable blocks, forming the earliest continental nuclei. Due to the low thermal conductivity of continental lithosphere, it slowed the dissipation of Earth’s internal heat. Between 4. 0 and 3. 8 Ga ago, the continental nuclei grew rapidly, forming larger landmasses. (7) Comparing the early evolutionary processes of Mars and Earth shows that due to Mars being smaller and farther from the Sun, it generated and accumulated less energy during the accretion phase. Additionally, after accumulating some energy during its chaotic phase, Mars did not develop self- organizing mechanisms to preserve its internal energy. Therefore, Mars began to age quite early, say around 3. 0 Ga ago. In contrast, Earth has developed self- organizing mechanisms for internal material circulation over the past 3. 8 Ga, keeping the Earth system in an optimized stage of stable cohesion and balance development. Currently, there are no signs of aging on the Earth.
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HU Yimeng, YAN Jun, TAO Keqin, XU Linyu, LIU Qun
2026,72(1):9-32, DOI: 10.16509/j.georeview.2025.06.055
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The Tunxi Basin in southern Anhui Province, located in the eastern segment of the Jiangnan Orogenic Belt, exposes intermediate—acidic volcanic rocks of the Shiling Formation. The early- stage volcanism is dominated by rhyolitic tuff and trachyandesitic breccia, with zircon U- Pb ages of 150. 8 ± 2. 8 Ma and 156. 1 ± 2. 6 Ma respectively, indicating Late Jurassic volcanic rocks and the earliest stage of magmatic activity in the Mesozoic era in southern Anhui. Both types of rocks exhibit rich Si and K and low Mg characteristics, belonging to the high potassium calcium alkaline series. The distribution pattern of rare earth elements is right skewed, showing weak Eu negative anomalies, enriched whit large ion lithophile elements and light rare earth elements, and depleted in high field strength elements. At the same time, the rock mass has high Sr, Sr/Y, and (La/Yb)N values, which are characteristics of adakite. The range of εNd(t) values is -6. 36~-4. 92. The average formation temperatures of the two types of rocks obtained by zircon Ti thermometers are 763℃ and 795℃, respectively. Coarse andesite breccia is slightly higher, with a total average temperature of 785℃. Based on the geochemical characteristics of rocks and regional geological data, this article believes that the volcanic rocks of the Shiling Formation in the Tunxi Basin originated from a mixture of crustal and mantle magma. The crustal magma is a product of partial melting in the Neoproterozoic sedimentary rock source area, while the mantle magma originates from the mantle that has been replaced by material from subducting plates. It has a synchronous, homologous, and large- scale coupling relationship with the granodiorite in southern Anhui, and belongs to a volcanic intrusive complex system in a broad sense. Based on this, the Mesozoic magmatism in southern Anhui initiated with the Shiling Formation volcanics and minor intermediate—acidic intrusions, followed by large batholithic monzogranites and bimodal volcanics, and culminated with A- type K- feldspar granites. This tripartite evolution reflects the tectonic transition from low- angle subduction through slab rollback to renewed low- angle subduction of the Paleo- Pacific Plate.
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XU Bo, TONG Haikui, Liu Bei, LIU Lishuang
2026,72(1):33-49, DOI: 10.16509/j.georeview.2025.07.065
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The Proto- Tethys Ocean in the Eastern Kunlun region underwent an Early Paleozoic subduction—orogenic evolution. However, significant controversy remains regarding key geological processes such as subduction and collisional orogeny. A suite of Middle Silurian rapakivi granite and hornblende gabbro assemblages was discovered in the Qimantag area of the Eastern Kunlun. This study presents petrological, whole- rock geochemical, LA- MC- ICP- MS zircon U- Pb geochronological, and Sr—Nd—Pb isotopic analyses of these rocks. The zircon U- Pb ages of the rapakivi granite and hornblende gabbro are 430. 1 ± 1. 1 Ma and 430. 5 ± 1. 2 Ma, respectively.Whole- rock geochemical analyses show that the rapakivi granite has high K2O + Na2O content and TFeO/MgO ratios, but low MgO and CaO contents. It belongs to the metaluminous to weakly peraluminous granite series and the shoshonitic series. It is relatively enriched in light rare earth elements (LREEs) and large- ion lithophile elements (LILEs), but significantly depleted in high- field- strength elements (HFSEs), and exhibits a negative Eu anomaly. It has relatively high \[n(87Sr)/n(86Sr)\]i values (0. 709000~0. 723957) and negative εNd(t) values (-4. 82~-5. 89). The depleted mantle model age TDM2 ranges from 1559 to 1646 Ma. These characteristics classify it as A- type granite.The hornblende gabbro belongs to the low- K (tholeiitic) series. It is enriched in LILEs but depleted in HFSEs. It also exhibits high \[n(87Sr)/n(86Sr)\]i values (0. 709000~0. 723957), negative εNd(t) values (-4.82 to -5.89), and TDM2 ages of 1646~1559 Ma.The rapakivi granite and hornblende gabbro originated from distinct magma sources. The rapakivi granite primarily formed by partial melting of Paleoproterozoic felsic crust under low- pressure and high- temperature conditions. The magma source for the hornblende gabbro was the mantle wedge above the subducting slab, which had been metasomatized by subduction- derived fluids.Consequently, it is inferred that northward subduction of the Proto- Tethys Ocean initiated in the mid- Cambrian and persisted beyond 430 Ma. The Eastern Kunlun region was predominantly in a collisional orogenic stage from 428 Ma to 423 Ma, transitioning to an uplift stage from 423 Ma to 406 Ma. Around 430 Ma, the Eastern Kunlun region was in an extensional tectonic setting associated with subduction—rollback.
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YUN Xiaorui, FENG Jianyun, ZHENG Herong, ZHANG Ying, LUO Jun, ZENG Yan, LIAO Dawei, ZHANG Qiaoxun
2026,72(1):50-66, DOI: 10.16509/j.georeview.2025.03.045
Abstract:
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 and implemented by SINOPEC in 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 260. 7 ~ 250. 0 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 thrusting time of the granite rock set to between the middle—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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LI Jianwei, MI Kuifeng, WEI Zhengyu, ZHANG Baotao, HU Zhaoguo, MEI Zhenhua, SUN Feng
2026,72(1):67-81, DOI: 10.16509/j.georeview.2025.07.085
Abstract:
Numerous copper—polymetallic deposits are distributed in the border region between China and Mongolia. The Shiertolgai Cu—Mo deposit, located in Darhan Mumingan United Banner, Inner Mongolia, has undergone multiple exploration campaigns since its discovery, providing preliminary insights into the geological characteristics of the deposit. Methods: In this paper, based on detailed field geological work, systematic sampling of malachitized and unmineralized granodiorite from the Shiertaolegai mining area was carried out for analyses of major and trace elements, zircon U- Pb dating, and Hf isotopes.Results: The granodiorites exhibit high Si, Al, and K major element compositions, are relatively enriched in large ion lithophile elements (LILE) such as Rb, Ba, and K, and show depletions in high field strength elements (HFSE) including Nb, Ta, and Ti, indicating typical arc magmatic affinities. In addition, the zircon εHf(t) values of the granodiorites range from +4. 5 to +11. 3 and +7. 5 to +10. 6, with corresponding two- stage Hf model ages (TDM2) of 1028~589 Ma and 831~631 Ma, respectively, suggesting that the parent magmas were products of island arc magmatism. Conclusions: Based on regional tectonic studies, the authors propose that the Early Permian granites in the Mandula region were formed in a southward subduction setting of the Paleo- Asian Ocean.
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LIU Wenping, HE Yubo, LIU Chenglin, LIU Jia, XU Liang, WU Zhe, ZHONG Kesu, WU Qiuzi, LI Shuaizhi, LIU Ling
2026,72(1):82-94, DOI: 10.16509/j.georeview.2025.06.001
Abstract:
The deep shale gas resources in the Tiangongtang area of the Sichuan Basin are rich, but the exploration degree is relatively low. At the same time, the complex structural development conditions in this region seriously restrict the results of shale gas exploration and development.Methods: This study is based on the shale geological features and seismic data of the research area, using typical well data and balance profile restoration to investigate the fault development characteristics in the area and their effects on shale gas preservation.Results:The study shows that: ① In the Tiangongtang area, the Wufeng Formation — Longmaxi Formation primarily develops four levels of fractures, with level Ⅰ fractures mainly developed in the structural edge areas, level Ⅲ and Ⅳ fractures dominant in the north, and level Ⅱ, Ⅲ, and Ⅳ fractures primarily developed in the south. ② The formation of fractures in the Tiangong Tang area is mainly divided into three stages: during the late Yanshan period, SN compression formed fractures predominantly in the NW and NWW directions; in the early Himalayan period, NNE—SSW compression formed fractures mainly in the NW direction; since the mid- Himalayan period, NWW—SEE regional tectonic strike- slip stress has resulted in the formation of NE- dominant fractures. ③ The influence of fractures on shale gas retention is characterized by an increased gas content the further away one is from the fault; different scales of fractures have varying impacts on shale gas retention. When the distance from level Ⅰ fractures exceeds 5 km, level Ⅱ fractures are between 3~5 km, and level Ⅲ fractures exceed 2 km, the gas content exceeds 3.0 m3/t, indicating good shale gas retention conditions; level Ⅳ fractures have a minimal impact on shale gas retention.Conclusions: The development of faults varies significantly across different stages of burial evolution. During the burial stage, fault development is minimal, and its impact on shale gas preservation is negligible. During the slow uplift stage, large- scale fault development caused by compressive uplift severely damages preservation conditions. During the rapid uplift stage, fault development and reactivation further exacerbate shale gas loss.The study clarifies the shale gas preservation mechanism in the Tiangongtang area, providing theoretical support for further exploration and development.
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WANG Youpeng, LI Dewen, ZHENG Na, LI Xin, ZHAO Xiaolong, SU Shibing
2026,72(1):95-108, DOI: 10.16509/j.georeview.2025.07.021
Abstract:
During the process of migrating and accumulating toward the Earth's surface, fault- related hydrogen gas is influenced by both tectonic and non- tectonic factors. Based on the spatio—temporal variations of fault hydrogen volume fractions in the Wuhai Basin before and after the Yinchuan Ms 4.2 earthquake on February 20, 2025, and their relationship with regional tectonic features, the authors aim to clarify the significance of the coupling between the geological structures and activities of the Wuhai Basin and the physical/chemical properties of fault hydrogen in earthquake preparation and related fields.Methods: We adopted a research method combining qualitative and quantitative analyses to systematically analyze the annual variation characteristics of fault hydrogen volume fractions in the Wuhai Basin. The Pearson correlation analysis method was used to study the relationship between the changes in fault hydrogen volume fractions at the Molegou trace hydrogen observation point and air temperature as well as air pressure. The interference factors affecting the fault hydrogen volume fractions at the Molegou trace hydrogen observation point were excluded one by one using the elimination method.Results: ① Through the analysis of long- term observation records, data characteristics and abnormal factors from multiple stations, it is confirmed that before the Yinchuan Ms4.2 earthquake, the abnormal hydrogen volume fraction at the Moergou trace hydrogen observation site in the Wuhai Basin is a short- term pre- seismic anomaly. The trend of the abnormal change is that the hydrogen volume fraction value rises rapidly 4 hours before the earthquake the earthquake occurs it turns to decline 1 hour after the earthquake and it recovers to the background value 37 hours after the earthquake. Compared with the existing research cases, the trend of the abnormal change in hydrogen volume fraction is basically the same. The differences lie in the shorter imminent earthquake time and a much larger multiple of the abnormal value compared to the background value. ② Through the relationship between the regional tectonic pattern and short- term anomalies, it is believed that the abnormal increase in hydrogen volume fraction at the Moore Trench trace hydrogen observation point is related to specific tectonic positions. The Moore Trench trace hydrogen observation point is located on the hanging wall steep slope of a normal fault at the mountain—basin transition position in the northern segment of the west margin fault zone of Zhuozi Mountain. In the regional tectonic pattern, the area where the observation point is located has a certain tensile component, which is conducive to the rapid migration of a large amount of hydrogen enriched underground to the surface. ③ Geological structures and their activities (such as stress changes and ruptures), as well as the environment, can affect the migration and diffusion of fault hydrogen. Even within the same fault zone, the changes in fault hydrogen volume fraction will vary due to factors such as the tectonic state, stress changes and groundwater at different locations. Studying the coupling between geological structures and their activities and the physical and chemical properties of fault hydrogen is of great significance in the field of earthquake preparation and other aspects. Conclusions: These understandings provide a basis for the response of the abnormal fault hydrogen volume fraction in the Wuhai Basin to earthquakes and the relationship with tectonics. At the same time, they also have certain guiding significance for the layout of underground fluid observation stations.
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ZHENG Yilong, HE Jinrui, WU Jiayue, YU Zhaolin, RAN Shuhong, SUN Lin, AN Liwei, WANG Hongchu
2026,72(1):109-123, DOI: 10.16509/j.georeview.2025.06.065
Abstract:
Volcanic rocks of the Tiaojishan Formation are extensively distributed in the Yanshan Mountains and are crucial for understanding the large- scale teconic—magmatic activity during Yanshan movement. Although the age of the Tiaojishan Formation has been discussed by previous studies, most have focused on the eastern and western parts of the Yanshan Mountains. Consequently, the timing and petrogenesis of the Tiaojishan Formation in the central Yanshan, particularly the Sihai Basin, remain poorly constrained. A bimodal volcanic rock assemblage has been identified within the Tiaojishan Formation section at Shuiquanzi Village, Sihai Basin, central Yanshan Mountains. To obtain the ages and geological significance of the volcanic rocks of the Tiaojishan Formation, a geological section was measured through the formation, and systematic samples were collected for isotope geochronological analysis. Methods:Based on detailed field geological survey, Petrological and LA- ICP- MS zircon U- Pb geochronological analysis are employed to reveal the formation age and environment of the Tiaojishan Formation. Results:Vesiclar amygdaloidal basalt and andesitic basaltic sed- volcanic rocks were discovered for the first time within the Tiaojishan Formation in the Shuiquanzi Village, Sihai Basin, Central Yanshan Mountains. These mafic rocks, together with previously discovered rhyolite, constitute a bimodal volcanic suite, indicating deposition in a rift basin. Petrological and LA- ICP- MS zircon U- Pb geochronological analysis were conducted on andesite—basalt (sampled from the lower part ) and rhyolite volcanic breccia (sampled from the middle part). The results indicate that andesite—basalt crystallized at 159. 8±3. 7 Ma, and rhyolite volcanic breccia at 159. 0±1. 5 Ma. Combined with previous dating results, thses ages demonstrate that the Tiaojishan Formation in the Yanshan Mountains was primarily formed in the early Late Jurassic. These new ages fill a critical gap in the central Yanshan Mountains and align with the westward younging trend of Tiaojishan volcanism, extending from eastern Liaoning (170~153 Ma) to the northwestern Hebei (157~146 Ma). Conclusions: The Sihai Basin represents a NE—SW- trending rift basin formed during the early to middle Yanshan Movement (pre- 160 Ma). The bimodal volcanism and precise geochronology support a tectonic model where Paleo- Pacific slab subduction triggered westward- migrating mantle melting and crustal extension. These findings refine the spatiotemporal framework of Jurassic magmatism and enhance understanding of subduction- related lithospheric thinning in East Asia.
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HUANG Ming, LIU Lei, LIU Heng, ZHANG Yunfei, WEN Zhilin, HUANG Baoliang, ZHOU Weijian
2026,72(1):124-146, 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. 41 Ga to 1. 93 Ga) 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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ZHANG Chuangye, ZHOU Yueqiang, ZHANG Yunfei, WU Jun, ZHANG Shengwei, MEI Xiao, SUN Jiandong, WEN Zhilin, LIU Lei
2026,72(1):147-160, DOI: 10.16509/j.georeview.2025.07.015
Abstract:
The northeastern Hunan region within the Jiangnan Orogen hosts multiple large gold deposits, constituting a significant gold metallogenic belt in China with abundant gold resources. The Huangjindong Gold Deposit, a representative deposit in this area, features substantial reserves and high- grade mineralization. Gold mineralization in this district is closely associated with hydrothermal alteration, with common alteration minerals including sericite, siderite, and montmorillonite.As an efficient exploration technique, short wave infrared (SWIR) spectroscopy enables rapid identification of alteration mineral assemblages and their relative abundances, providing critical data support for alteration mineral mapping. Methods: Based on short wave infrared spectroscopy (SWIR), this study conducted hyperspectral scanning analyses on core samples from five drill holes in the ore vein of the Huangjindong Gold Deposit. By identifying the spectral characteristics of alteration minerals and analyzing the absorption peak position (POS2200) and crystallinity (IC value) of sericite, the spatial patterns of alteration minerals in the mining area were revealed.Results: More than 10 main alteration minerals were identified, with sericite being the dominant one. The λPOS2200 values of sericite mainly range from 2196 to 2210 nm, and the DSWIR- IC values range from 0.05 to 1.96. The mean λPOS2200 and DSWIR- IC values of sericite in alteration zones from different drill holes show a gradually increasing trend from west to east.Conclusions:Research reveals significant spatial distribution patterns of alteration minerals across drill holes from west to east: The λPOS2200 value of sericite progressively increases, indicating enhanced acidity of vein- forming hydrothermal fluids; concurrently, sericite illite crystallinity (DSWIR- IC) gradually decreases, demonstrating declining fluid temperatures and confirming west- to- east migration of ore- forming fluids along the vein. A temperature attenuation model based on DSWIR- IC was established, pinpointing the hydrothermal center. This validates the model's efficacy in tracing hydrothermal pathways and locating mineralization centers, providing critical guidance for mineral exploration. The study offers novel insights for interpreting alteration signatures at the Huangjindong gold deposit and delivers a scientific foundation for regional prospecting strategies.
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ZHANG Yaguang, XING Weiwei, MA Mengling, LI Qiang, YA Yu, LI Zeyang, XIA Xiang, GUO Shien
2026,72(1):161-176, DOI: 10.16509/j.georeview.2025.06.045
Abstract:
A set of intermediate and acid volcanic lava, volcanic tuff and volcanic breccia are developed in Yaleman Tousuquan Formation in the Eastern Tianshan Mountains. The magma evolved from neutral to acidic from early to late, and developed explosive facies, effusive facies and subvolcanic facies, characterized seven eruption rhythmic cycles. According to LA- ICP- MS zircon U- Pb isotopic dating, the rhyolite age of the Tousuquan Formation is 406. 0±3.0 Ma (MSWD=0. 35), and the age is early Devonian. Rock geochemistry shows that the volcanic rocks of Tousuquan formation have the characteristics of medium aluminum (13. 2%~18. 10%), rich in sodium and poor in potassium (K2O/Na2O=0. 10~0. 67), belonging to the high differentiation, low- to medium- K calc- alkaline series; The total amount of rare earth elements is relatively high (∑ REE=98. 7×10-6~214×10-6), LREE is enriched, HREE is depleted (LREE/HREE=3. 75~4. 58), Eu shows weak negative anomalies (δEu=0. 62～0. 92), large ion lithophile elements Rb, K, Ba are significantly enriched, and high field strength elements Nb, Ta and Ti are depleted. These geochemical characteristics exhibit signatures of mantle- derived remelted volcanic rocks that assimilated crustal materials during magma ascent, and indicate a continental margin arc tectonic setting related to subduction.
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ZHANG Jinlong, ZHANG Hongrui, PAN Zhilong, LUO Dike, XING Weiwei, LIU Silin, YU Long, JIA Pengfei, YANG Ning, LI Qiang
2026,72(1):177-198, DOI: 10.16509/j.georeview.2025.07.037
Abstract:
The West Congo Orogenic Belt is a part of Africa where the San Francisco Craton and Congo Craton converged and collided during the Pan African period. Its tectonic evolution has attracted the attention of scholars both domestically and internationally. Conducting research on the stratigraphy during this period is of great significance for exploring the tectonic evolution of the orogenic belt.Methods:This study selected the Inkisi Formation sandstone in the northwest of Angola in the foreland basin on the eastern edge of the orogenic belt as the research object, and conducted studies on chronology and petrology.Results: The minimum detrital zircon age in the Inkisi Formation sandstone is 588.0 ± 3. 0 Ma, and the discrimination diagram indicates that the sandstone was formed in a sedimentary basin under a collision background. The chemical alteration indices (CIA, CIW, PIA) of the Inkisi sandstone are 63. 34~73. 17, 70. 82~92. 29, and 65. 19~89. 56, the Sr/Ba values ranging from 0. 07 to 0. 24<0. 5.Conclusions: The petrological and chronological characteristics of the Inkisi sandstone indicate that it was formed in a basin related to collision environments in the context of active continental margins, and is a product of river sedimentary environments. Its source area was warm and humid ancient climate conditions, and the source rocks underwent low to moderate weathering. It is a response to the Pan African West Congo orogeny, and also suggests that the West Congo collisional orogeny continued during the Ediacaran—Early Cambrian period.
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ZHOU Zhi, REN Shoumai, ZHAO Weiyong, JIANG Zhenxue, BAO Shujing, WANG Shengjian
2026,72(1):199-211, DOI: 10.16509/j.georeview.2025.07.011
Abstract:
The Middle Jurassic strata in the Qaidam Basin exhibit favorable geological conditions for tight oil accumulation, but the main controlling factors for large- scale exploration and development remain unclear. Methods: Through analyses of organic geochemistry, reservoir physical properties, and homogenization temperature tests of fluid inclusions from core/cuttings of six wells (e.g., the Well Long- 2 and Chaiye- 1 in the Yuqia Sag, northern Qaidam Basin), this study investigates the characteristics of hydrocarbon source rocks and tight reservoirs in the Middle Jurassic Dameigou Formation, as well as the source—reservoir coupling relationships and their control on hydrocarbon accumulation.Result: The results indicate that the main hydrocarbon source rocks of the Dameigou Formation are primarily developed in the J2d7 segment. Tight delta—front distributary channel siltstone reservoirs interbedded with these source rocks exhibit excellent source—reservoir configurations. The J2d7 segment serves as the primary accumulation layer for tight oil in the Middle Jurassic of the Yuqia Sag. The reservoir densification occurred approximately 30 Ma ago, while hydrocarbon charging and accumulation took place about 3.29 Ma ago, representing a single- phase charging and one- stage accumulation process. Conclusion: The thermal maturity of the source rocks controls the distribution of Middle Jurassic tight oil in the northern Qaidam Basin. Late Jurassic—Cretaceous compressional inversion and intense uplift during the late Neogene led to significantly lower thermal evolution degrees of Middle Jurassic source rocks in the Yuqia Sag compared to other hydrocarbon- generating sags in northern Qaidam. Prospective exploration areas for Middle Jurassic tight oil include the Qianxi region, Hongshan Sag, and southwestern Yuqia Sag in the northern Qaidam Basin.
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MA Fenling, WU Zhichun, JIANG Shuming, LI Hongda, GUO Fusheng, LI Hualiang, LIU Pinghua, LI Bin, JIN Wenlong
2026,72(1):212-228, 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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CHEN Xifeng, SHI Junfa, TANG Jinrong, ZHANG Weibo, YANG Zhongxi, ZHANG Zhenfang
2026,72(1):229-243, DOI: 10.16509/j.georeview.2025.03.055
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 overseas 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 overseas. 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 overseas over the past 20 years. The results show that: ① The net increases in reserves and resources of copper, nickel, cobalt and lithium in overseas over 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. ② Porphyry 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. ③ The Circum-Pacific copper-polymetallic metallogenic belt, Southeast Asian nickel metallogenic belt, Central African copper-cobalt metallogenic belt 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. ④ Large international mining companies have the most of the increases in reserves and resources of exploration progress of copper, nickel, cobalt and lithium in overseas over the past 20 years. ⑤ Some newly-emerging countries of new energy minerals are formed over 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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WANG Meng, WANG Bolin, HE Jiaxin
2026,72(1):244-252, DOI: 10.16509/j.georeview.2025.06.022
Abstract:
This paper utilizes a natural experiment provided by global geoparks to identify the impact of tourism resources on economic growth.Methods: This paper constructs a difference- in- differences model.Results: Regression analyses based on panel data of 284 cities in China from 2003 to 2020 show that global geoparks drive economic growth. Cities with global geoparks have an average increase of 9.7 percentage points in the growth rate of per- unit- area light brightness compared to cities without global geoparks. This result remains robust in a series of analyses, including adding control variables, selecting a subsample, and changing time lag. Heterogeneity analyses reveal that the positive effect of global geoparks on economic growth is stronger in cities without tourism brand certifications, but there is no difference between cities with different transportation infrastructures. The mechanism by which global geoparks promote economic growth is to drive tourism development.Conclusions: The conclusions of this paper provide insights for policymakers to develop tourism resources.
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XIONG Canjuan, YANG Ruidong, GAO Junbo, CHEN Jiyan, JIANG Yuan, LI Zhi, PENG Rou, GAO Chuanqian, PANG Yuyu
2026,72(1):253-268, 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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DUAN Zhuang, GONG Jingjing, LI Lei, LI Zhenhuan, WANG Zengxiang, YANG Jianzhou, LI Yong, HU Shuqi, TANG Shixin, GONG Qiuli, XIE Changli, GAO Jianwong, FU Yangang
2026,72(1):269-278, DOI: 10.16509/j.georeview.2025.04.021
Abstract:
Scientific drilling cores are valuable physical materials for earth science research. They directly reflect the deep structure, material composition, and geological history of the Earth. These cores hold considerable importance and unique value for research in multiple disciplines including geology, geophysics, geochemistry, materials science, and information science. This study aims to explore and practice methods for low- loss chemical composition analysis and physical property measurement of scientific drilling cores to achieve the protection and efficient utilization of precious scientific drilling core resources. The paper proposes a scientific plan for sample layout and collection, then elaborates on the sampling process for physical property measurements, conducting wave speed, density, magnetic, and electrical measurements on different specifications of samples. For the chemical composition analysis of cores, a low- loss testing strategy is proposed, including ensuring single- analysis dosage, selectively analyzing trace elements, and handling special cases. Finally, the importance of sample repositioning and preservation of surplus samples is emphasized. The "low- loss chemical composition analysis and physical property measurement" method for scientific drilling cores proposed in this paper has been practiced during project implementation and has achieved preliminary application results. It holds significant importance for promoting the protection and efficient use of scientific drilling cores.
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REN Liping, XU Lianfeng, DU Kaiyuan, LI Ruiqiang, SHI Lin, WANG Haiyong, WANG Zifan, MA Yuheng, LIU Linke
2026,72(1):279-294, DOI: 10.16509/j.georeview.2025.07.041
Abstract:
To address the prevalent issues in mine ecological restoration, such as monotonous techniques, insufficient geological foundation, neglect of geological condition differences, and a gap in cultural integration, this study focuses on the abandoned mine at Pugongshan in Xixian County, Henan. It aims to explore an integrated approach that combines ecological restoration, cultural preservation, and sustainable economic development.Methods: The project innovatively adopts a geological perspective, systematically constructing a comprehensive restoration system. This system integrates geological restoration technologies (including geological landscape reconstruction, land reconstruction and stabilization, land substrate improvement, and water resource reconstruction) with natural restoration techniques (such as vegetation ecological restoration and landscape ecological maintenance). It further incorporates cultural elements and tourism space development techniques, forming a "geology + nature + culture + tourism" four- in- one integrated 4.0 ecological restoration model.Results:The implementation results demonstrate that this model successfully restored the mine's ecological environment, effectively resolved geological safety hazards, while simultaneously creating distinctive cultural landscapes and realizing tourism industry development. It formed a three- in- one integration of ecological, cultural, and tourism functions. Its core value lies not only in eliminating environmental problems but also in creating long- term economic benefits, powerfully promoting regional sustainable development.Conclusions: This model provides replicable and scalable successful experience and a demonstration case for systematic, multifunctional ecological restoration of similar abandoned mines domestically, delivering significant comprehensive ecological, economic, and social benefits.
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2026,72(1):295-304, DOI: 10.16509/j.georeview.2025.07.017
Abstract:
The Deep-time Digital Earth (DDE) initiative represents a pioneering undertaking in the realm of scientific research, spearheaded by Chinese scientists and endorsed by the International Union of Geological Sciences, a global authority in the field of geosciences. The primary objective of the DDE project is the establishment of an unparalleled, interconnected digital repository, encompassing the intricate evolutionary trajectory of the Earth. Utilizing state-of-the-art information technology and data science methodologies, the project seamlessly integrates the temporal span of geological history with contemporary earth observation data. This integration fosters the creation of a comprehensive, dynamic and multifaceted earth system model, offering a unique perspective on the evolution of our planet. Paleogeographic maps are important spatial-temporal visualization tools for revealing geological and environmental resource issues such as geomorphological evolution processes, plate movements, and changes in species distribution, and for constructing a deep-time digital earth. Since the 1970s, foreign scholars have constructed paleogeographic reconstruction models using substantial geophysical data, primarily paleomagnetic, geochronological, and paleontological fossil data. Following two decades of research, a significant number of paleogeographic maps have been made available through online platforms such as EarthByte and the Gplates Web Portal. These maps encompass a wide range of information, including superimposed topographic maps, geological maps, elevation data, magnetic anomalies, lithology, and other elemental details. Presently, numerous domestic online geological information application systems incorporate the superimposed display of elements such as samples, occurrences, fossils, and mineral points on contemporary maps. However, most systems lack the visualization function of online paleogeographic maps, thus preventing them from expressing the chronological information of geological data from a temporal dimension. The author of this paper aims to construct a paleogeographic map visualization web application (Single Page Application, SPA) system that can be expeditiously deployed using a technical route based entirely on free and open source frameworks. The application's interface is designed to facilitate the switching between different paleogeographic reconstruction models, thereby enabling the display of geological elements such as rocks and paleontological fossils, which possess both spatial attributes and geochronological attributes. The Vue component plays a pivotal role in the separation of front-end module components from data, thereby facilitating seamless integration with the front end of a Web GIS system for data transmission and functional module integration. This integration process is particularly noteworthy in terms of its rapid deployment within a B/S-based GIS framework.
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LIANG Xingjiang, CHEN Luming, ZHANG Zhigang, ZHENG Chaogang, ZHAO Dan, LI Yiman, LU Nanxin, ZHANG Hongmei
2026,72(1):305-313, DOI: 10.16509/j.georeview.2025.07.095
Abstract:
Terrestrial in situ cosmogenic nuclide（TCN）10Be exposure dating method is currently one of the most successful dating methods for glacier geomorphology, and this technology has made significant contributions to global glacier geomorphological dating. During the dating process, granite samples are usually selected for dating. However, granite exposed over millennia is subject to weathering, which reduces the concentration of cosmogenic nuclide Be- 10 on the surface, leading to an underestimation of the exposure age of the landform. Thus, we aim to quantify the erosion rate of granite over millennial timescales to improve the accuracy of cosmogenic nuclide exposure dating. This application is crucial for understanding evolution of glacial landforms. This study focuses on the palaeo- Daocheng ice cap, where the Be- 10 exposure dating technique was applied to determine the surface exposure ages of granites with varying degrees of weathering. Six granite samples sites and twelve Be- 10 age samples were processed. By combining the weathering thickness difference, the erosion rates of granite samples were estimated. The results from six granite sample sites and twelve Be- 10 age samples indicate that the erosion rate of granite in the palaeo- Daocheng ice cap area ranges from 1.3 mm/ka to 3.6 mm/ka over the past 30 ka. This study provides a reliable reference for estimating sample erosion rates in cosmogenic nuclide exposure dating.
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ZHANG Zechen, ZHANG Sujiang, LIU Jingjing, XIAO Chun, GAO Pengxin
2026,72(1):7201314-7201320, DOI: 10.16509/j.georeview.2025.07.035
Abstract:
Samples constitute a crucial component of physical geological archives. China's implementation of regional geochemical survey projects has generated massive sample collections. Statistical data indicate that the country has accumulated 9. 94 million Type I and II geochemical samples, preserved in national and provincial repositories. Secondary development and utilization of these samples could facilitate the discovery of new mineral exploration clues and support green low-carbon development. However, current sample service effectiveness remains suboptimal, primarily due to the absence of standardized information collection protocols, unified publication mechanisms, and an integrated information management platform.This paper proposes an information management and service system for physical geological sample archives, structured through four hierarchical components: infrastructure layer, data resource layer, functional layer, and user interface layer. The designed system enables sample information storage, updating, and service utilization for multi-tier user groups. Its implementation aims to enhance data sharing among repository institutions at various administrative levels, improve informational management of sample resources, and promote high-quality development of physical geological archives. This system is expected to provide substantial support for China's new round of strategic mineral exploration initiatives while contributing to the advancement of sustainable resource management practices.
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2026,72(1):7201320-7201321, DOI:
Abstract:
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2026,72(1):7201322-7201328, DOI: 10.16509/j.georeview.2025.06.025
Abstract:
In 1934, the Ministry of Industry of the National Government and the Ministry of Education jointly with the national geological survey and research institution, successfully held the first large- scale national mining and metallurgy geology joint exhibition in modern China in Tianjin National Peiyang Institute of Technology, for the purpose of observing and discussing, spreading new knowledge and revitalizing industry. The first mining and metallurgy exhibition with various treasures and talents and big momentum, had attracted wide attention from people of all walks of life, and was of great benefit to the people in promoting intellectual knowledge, academic contention, scientific and technological progress and industrial revitalization. Based on the original documents and materials such as archives and newspapers, this paper systematically investigated the origin, preparation process, exhibition pomp and social impact of the first mining exhibition, and deeply explored the important position of mining and metallurgy exhibition in modern China's social propaganda and mobilization, ideological enlightenment and patriotic education, saving the country by mining industry and the cherished wish of national prosperity and people.
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2026,72(1):2026010001-2026010001, DOI: 10.16509/j.georeview.2026.01.045
Abstract:
The glaciology developed in the West during the 19th century and foucsed on the study of Glaciers.This kind of knowledge was then introduced to China in 1854 through missionary publications. At the time, several Chinese translations were proposed, among which“冰川” (bingchuan) was the popular one. In the early 20th century, the Japanese derived the Japanese term “冰河” (binghe)，which entered China and shocked the existing translation terms. After 1911, most geological publications and terminology standardization tended to adopt the Chinese term“冰河”. However, starting in the 1920s, the Chinese geologists such as Li Siguang conducted pioneering research on glaciers in China, the term “冰川” gradually gained acceptance around Chinese Geologists. The new Committee for the Unification of Scientific Terminology made “冰川” the standard term in 1954 and the competition between the “binghe” and “bingchuan” finally ended. This conflict over termms shows how Chinese geological terms changed. It reflects how the Geology developed in China, which from translating foreign knowledge to finally becoming a mature and independent discipline.
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JIA Long, FAN Xianke, ZHANG Haiqi, ZHU Likuan, WANG Hongjie, TIAN Mingjun, YU Deshui, WANG Shoujing
2026,72(1):2026010002-2026010002, DOI: 10.16509/j.georeview.2026.01.065
Abstract:
High- purity quartz ore, as a new mineral species, serves as an important raw material for the development of modern high- tech industries. The discovery of the Longquanping high- purity quartz deposit in the North Qinling belt represents a significant breakthrough in China’s exploration of pegmatite- type high- purity quartz deposits, but its genetic mechanism remains unclear. Methods: Based on detailed studies of ore deposit geological characteristics and petrography, columbite—tantalite and muscovite from the No. 10 high- purity quartz pegmatite in the Longquanping deposit were selected to carry out in- situ U- Pb, Rb- Sr, and 40Ar- 39Ar isotope geochronological research, aiming to constrain the formation age, metallogenic geological setting, and post- ore metamorphic modification history of the high- purity quartz deposit.Results: The results show that the U- Pb age of columbite—tantalite from the No. 10 pegmatite vein at the Longquanping deposit is 422.1±2.8 Ma, which is essentially consistent with the peak mineralization period (430~410 Ma) of rare- metal pegmatites in the region. These pegmatites were likely formed in a post- collisional extensional setting. The 40Ar- 39Ar and in- situ Rb- Sr ages of muscovite are 330.5±3.2 Ma and 306.0±15.0Ma, respectively, which are significantly later than the columbite—tantalite U- Pb age(422.1 Ma) but consistent with the previously reported metamorphic thermal event of 320~300 Ma in the North Qinling region. This indicates that the 40Ar- 39Ar and Rb- Sr isotopic systems in the pegmatite were reset during a later metamorphic event, thereby recording the metamorphic modification history experienced by the high- purity quartz pegmatite after its formation.Conclusions: Combined with petrographic characteristics of quartz, it is demonstrated that the Longquanping high- purity quartz pegmatite vein is similar to the pegmatite- type high- purity quartz deposits in the world, such as the Spruce Pine deposit in the United States and the Tysfjord deposit in Norway. After the formation of pegmatites, these deposits underwent multiple stages of metamorphic modification, leading to deformation and dynamic recrystallization of quartz, which facilitated the formation of high- purity quartz. Therefore, post- formation metamorphic modification may be a critical factor for the formation of pegmatite- type high- purity quartz deposits.
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LI Weike, YANG Xinbiao, HU Shaobing, LIU Junping, ZHANG Hu, ZHAO Jiangtai, YAN Haibao, LU Xiaoping, YANG Houbing, ZOU Fei
2026,72(1):2026010003-2026010003, DOI: 10.16509/j.georeview.2026.01.022
Abstract:
During the Late Jurassic, the Chuxiong Basin in central Yunnan served as a typical inland lake, where a thick succession of red clastic sedimentary rocks—commonly known as “red beds”—was deposited. Based on a 1:50000- scale regional geological survey, a unique fossil assemblage comprising dinosaurs, turtles, fish, bivalves, and plants was discovered for the first time within the Upper Jurassic Tuodian Formation in the Shuangbai area of the Chuxiong Basin.Results: The fossils are well- preserved and occur in situ. The host lithology consists of purplish- red fine- grained lithic sandstone and silty mudstone. Research has identified the dinosaur remains as theropods, the turtle fossils as Xinjiangaspideretes oshansis, the fish as Lepidotes, the bivalves as Plicatounio, and the plant fossils as Amentotaxus. Additionally, fossil fragments of other unidentified vertebrates were also recovered. This significant discovery not only enhances our understanding of Late Jurassic biodiversity in the Chuxiong Basin but also fills a critical gap in the vertebrate fossil record of the basin’s Late Jurassic strata. Considering the composition of the fossil assemblage and associated sedimentary structures such as ripple marks, the depositional environment is interpreted as a relatively stable low energy lacustrine water setting.Conclusions: The synchronous preservation of diverse organisms suggests that during the Late Jurassic, the lake underwent severe contraction, a dramatic reduction in water extent, a hot and arid climate, and a general deterioration of the ecological conditions.
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LI Yonggang, GAO Junbo, LUO Bangliang, HE Shanli, WANG Wenjie, LIU Ling, FU Yong, SHI Qingpeng, LUO Sheng
2026,72(1):2026010004-2026010004, DOI: 10.16509/j.georeview.2026.01.015
Abstract:
Barite is a national emerging strategic mineral resource. The Dahebian super- large barite deposit in Tianzhu, Guizhou, the largest barite resource base in China, has long seen its deep exploration hampered by insufficient understanding of the structural controls. Under the New Round of Strategic Action for Mineral Exploration Breakthroughs, the research team, through intensified investigation and comprehensive study, redefined the late- stage ore- disrupting effect of the ore- controlling fault F1 and revealed the critical control of siliceous rock thickness on orebody sedimentation. Based on these new insights, the cumulative newly identified barite resources in the hanging wall and footwall of the F1 fault within the Dahebian barite ore cluster have reached 174 Mt. For the first time, a blind barite orebody was discovered in the footwall of the F1 fault, significantly expanding the exploration potential and achieving a major breakthrough in barite prospecting. Simultaneously, it is predicted that the resource potential of this ore cluster exceeds 500 Mt, which will play a crucial supporting role in maintaining and enhancing the strategic position of barite resources in southeastern Guizhou.
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2026,72(1):2026010005-2026010005, DOI: 10.16509/j.georeview.2026.01.055
Abstract:
以相关史料为基础，梳理新中国地质工作体系的构建过程。地质工作是经济会发展的重要基础和先行，新中国成立后，积极探索并建立全新的地质工作体系，促进了地质事业的大发展，为新中国的工业化建设提供了坚实保障，为中华民族实现独立自主发展、走向繁荣富强奠定了坚实的物质基础。
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WANG Donghui, WU Liang, LI Dezong, XIAO Changyuan, ZHANG Hao, YU Yifan, LI Zhiwei, LIU Yong, LI Ming, HE Song
2026,72(1):2026010006-2026010006, DOI: 10.16509/j.georeview.2026.01.032
Abstract:
This study intends to investigate the occurrence states of rare earth elements (REEs) in the paleo- terrigenous sedimentary rare earth deposits at the bottom of the Xuanwei Formation in the Shuizhu area, northeastern Yunnan, within the contiguous region of Sichuan, Yunnan and Guizhou. The research is expected to provide crucial clues and a scientific basis for mineral exploration and comprehensive resource utilization of the same type of sedimentary rare earth deposits in the study area and across China.Methods: In this paper, a variety of rock and mineral testing techniques including basic chemical analysis, X- ray diffraction (XRD) analysis, scanning electron microscopy (SEM) analysis, and rare earth leaching experiments were employed to conduct an in- depth mineralogical study on the paleo- continental sedimentary rare earth deposits in the Lianfeng area of Yongshan County, Zhaotong City, Yunnan Province.Results: The analysis results show that the average grade of total rare earth oxides (TREO) ranges from 0.12% to 0.21%, with the maximum content of a single sample reaching 0.23%. The ratio of light rare earths to heavy rare earths is between 1.55 and 2.88, indicating a light- rare- earth- dominated characteristic, where light rare earths account for 61%~73% of the total rare earth content. Mineralogically, the ore is dominated by clay minerals with a total content of approximately 75%, among which kaolinite is the predominant component (45%), followed by montmorillonite (36%) and chlorite (19%). The contents of other minerals are trace, and independent rare earth minerals are extremely scarce. Leaching tests and measurements reveal that the ion- adsorbed phase accounts for only 0.94%–3.86% of the total rare earths, suggesting a relatively low content of ion- exchangeable rare earths. The results indicate that the rare earth elements in the samples are likely to occur as rare- earth- enriched nanomineral particles hosted within clay minerals such as kaolinite.
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ZHANG Shiqi, WANG Jianke, HE Chengguang, ZHAI Wenjian, HUANG Danfeng
2026,72(1):2026010007-2026010007, DOI: 10.16509/j.georeview.2026.01.002
Abstract:
The Shesuo ophiolitic mélange is located in the middle—east segment of the Shiquanhe—Nam Lake (Nam Co) ophiolitic mélange zone, Xizang (Tibet). In order to clarify the petrogenesis, sedimentary environment and understand its geological significance of the siliceous rocks in the Shesuo ophilitic mélange. Furthermore, attempt to explore the tectonic attributes of the Shiquanhe—Nam Lake ophiolitic mélange zone.Methods: In this paper, research on the siliceous rocks from the Shesuo ophiolitic mélange, including field work, petrology, as well as major- and trace- element analysis. Moreover, the petrogenesis and sedimentary environments of these siliceous rocks have also been discusssed.Results: The Shesuo siliceous rocks are exposed on the top of basalt, is purplish red or red color. The Shesuo siliceous rocks consist of three types: rich radiolarian siliceous rocks, interbedded radiolarian siliceous rocks, and rare radiolarian siliceous rocks. The geochemical characteristics of the rich radiolarian siliceous rocks reveal that they were biogenic siliceous rocks deposited at the continental magin which more farther from mainland in the subduction and reduction stage of the oceanic plate. interbedded radiolarian siliceous rock show that they were biogenic siliceous rock affected by the mid- oceanic ridge marginal hydrothermal plume, and were deposited in the oceanic basin. Rare radiolarian siliceous rocks reveal that it was hydrothermal siliceous rocks mey be deposited in the marginal area of the mid- oceanic ridge, far from the central rift valley. These siliceous rocks should have been deposited in different stages during the late Jurassic to early Cretaceous with the expansion of the oceanic crust. The subsequent geological structural activities such as the shortening of the Lhasa terrane, and the Qinghai—Xizang (Tibet) Plateau continuous uplift lead to the Shesuo siliceous rocks exposure within a limited area at present.Conclusions: Based on the research result of the Shiquanhe—Nam Lake ophiolitic mélange zone, in this paper, we speculated that the Shesuo Meso- Tethy Ocean which located at the middle—east segment of the Shiquanhe—Nam Lake Meso- Tethys Ocean was already has complete mid- oceanic ridge—oceanic basin—continental margin system, and the oceanic basin was mature and expansive relatively . It may be indicated that the Shiquanhe—Nam Lake Meso- Tethys Ocean was an independent and new fromed ocean that emerged slightly later than the Bangongco—Nujiang Meso- Tethys Ocean.
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2026,72(1):2026010008-2026010008, DOI: 10.16509/j.georeview.2026.01.025
Abstract:
The current resource tax collection method in China has basically changed from "specific duty" to "ad valorem". However, the resource tax in the formula for calculating the mineral deposit grade index in the current relevant courses, specifications and applications in China is calculated in raw ore, and the unit is yuan/t. Therefore, these formulas consider that the resource tax is still calculated based on the specific duty. Therefore, in the current application processes of ore deposit industrial indicator demonstration, mining right evaluation, etc., it is necessary to calculate the resource tax based on the raw ore through the revenue and other indicators. However, applying the resource tax calculated based on the raw ore through back calculation in these formulas will lead to distortion of the calculation results. Therefore, the author derives a new formula for calculating ore deposit grade indicators. The new formula incorporates the resource tax rate calculated based on the ad valorem resource tax, without the need for back calculation of the resource tax based on the raw ore. Finally, through the comparison and analysis of these formulas in the application of ore deposit grade indicator calculation in Yaogangxian tungsten deposit, it is shown that there are problems with the current formula for calculating ore deposit grade indicators, and it is proven that the new formula derived by the author is simple, reasonable, and widely applicable. Therefore, it is suggested that the new formula derived by the author be adopted in future applications of ore deposit industrial indicator demonstration, mining right evaluation.
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LI Yupeng, ZHANG Litao, YANG Yongchun, ZHANG Jing, CHEN Yongyao, ZHAO Haijun
2026,72(1):2026010009-2026010009, DOI: 10.16509/j.georeview.2026.01.075
Abstract:
研究区大地构造位于中亚造山带南缘的北山造山带北带，明水岩浆弧Ⅲ级构造单元（图1a），地理位置位于甘新蒙交汇部位，成矿区带归属于古亚洲成矿域，马庄山—狼娃山—黑鹰山铁、金、钨、锡成矿带，区域矿产资源丰富，成矿地质条件良好，目前已发现的矿产主要有金、铁、钨、铬、萤石、铜、锰、脉石英等，以金、铁、钨矿最具优势。新一轮找矿突破战略行动实施以来，该区域已发现岩浆热液型钨钼、萤石共伴生大中小型矿床几十余处（小独山西钨矿、聚源钨矿、白峡尼山钨矿、珍石峰钨矿、小白石头钨钼矿、七一山萤石及钨多金属矿、小狐狸山萤石矿、国庆钨矿、鹰嘴红山钨矿、玉山钨及萤石矿、咸水井钨多金属矿、华窑山钨多金属矿、斜沟钼矿），显示了较好成矿前景。该区域已发现矿床多为中小型矿床，区域找矿一直未有大的突破，近年来，甘肃省地矿局四勘院在该区开展地质勘查工作时，在白山泉一带新发现了萤石及钨多金属矿化线索，通过三个年度的地质勘查工作，新发现大型矽卡岩型萤石及钨多金属矿床一处，取得了突破性找矿成果，对该区同类型萤石及钨多金属矿寻找提供了找矿方向，对北山成矿带找矿工作具有重要的借鉴意义。
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GOU Fugang, GONG Xulong, CHENG Yu
2026,72(1):2026010010-2026010010, DOI: 10.16509/j.georeview.2026.01.012
Abstract:
The dry wet characteristics of aquitards have environmental indicative significance and are key parameters affecting soil engineering geological characteristics. Therefore, studying the response mechanisms of soil moisture characteristics to paleoclimate and paleoenvironment since the Late Pleistocene is of significant importance.Methods: 2787 water content samples were collected and tested for liquid limit, plastic limit, and particle size in the Yangtze River Estuary area. Based on the drawn water content geological profile combined with dating data, grain size data, lithology, color, water content etc., perform paleoclimate and paleoenvironment inversion since the Late Pleistocene.Results: The results indicate that the lithology of the Qp31 aquitard is mainly silty clay, with a color of yellow gray, which is a coastal sedimentary facies with an average water content of 28.4% and high spatial variability in the Yangtze River Estuary area. The lithology of the first hard soil layer in Qp32 is mainly composed of silty clay, with a grayish yellow color. It is deposited in the river floodplain facies, with an average water content of 28.5%. The Qh aquitards can be classified as silty clay, clay (in small amounts), and soft soil, all of which are reduced in color except for the surface soil. Among them, soft soil has high water content characteristics, which are greater than 32%.Conclusions: The water content of the first hard soil layer shows an increasing trend with depth, indicating that the climate gradually becomes cooler and drier from bottom to top. The Qh aquitard has a high water content, which is mainly related to the warm and humid climate. Part of the middle and deep Qh aquitards have low water content, even below 25%, which is related to cold events such as 8.2 ka, 5.5 ka, 4.2 ka, and 2.8 ka. The water content of Qh deep aquitards are significantly negatively correlated with burial depth and distance from the coastline, indicating that the newer the sedimentary age of the soil and the shorter the distance from the coastline, the higher the water content of the soil.
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WU Xiaotian, LI Xi, ZHU Guangyou, YANG Zhe, FU Shiyu, XU Kai, LI Jiyuan, ZHAO Yuhao
2026,72(1):2026010011-2026010011, DOI: 10.16509/j.georeview.2026.01.041
Abstract:
Tight sandstone reservoirs, characterized by low porosity, low permeability, strong heterogeneity, and difficulty in "sweet spot" prediction, represent a critical focus and challenge in current unconventional oil and gas exploration and development research. As one of the most important filling minerals in tight sandstone reservoirs, chlorite profoundly influences reservoir properties and hydrocarbon-bearing potential. Clarifying the enrichment characteristics of chlorite and its regulatory mechanisms on reservoir properties and hydrocarbon occurrence capacity will provide crucial insights for the precise prediction of hydrocarbon-bearing "sweet spots" in tight sandstones. We systematically analyzes the mechanisms and controlling factors of chlorite’s impact on the hydrocarbon-bearing potential of tight sandstone reservoirs, focusing on its occurrence modes, genetic mechanisms, and coupling relationships with diagenetic evolution. Research indicates that chlorite primarily exists in reservoirs in three forms: grain-coating, pore-lining, and pore-filling. Among these, grain-coating chlorite forms through the combined effects of precursor clay mineral transformation, detrital material replacement, and pore fluid precipitation. Pore-lining chlorite originates from the transformation of sedimentary clay coatings, dissolution and recrystallization of Fe-Mg-rich materials, or mixed transformation and direct crystallization processes. Pore-filling chlorite precipitates from Fe-Mg-rich pore waters or forms via the transformation of smectite and illite. Chlorite formed during different diagenetic stages exerts dual effects on reservoirs: positive effects include enhancing rock compressive strength, inhibiting pressure dissolution, promoting dissolution processes, and suppressing quartz overgrowth; negative effects involve pore-throat blockage and permeability reduction. Chlorite formation spans the entire sedimentary-diagenetic evolution process, and its influence on reservoir hydrocarbon potential exhibits spatiotemporal variability and multi-factor synergy. Core controlling factors include chlorite occurrence, thickness, continuity, and interactions with diagenetic stages. Hydrocarbons primarily occur as films adsorbed onto chlorite surfaces and within its intercrystalline pores, or as isolated/aggregated particles. Minerals with larger specific surface areas exhibit higher adsorption potential energy for hydrocarbons. Chlorite from different diagenetic stages possesses varying adsorption capacities, with pore-lining chlorite’s intercrystalline pores demonstrating the strongest hydrocarbon adsorption capability. "Sweet spot" reservoirs typically feature chlorite with moderate thickness and complete continuity, often distributed in high-energy sedimentary environments and avoiding zones of thick cementation. Moderate development of pore-lining chlorite provides favorable space for hydrocarbon charging and storage. We provide a comprehensive mineralogical and petrological basis for the "sweet spot" prediction of tight sandstone hydrocarbon reservoirs, which is of great significance for deepening the understanding of hydrocarbon enrichment mechanisms in tight reservoirs and optimizing exploration and development strategies.
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JIANG Wenlong, GUO Wenjian, CUI Zhenyu, HAN Yang, XIANG Wei, WANG Tao, LIU Hailei, WANG Xueyong
2026,72(1):2026010012-2026010012, DOI: 10.16509/j.georeview.2026.01.021
Abstract:
Objective: The Penyijingxi Sag, one of the three hydrocarbon rich sags in the Western Depression of the Junggar Basin. has recently achieved significant breakthroughs in deep—ultra-deep natural gas exploration. However, research on the origin and genetic mechanisms of these deep—ultra-deep natural gas accumulations remains limited.Methods: This study systematically investigates the genetic types and source contributions of natural gas through comparative analysis of gas composition, carbon isotopes, and light hydrocarbon data with typical genetic end-members. Results: The results demonstrate that the genesis of deep—ultra-deep natural gas in the Penyijingxi Sag can be divided into three types: ① Typical humic type gas, mainly from the Carboniferous, characterized by deep burial, high maturity (dry gas) and localized distribution; ② Typical sapropelic type gas mainly derived from the Permian Fengcheng Formation source rocks, exhibiting widespread distribution, relatively low maturity (condensate oil and gas); ③ Mixed natural gas, which is mainly mixed from Permian Fengcheng Formation and Carboniferous source rocks. Then the proportion of mixed source gas was analyzed by Chemometrics. Based on these findings, a "dual-source hydrocarbon charging and paleo-uplift accumulation" accumulation model was established for deep—ultra-deep natural gas reservoirs in the Penyijingxi sag and its periphery.Conclusions: This research provides critical theoretical support for advancing hydrocarbon exploration in deep to ultra-deep strata of Western Depression.
Volume 72,2026 Issue 1
Scolarly discussion
Scientific review
Reserch progress
Correspondence·Reference·News report·Introduction to new book
Publish online-I
Volume 72,2026 Issue 1
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Risk Assessment and Source Apportionment of Heavy Metals in Farmland Soils of the Longchuan River Basin, Central Yunnan
HUANG Jiazhong, LI Suoming, TU Chunlin, JIANG Xin, ZENG Liang, WANG Bingjun, SONG Lin
Abstract:
Objectives：This study examines the distribution of heavy metals in the agricultural soil of the Longchuan River basin, situated in central Yunnan. Methods：A concentrated farmland area in Chuxiong City, Yunnan Province was selected as the study site, and topsoil samples (0–20 cm) were systematically collected. The analysis encompassed evaluations of soil pH and the concentrations of eight heavy metals: arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn). To assess the risk of heavy metal pollution, the study employed soil pollution risk screening values for agricultural land as a reference point, utilizing both the Nemerow Comprehensive Pollution Index and the Potential Ecological Risk Index methodologies. These approaches facilitated the assessment of pollution risk, identification of primary sources of heavy metal contaminants. Results：The overall soil environmental quality was good, with an average pH of 6.78 (neutral). Except for localized Cd exceedances along the Longchuan River banks, heavy metal pollution risk was generally low. Compared to Yunnan soil background values, As, Pb, Hg, and Zn were depleted; Cr, Ni, and Cu were similar; Cd was relatively enriched. The average Nemerow composite pollution index was 0.616, and the average comprehensive potential ecological risk index was 32.54, indicating overall low heavy metal hazard but notable local ecological risk from Cd. Conclusions：PMF analysis revealed five principal sources: pedogenic parent material weathering (natural source, 29.65%), atmospheric deposition (23.33%), a mixed source of agricultural activities and riverine sedimentation (17.75%), direct agricultural activities (17.54%), and a mineralized stratum source associated with mining activities (11.74%). The results underscore the combined influence of natural geology and human activities on soil heavy metal accumulation in this high-background area.
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Comparative Study of Sedimentary Bauxite Deposits in the Yunnan-Guizhou-Guangxi Region and Its Prospecting Guidance Significance
Qin Feng, Wu Xiangke, Li Liji, Meng Xianglun
Abstract:
Bauxite is an advantageous mineral resource in the Guangxi region. The exploration work for alluvial bauxite in the area has reached a relatively high level, leaving limited potential for new discoveries. In contrast, the exploration of sedimentary bauxite is still in its initial stage, and its metallogenic rules and ore-seeking directions urgently require further systematic research. Based on the collection and comparison of data on sedimentary bauxite in the Yunnan-Guizhou region, and combined with recent exploration progress, this paper systematically discusses the metallogenic geological background, host strata, characteristics of aluminum-bearing rock series, orebody geological features, and ore quality of sedimentary bauxite in western Guangxi, aiming to provide guidance and reference for the exploration of sedimentary bauxite in the Guangxi region. Comparative research results show that the Heshan Formation (P3h) of the Upper Permian System in western Guangxi is widely distributed, with well-developed aluminum-bearing rock series, indicating good ore-seeking prospects and being the main target horizon for exploring sedimentary bauxite. The area has conditions to form thick funnel-shaped orebodies. Strengthening research on karst paleotopography and combining it with appropriate geophysical exploration methods can help discover such thick orebodies. However, due to inconspicuous leaching effects, the bauxite here is mainly in the form of bean-oolitic and dense ores, with relatively scarce earthy ores and lower ore grades.
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The Century-Long Debate about the Term Glacier：Translation, Dissemination, and Standardization of “Glacier” in China
Abstract:
The concept of “glacier”, after being defined within Western geology, was introduced to China in 1854. The late Qing period saw varied translations, among which 冰川 (bingchuan)emerged. Following the First Sino-Japanese War, the Japanese translated term 冰河 (binghe) was imported, sparking a century-long contest between the two. Early Republican China leaned toward 冰河, but pioneering research by Li Siguang in 1921 significantly bolstered the academic standing of 冰川. The terminological competition was conclusively resolved in 1954, when China’s Committee for Scientific Terminology Unification formally established 冰川 as the standard term. This process not only standardized a key geological term but also reflected the dynamic interplay of transnational and indigenous forces in shaping modern Chinese science.
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Discussion on the existing problems in the current formula for calculating ore deposit grade indicators and the exploration of a new formula
Abstract:
The current resource tax collection method in China has basically changed from "specific duty" to "ad valorem". However, the resource tax in the formula for calculating the mineral deposit grade index in the current relevant courses, specifications and applications in China is calculated in raw ore, and the unit is yuan/t. Therefore, these formulas consider that the resource tax is still calculated based on the specific duty. Therefore, in the current application processes of ore deposit industrial indicator demonstration, mining right evaluation, etc., it is necessary to calculate the resource tax based on the raw ore through the revenue and other indicators. However, applying the resource tax calculated based on the raw ore through back calculation in these formulas will lead to distortion of the calculation results. Therefore, the author derives a new formula for calculating ore deposit grade indicators. The new formula incorporates the resource tax rate calculated based on the ad valorem resource tax, without the need for back calculation of the resource tax based on the raw ore. Finally, through the comparison and analysis of these formulas in the application of ore deposit grade indicator calculation in Yaogangxian tungsten mine, it is shown that there are problems with the current formula for calculating ore deposit grade indicators, and it is proven that the new formula derived by the author is simple, reasonable, and widely applicable. Therefore, it is suggested that the new formula derived by the author be adopted in future applications of ore deposit industrial indicator demonstration, mining right evaluation.
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Isotopic Dating of Columbite-Tantalite and Muscovite from the North Qinling Pegmatite-Type High-Purity Quartz Deposit and Geological Implicationsu: Case Study of the Longquanping No. 10 Vein
Jia Long), Fan Xianke), Zhang Haiqi, Zhu Likuan), Wang Hongjie), Tian Mingjun, Yu Deshui), Wang Shoujing)
Abstract:
Objectives: High-purity quartz ore, as a new mineral species, serves as an important raw material for the development of modern high-tech industries. The discovery of the Longquanping high-purity quartz deposit in the North Qinling belt represents a significant breakthrough in China""s exploration of pegmatite-type high-purity quartz deposits, but its genetic mechanism remains unclear. Methods: Based on detailed studies of ore deposit geological characteristics and petrography, columbite-tantalite and muscovite from the No. 10 high-purity quartz pegmatite in the Longquanping deposit were selected to carry out in-situ U-Pb, Rb-Sr, and 40Ar-39Ar isotope geochronology research, aiming to constrain the formation age, metallogenic geological setting, and post-ore metamorphic modification history of the high-purity quartz deposit. Results: The result shows that the U-Pb age of columbite-tantalite from the No. 10 pegmatite vein at the Longquanping deposit is 422.1±2.8 Ma, formed during the Late Silurian, representing the formation age of the high-purity quartz pegmatite. It indicates that the high-purity quartz pegmatites in the Longquanping deposit were mineralized during the Late Silurian to Early Devonian epochs (420-400 Ma), which is consistent with the peak mineralization period of rare metal pegmatites in this area (430-410 Ma), formed in a post-collision extensional geological setting. The 40Ar-39Ar and in-situ Rb-Sr ages of muscovite are 330.5±3.2 Ma and 306.0±15.0 Ma, respectively, consistent with the metamorphic thermal event around 320-300 Ma in the North Qinling region previously identified. This indicates that the 40Ar-39Ar and Rb-Sr isotopic systems in the pegmatite were reset during a later metamorphic event, thereby recording the metamorphic modification history experienced by the high-purity quartz pegmatite after its formation. Conclusions: Combined with petrographic characteristics of quartz, it is demonstrated that the Longquanping high-purity quartz pegmatite vein is similar to the pegmatite-type high-purity quartz deposits in the world, such as the Spruce Pine deposit in the United States and the Tysfjord deposit in Norway. After the formation of pegmatites, these deposits underwent multiple stages of metamorphic modification, leading to deformation and dynamic recrystallization of quartz, which facilitated the formation of high-purity quartz. Therefore, post-formation metamorphic modification may be a critical factor for the formation of pegmatite-type high-purity quartz deposits.
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New breakthrough in Cambrian barite exploration, Qiandongnan
LI Yonggang, Gao Junbo, Luo Bangliang, He Shanli, Wang Wenjie, Liu Ling, Fu Yong, Shi Qingpeng, Luo Shen
Abstract:
Barite is a national emerging strategic mineral resource. The Dahebian super-large barite deposit in Tianzhu, Guizhou, the largest barite resource base in China, has long seen its deep exploration hampered by insufficient understanding of the structural controls. Under the New Round of Strategic Action for Mineral Exploration Breakthroughs, the research team, through intensified investigation and comprehensive study, redefined the late-stage ore-disrupting effect of the ore-controlling fault F1 and revealed the critical control of siliceous rock thickness on orebody sedimentation. Based on these new insights, the cumulative newly identified barite resources in the hanging wall and footwall of the F1 fault within the Dahebian barite ore cluster have reached 174 Mt. For the first time, a blind barite orebody was discovered in the footwall of the F1 fault, significantly expanding the exploration potential and achieving a major breakthrough in barite prospecting. Simultaneously, it is predicted that the resource potential of this ore cluster exceeds 500 million tons, which will play a crucial supporting role in maintaining and enhancing the strategic position of barite resources in southeastern Guizhou.
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The Construction of the Geological Work System in New China
Abstract:
按专家意见删除。
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Moisture content characteristics of aquitards since the Late Pleistocene in the Yangtze River estuary and its environmental indication significance
goufugang, Gong Xulong, Cheng YU
Abstract:
Objectives: The dry wet characteristics of aquitards have environmental indicative significance and are key parameters affecting soil engineering geological characteristics. Therefore, studying the response mechanisms of soil moisture characteristics to paleoclimate and paleoenvironment since the Late Pleistocene is of significant importance. Methods: 2787 water content samples were collected and tested for liquid limit, plastic limit, and particle size. Based on the drawn water content geological profile combined with dating data, grain size data, lithology, color, water content, etc., perform paleoclimate and paleoenvironment inversion since the Late Pleistocene. Results: The results indicate that the lithology of the Qp31 aquitard is mainly silty clay, with a color of yellow gray, which is a coastal sedimentary facies with an average water content of 28.4% and high spatial variability. The lithology of the first hard soil layer in Qp32 is mainly composed of silty clay, with a grayish yellow color. It is deposited in the river floodplain facies, with an average water content of 28.5%. The Qh aquitards can be classified as silty clay, clay (in small amounts), and soft soil, all of which are reduced in color except for the surface soil. Among them, soft soil has high water content characteristics, which are greater than 32%. Conclusions: The water content of the first hard soil layer shows an increasing trend with depth, indicating that the climate gradually becomes cooler and drier from bottom to top. The Qh aquitard has a high water content, which is mainly related to the warm and humid climate. Part of the middle and deep Qh aquitards have low water content, even below 25%, which is related to cold events such as 8.2ka, 5.5ka, 4.2ka, and 2.8ka. The water content of Qh deep aquitards are significantly negatively correlated with burial depth and distance from the coastline, indicating that the newer the sedimentary age of the soil and the shorter the distance from the coastline, the higher the water content of the soil.
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Geochemical characteristics and sedimentary environment of Shesuo siliceous rocks in the middle-east segment of the Shiquanhe-Nam Co ophiolite mélange zone,Tibet
ZHANG Shiqi), WANG Jianke), HE Chengguang), ZHI Wenjian), HUANG Danfeng)
Abstract:
Objectives: The Shesuo ophiolitic mélange is located in the middle-east segment of the Shiquanhe-Nam Co ophiolitic mélange zone. In order to clarify the petrogenesis, sedimentary environment and understand its geological significance of the siliceous rocks in the Shesuo ophilitic mélange. Furthermore, attempt to explore the tectonic attributes of the Shiquanhe-Nam Co ophiolitic mélange zone. Methods: In this paper, research on the siliceous rocks from the Shesuo ophiolitic mélange, including field work, petrology, as well as major-and trace-element analysis. Moreover, the petrogenesis and sedimentary environments of these siliceous rocks have also been analyzed. Results: The Shesuo siliceous rocks are exposed on the top of basalt, is purplish red or red color. The Shesuo siliceous rocks consist of three types: rich radiolarian siliceous rocks, interbedded radiolarian siliceous rocks, and rare radiolarian siliceous rocks. The geochemical characteristics of the rich radiolarian siliceous rocks reveal that they were biogenic siliceous rocks deposited at the continental magin which more farther from mainland in the subduction and reduction stage of the oceanic plate. interbedded radiolarian siliceous rock show that they were biogenic siliceous rock affected by the mid-oceanic ridge marginal hydrothermal plume, and were deposited in the oceanic basin. Rare radiolarian siliceous rocks reveal that it was hydrothermal siliceous rocks mey be deposited in the marginal area of the mid-oceanic ridge, far from the central rift valley. These siliceous rocks should have been deposited in different stages during the late Jurassic to early Cretaceous with the expansion of the oceanic crust. The subsequent geological structural activities such as the shortening of the Lhasa terrane, and the Qinghai-Tibet Plateau continuous uplift lead to the Shesuo siliceous rocks exposure within a limited area at present. Conclusions: Based on the research result of the Shiquanhe-Nam Co ophiolitic mélange zone, in this paper, we speculated that the Shesuo Meso-Tethy Ocean which located at the middle-east segment of the Shiquanhe-Nam Co Meso-Tethys Ocean was already has complete mid-oceanic ridge-oceanic basin-continental margin system, and the oceanic basin was mature and expansive relatively . It may be indicated that the Shiquanhe-Nam Co Meso-Tethys Ocean was an independent and new fromed ocean that emerged slightly later than the Bangongco-Nujiang Meso-Tethys Ocean.
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Study on the Occurrence State of Rare Earth Elements at the Bottom of the Xuanwei Formation in the Shuizhu Area, Yongshan, Yunnan
wangdonghui, lidezong, Xiao Changyuan, zhanghao, Yu Yifan, Li Zhiwei, Liu Yong, Li Ming, He Song
Abstract:
This study employs various petrological and mineralogical testing techniques—including basic chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and rare earth leaching experiments—to conduct a detailed mineralogical investigation of the Paleogene continental sedimentary-type rare earth deposit in the Lianfeng area of Yongshan, Zhaotong, Yunnan Province. Analytical results indicate that the average total rare earth oxide (TREO) grade ranges from 0.12% to 0.21%, with the highest single sample reaching 0.23%. The light-to-heavy rare earth ratio falls between 1.55 and 2.88, indicating a predominance of light rare earth elements (LREE), which account for 61%–73% of the total rare earth content. The mineral composition is dominated by clay minerals, accounting for approximately 75% of the total, primarily kaolinite (45%), followed by montmorillonite (36%) and chlorite (19%). Other minerals are present in minor amounts, with very few independent rare earth minerals identified. Leaching tests and measurements reveal that the ion-adsorbed phase constitutes only 0.94%–3.86% of the total rare earth content, indicating a relatively low proportion of rare earth elements in ionic form. The research findings suggest that the rare earth elements in the samples may be hosted within nano-sized, rare-earth-enriched mineral particles embedded in clay minerals such as kaolinite.
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Discovery of Fossils in the Late Jurassic Tuodian Formation of the Chuxiong Basin, Central Yunnan and Its Paleoenvironmental Significance
Abstract:
Objectives: Southeast Yunnan is located on the southwestern margin of the Youjiang Basin. There are many controversies regarding the tectonic evolution of the Late Paleozoic. Whether there are relics of ocean basins in the Southeast Yunnan - border area of Yunnan and Guangxi between the Yangtze Block and the Cathaysian Block from the Paleozoic to the Triassic, or whether it was merely a rift environment, is one of the important issues in the study of the evolutionary history of the South China Plate. Results:Through 1:50,000 field geological surveys, a set of marine basic volcanic rocks intercalated with intermediate-acidic volcanic rocks and radiolarian cherts has been identified in the Huajia area of Funing. The volcanic rocks develop pillow structures and spherulitic structures, forming a typical marine volcanic rock assemblage. Zircon U-Pb dating of the dense basalt yields an age of 260.3±2.4 Ma (n=9, MSWD=0.34), indicating that the volcanic rocks formed in the Late Permian. Geochemical characteristics show that the volcanic rocks belong to the high-titanium tholeiitic basalt series, with a slightly right-inclined rare earth element distribution pattern, enriched in light rare earth elements (LREE) and incompatible elements such as Rb, Ba, and Th, which are similar to the characteristics of typical ocean island basalts (OIB), and their tectonic setting was formed in an extensional tectonic environment. Combined with the field occurrence and rock assemblage characteristics, it is considered to be a set of ocean island - seamount assemblages. Conclusions:Based on the comprehensive analysis of the geochemical characteristics of regional volcanic rocks in Yunnan and Guangxi, paleomagnetism, sponge spicule cherts, and sedimentary characteristics of radiolarian cherts, this paper holds that the Southeast Yunnan area of the Youjiang Basin had developed into a mature and complex multi-island ocean basin system during the Middle - Late Permian. This further provides new volcanic rock evidence for reconstructing the geological evolution process of the Late Paleozoic ocean basin in Southeast Yunnan, and confirms the existence of an ocean basin system in Southeast Yunnan during the Middle - Late Permian.
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Key issues of basin-range coupling and their application in the study of Mount Langshan and the Cretaceous basins on both sides
Abstract:
Based on the key points of basin-range coupling summarized from previous studies, we established a geometric model of mountain erosion and basin filling sequence. We also conducted a logical analysis of the method popular over the past two decades—using detrital zircon age peak correlation to determine the provenance of clastic rocks—and pointed out its source-sink mismatch problems. Taking Mount Langshan and the Early Cretaceous clastic rocks on both sides as examples, we discussed the related basin-range coupling issues: First, Google Earth images identified antecedent rivers in Mount Langshan, with incised meanders as typical representatives. This reveals that Mount Langshan was uplifted later, negating the previous view that it served as the source area for the Early Cretaceous sedimentation. Subsequently, detailed field investigations were carried out in the Celaomiao Depression, an eastern marginal depression of the Bayingebi Basins. Paleocurrents of the Lower Cretaceous clastic rocks were restored using directional sedimentary structures such as foreset laminae, showing a dominant north-to-south direction. This indicates that the provenance of the Celaomiao Depression during the Early Cretaceous was to its north, while Mount Langshan had not yet uplifted. Outcrops of the Bayingebi Formation clastic rocks and the overlying Suhongtu Formation basalts discovered at the southern foot of Mount Langshan further confirm that the Bayingebi Basins extended far southeastward across Mount Langshan. Q-F-L ternary diagrams of sandstones from the Bayingebi Formation show that the provenance on the northwest side of the basin was a volcanic arc, and the Bayingebi Basins were forearc basins. Early planar X-shear joints in the outcropping rocks of the Bayingebi Formation were used to restore the paleostress field, indicating a NW—SE direction for the maximum principal stress. The authors also found ophiolitic mélanges in a series of imbricated thrust sheets at the southern foot of Mount Langshan. Among these, the minimum age of basalts and metamorphic diabases (representing oceanic crust components) is 88.2Ma, proving that Mount Langshan are the collision boundary between the North China Craton and the Central Asian Orogenic Belt, with the collision time constrained to the end of the Cretaceous. Detailed field investigations were conducted on outcrops of red conglomerates and sandstones of the Lower Cretaceous Lisangou Formation at the southern foot of Mount Langshan. Paleocurrents restored from foreset laminations show a dominant southeastward direction. The presence of abundant laminated quartzite pebbles in the red conglomerates indicates that the provenance of this red bed sequence was the uplift zone to its northwest, where the main outcrops were characterized by quartzite, consistent with the lithology of quartzite thrust sheets at the southern foot of Mount Langshan. The red conglomerate layer should have been deposited to the southeast of the forebulge during its formation. Planar X-shear joints and spaced cleavage structures developed in the conglomerates of the Lisangou Formation were used to restore the paleostress field, revealing a NW—SE direction for the maximum principal stress. Later section X-conjugate shear fractures and small thrust faults in the conglomerates of the Bayingebi Formation at the southern foot of Mount Langshan were also used for paleostress restoration, with the maximum principal stress still in the NW—SE direction. This indicates that the stress direction of the rock layers remained basically unchanged during the progressive deformation from early to late stages. The subsequent deformation structures of the Early Cretaceous sedimentary layers on both sides of Mount Langshan occurred under a unified stress regime, reflecting the deformation history of the Ordos Block subducting and colliding northwestward. This study provides new data and ideas for research on the tectonic evolution of the Central Asian Orogenic Belt and the North China Craton. Basin-range coupling is a comprehensive research strategy based on various practical materials, but each analytical step must comply with basic geological principles without logical errors. It is hopeful that this attempt will serve as a good exploration example for basin-range coupling research.
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Geological characteristics and genetic analysis of the Gangou Pb-Zn deposit in Xunyang basin,South Qinling Mountains
zhangzhen, GaoYongBao, Wei LiYong, Meng WuYi, Wu HuanHuan, Jia Bin, Tang MingFeng, Yang BenZhao, Tian YingTian
Abstract:
The Zhen’an-Xunyang is a Late Paleozoic fault-depressed basin in the southern Qinling region. A large number of lead-zinc deposits are distributed along the arcuate fault zone at the southern margin of the Xunyang Basin, with existing reserves exceeding 200 Mt. These deposits are mainly hosted in the silty phyllite of the Meiziya Formation and Shuanghezhen Formation of the Silurian, and the ore bodies are predominantly stratified or banded, having undergone synsedimentary deposition and tectonic modification. In this study, the Gangou lead-zinc deposit located in the central part of the metallogenic belt was selected as the research object. Based on detailed field investigations, mineral fabric and geochemical analyses were conducted on the Gangou lead-zinc deposit. The main minerals in the Gangou lead-zinc deposit are predominantly sphalerite, with secondary minerals including galena, pyrite, and chalcopyrite, while the gangue minerals are mainly quartz and sericite. On this basis, fluid inclusion H-O and in-situ S-Pb isotope tests were carried out on quartz and metal sulfides from the main mineralization stages. Hydrogen and oxygen isotopes indicate that the ore-forming fluids are characterized by a mixture of magmatic fluids and organic waters, with the addition of meteoric water. The δ34S values of metal sulfides such as sphalerite and pyrite in the ore range from 3.43‰ to 6.46‰, suggesting that sulfur is primarily derived from depth and has mixed with sulfur in the strata. Lead isotopes indicate that the lead has a crust-mantle mixing characteristic, and the lead-zinc deposits in the area share similar geological and geochemical features. It is preliminarily concluded that the lead-zinc deposits within the Zhenxun Basin exhibit typical characteristics of sedimentary exhalative (SEDEX) lead-zinc deposits. Although later tectonic activities have modified the strata and deposits, their sedimentary features have been largely preserved, and the original host horizons and characteristics of the deposits remain consistent with their primary features.
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Zircon U–Pb age, geochemistry, and tectonic implication of the Shaquanzinan ilmenite Gabbros in Eastern Tianshan
TAN Zhixiong), JIA Hongxu, SONG Zhihao, Masumeh SARGAZI
Abstract:
Objectives: This study focuses on the newly identified Shaquanzinan ilmenite-bearing gabbroic pluton, hosting a medium-sized ilmenite deposit to south of the Aqikuduke-Shaquanzi fault zone within the Central Tianshan Block. The objectives are to elucidate the mantle source tectonic setting, and ilmenite metallogenic processes in Eastern Tianshan. Methods: Zircon U-Pb dating, whole-rock major and trace element geochemistry, and Sr-Nd isotopic analyses were conducted in this study. Results: (1) Zircon U-Pb dating reveals the Shaquanzinan ilmenite-bearing gabbro emplaced at 486.6 ± 2 Ma, demonstrating it being the oldest known ilmenite-dominated V-Ti magnetite deposit in the Tianshan region. (2) Geochemically, the rocks are characterized by low SiO2 (38.16–46.90 wt%), and MgO (4.67–7.04 wt%) contents, as well as low Mg# (39–55, average 46) values, coupled with elevated Al2O3 (12.30–19.37 wt%) and total alkalis (K2O + Na2O = 2.47–5.01 wt%), consistent with an alkaline series affinity. Chondrite-normalized rare earth element (REE) patterns display significant light REE enrichment and heavy REE depletion, with variable positive Eu anomalies (Eu* = 0.96–1.77). Primitive mantle-normalized trace element diagrams exhibit pronounced enrichment in Nb, Ta, Ti, Ba, Pb, and Sr, and depletion in Zr, Hf, Th, and U. Both major and trace elements compositions share an oceanic island basalt (OIB)-like features. (3) The ilmenite-bearing gabbros have depleted Sr-Nd isotopic compositions, with initial n(??Sr)/ n(??Sr) initial ratios of 0.7042–0.7045 and εNd(t) values of +0.76 to +1.07, indicating their derivation from a depleted mantle source. Conclusions: Comprehensive investigations reveal that this gabbroic pluton was formed in a back-arc extensional setting, induced by the retreat of the Junggar oceanic plate during the Late Cambrian. The parental magma was derived from low-degree (5%–10%) partial melting of a garnet lherzolite mantle source, followed by cumulate and fractional crystallization. The enrichment of ilmenite and minor magnetite as ore-forming minerals is attributed to the residual concentration of Fe-Ti components in the early-stage melt, coupled with melt segregation and crystallization under elevated oxygen fugacity conditions during the late magmatic stage.
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Error Correction in Clastic Sediment Grain Size Analysis: A Comprehensive Comparison and Application Based on Stereomicroscopy Image Analysis
LIU Junling, YIN Taiju, Feng Wenjie, LIU Shengqian, WANG Shixun
Abstract:
Objectives: Grain size analysis of clastic sediments is a crucial technical method for studying their depositional processes and environments. Existing methods such as sieving, laser diffraction, and thin-section image analysis suffer from differences in principles and limitations in applicability, hindering the accurate characterization of grain sizes across different size fractions and genetic types. To address this issue, this study proposes a stereomicroscopy image analysis method and systematically compares the applicability of various methods in clastic rock grain size analysis, with a focus on evaluating systematic biases and developing a correction model for thin-section measurement data. Methods: Four narrow-size-range standard samples of quartz sand (G1: 63–125 μm, G2: 125–250 μm, G3: 250–500 μm, G4: 500–2000 μm) were prepared for parallel experiments. The stereomicroscopy image analysis method, based on Greenough dual-light-path three-dimensional imaging, was introduced to avoid the two-dimensional "sectioning effect," and the Feret geometric mean diameter (Dgeo) was adopted as a morphology-compatible grain size characterization parameter. Results:(1) The average grain sizes measured by stereomicroscopy image analysis and laser diffraction are highly correlated, but the latter exhibits significant systematic underestimation (approximately 31%–37%); (2) Thin-section image analysis yields systematically smaller average grain sizes (32.28%–44.37%) due to the sectioning effect and particle irregularity. Numerical simulations quantitatively reveal that the errors originate from the sectioning effect (8.80%–21.84%) and morphological effect (22.53%–35.57%); (3) A correction model for thin-section image analysis average grain size is established based on the correction coefficient *k* (1.47–1.80); (4) Statistical analysis determines that the minimum sample size for stereomicroscopy image analysis is 300 particles, confirming its suitability for accurate analysis of coarse-grained (medium sand to fine gravel), micro-area (laminae), and trace (<1 g) samples. Conclusions: Stereomicroscopy image analysis demonstrates significant advantages in accuracy, measurement range, and sample requirements, making it an ideal method for characterizing irregularly shaped clastic particles, especially coarse-grained and trace samples. This study provides a scientific basis for selecting grain size analysis methods for different sample types and establishes a theoretical foundation for correcting thin-section grain size data and geological interpretation.
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A Brief Discussion on the "Marine M Carbonate Factory"
SHEN Yuefeng, LU Hui, HUANG Zhenhui, JIN Jinjian, ZHANG Cong, QI Fanyu, SUN Shuo, HU Bo
Abstract:
The concept of the "Marine M Carbonate Factory" was proposed nearly two decades ago, yet its definition remains ambiguous, its controlling factors highly variable, and the origin of its primary components—micrites complex and debated. Various terminologies—such as the “mud mound” factories, the “automicrite” factories, the “microbialite” factories, and the “cold-seep” carbonate factories—overlap and intertwine, further complicating the classification. To advance research on carbonate factories, there is an urgent need to clarify their conceptual framework, standardize their classification, and synthesize their controlling factors and genetic origins. Based on extensive literature review, this paper systematically examines the proposal, evolution, and unresolved issues surrounding the Marine “M” Carbonate Factory concept. It summarizes the possible sources of carbonate micrite within marine carbonate factories and proposes a refined classification scheme. The “Marine M Carbonate Factory” is categorized into two major groups with six subclasses: (1) Euphotic Zone Microbialite Factories (further divided into skeletal microbialite factories and non-skeletal microbialite factories); (2) Mesophotic-/Aphotic Zone Mud Mound Factories (subdivided into automicritic mud mound factories and allomicritic mud mound factories). The automicritic mud mound factories can be further classified into: a) Heterotrophic automicritic carbonate factory; b) Cold-seep automicritic carbonate factory; c) Hydrothermal automicritic carbonate factory. Finally, this paper offers perspectives on the transitions between different categories within the M carbonate factories in marine settings and their transitions with other carbonate factories, as well as on the microbial loop and sponge loop within M carbonate factories during the microbial-metazoan transition period.
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Zhao Lei, Xiang Kunpeng, Peng Chenglong, Zhang Deming
Abstract:
This study reports newly discovered marine reptile fossils in the Longshetiao area, Ceheng County, northwest margin of the Nanpanjiang Basin. The fossil fragments are exposed as scattered pieces within the clastic limestone belong to the upper part of the Loulou Formation, Early Triassic, which demonstrating typical heterochthonous burial. And the Neogondolella jubata and Chiosella timorensis were collected from argillaceous limestone overlying the fossil-bearing strata, indicates these fossils belong to the Spathian substage of the Olenician stage, contemporaneous with those marine reptile fossils found at Zhebao and Wangmo area. Based on the fossil burial patterns and the geological evidence that the clastic limestone and slip-deformation were widespread in the upper part of Loulou Formation around the Laizishan anticline, this study proposes that the transportation and burial of Early Triassic marine reptile in the northwest margin of the Nanpanjiang Basin may be closely related to storm events triggered by earthquakes. This finding holds significant implications for deciphering fossil burial mechanisms and reconstructing paleogeographic contexts during the late Early Triassic.
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Overall Concept of Urban Geological Work in the New Development Stage
CHENG Guanghua, YANG Yang, WANG Rui, YU Peng, FU Jiani
Abstract:
With the rapid advancement of urbanization in China, urban development has entered a new stage. The Central Urban Work Conference held in 2025 clearly stated that we should build a modern people-centered city that is innovative, livable, beautiful, resilient, civilized and smart, and firmly hold the bottom line of urban safety. China's urban geological work has undergone four phases: single-factor surveys before 2003; three-dimensional geological surveys and comprehensive geological surveys from 2003 to 2018; multi-factor urban geological surveys since 2018; and urban geological safety risk surveys and assessments since 2022. Each phase has played a vital role in supporting urban planning and construction according to the development priorities of its time. However, under the current stage of high-quality urban development, new challenges related to survey precision, data reliability, and long-term sustainability have emerged, revealing limitations in the existing urban geological framework. In response, this study proposes a novel “four-in-one” urban geological work system for the new development stage, integrating urban geological demand objectives, operational systems, technical methods and standard frameworks, and data and information platforms. Additionally, it provides recommendations regarding institutional arrangements and policy mechanisms to promote the advancement of urban geological work toward greater systematization, comprehensiveness, and sustainability.
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Study on the sedimentary structural evolution of the Jinxi fold belt: Evidence from carbonate cluster isotopes
WANG Ce, ZOU YU, YOU DONG HUA, LIU DONG NA, ZHOU RUN, JIANG TAO, DONG QING WEI
Abstract:
The Jinxi Flexural Belt represents an important tectonic unit in the central North China Craton, whose sedimentary and structural evolution is closely linked to the overall tectonic development of the craton. Based on carbonate core samples obtained from the Daning and Yonggu wells, this study applies clumped isotope (Δ??) thermometry to quantitatively constrain the burial temperatures and diagenetic fluid characteristics, and to explore the coupling mechanisms between stratigraphic hiatuses and the region’s thermal evolution. The clumped isotope data reveal that matrix carbonates (average 42.27 °C) record integrated signals of low-temperature sedimentation and subsequent burial heating, whereas calcite veins (average 106.2 °C) reflect later exogenic fluid activities. High-temperature solid-state reordering models indicate that several samples experienced multiple thermal events from the Jurassic to the Quaternary, during which burial temperatures rose to approximately 110 °C. Integrating clumped isotope evidence with regional thermal history and diagenetic evolution, this study reconstructs the thermal burial history of the Jinxi Flexural Belt and constrains the maximum burial temperatures to 110 °C in Daning and 100 °C in Yonggu. Furthermore, the calcite veins in the Daning Majiagou Formation and Yonggu Cambrian strata are interpreted to have formed during Yanshanian and Himalayan hydrothermal events, respectively. These findings suggest that intense tectonic deformation during these periods led to large-scale folding and thrust faulting, establishing the regional flexural structural framework of the Jinxi Belt.
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Water-Rich Mechanism and Exploitable Resource Quantity of Paleogene System Calcareous Conglomerate in Xinzhuang Water Source Area, Laiwu, Jinan City
wanguangqiang, Kang Fengxin, Wang Jinxiao, Li Jialong, Cui Yang, Xing Liting, Pang Wei, Xi Hongfeng, Qin Peng, Sui Haibo, Zhu Qingli
Abstract:
It has traditionally been considered that the Paleogene clastic rocks in the Luzhong Mountain Area have no water supply significance. Taking the Xinzhuang water source in Laiwu, Jinan as an example, this study explored the water-rich mechanism of the water-bearing rock formation of the gray conglomerate in the Zhujiagou Formation of the Paleogene in the water source through hydrogeological surveys, drilling, group well interference pumping tests, dynamic monitoring and other work. The compensatory dewatering method was used to constrain the exploitable resource quantity of the water-bearing rock formation, and further, a Dupuit confined steady well flow analytical model was established based on MATLAB software. Through parameter optimization and other measures, the dynamic response characteristics of the total water level drawdown of the test well group under different exploitation schemes during the dry season were revealed, and the allowable exploitable resource quantity of each well was determined. The results show that: under the combined action of fault water conduction and the water resistance of mud and conglomerate at the western boundary of the water source, groundwater accumulates in the exploitation area and forms a fault water-conducting and blocking-type fractured karst water storage structure of gray conglomerate; the maximum exploitation drawdown in the exploitation area during the dry season is determined to be 7 m, the leakage recharge quantity of the fault zone at the initial stage of exploitation is 4009.6 m3/d, the leakage recharge quantity of the fault zone at the end stage of exploitation is 6288.46 m3/d, and the allowable exploitation quantity of the exploitation area in the water source is 4304.43 m3/d; in order to optimize the allocation of the exploitable quantity of groundwater resources in each well of the exploitation area and ensure the continuous, efficient and stable development and utilization of the water source, a Dupuit confined steady well flow analytical model was established based on MATLAB software. The optimal exploitation quantities of each well were determined as Q2 = 1100 m3/d, Q5 = 1500 m3/d, Q6 = 1705 m3/d, and the corresponding total drawdowns during the dry season were S2 = 5.69 m, S5 = 7.85 m, S6 = 7.61 m respectively.
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Geochemical characteristics of siliceous rocks in phosphate beds in central Yunnan region and their indications for the genesis of phosphate deposits
Abstract:
The central Yunnan region is an important phosphate rock base on the western margin of the Yangtze continental block. The phosphate rock occurs in the carbonate rock phosphate-bearing rock series of the lower Cambrian Yuhucun Formation. The lithology is phosphate-bearing dolomite, phosphorite, and intercalated with siliceous rock. Siliceous rock occurs in a banded, massive or lenticular shape accompanied by phosphate-bearing dolomite or phosphate rock layer. Siliceous rock is an important research object for paleoenvironmental indication, stratigraphic correlation, and paleontological evolution records. This paper studies the petrological and geochemical characteristics of siliceous rocks associated with phosphorite in Chengjiang, Yiliang and Luliang areas of central Yunnan. The results show that the ratio of Al/(Al+Fe+Mn) in Chengjiang and Yiliang areas is less than 0.4, and that in Luliang area is greater than 0.4. The rare earth distribution curve shows a gentle left-leaning trend. Ce and Ti show negative anomaly characteristics. The total REE is relatively low and relatively enriched in HREE. The U/Th value is distributed between 1.0 and 8.8, all greater than 1. The Co/Ni ratio is between 0.04 and 0.27, showing the characteristics of relatively rich in Ni and poor in Co. Rock geochemistry indicates that the siliceous rocks in Chengjiang and Yiliang areas are mainly of hydrothermal origin, and the siliceous rocks in Luliang area are mainly of biological origin. Siliceous rocks are associated with phosphate rocks. Combined with regional geological data, it is believed that the huge reserves of phosphate rocks distributed along the Xiaojiang fault are derived from submarine exhalative genesis, forming super-large phosphate accumulation bases such as Chengjiang, Kunyang and Zhenxiong. While the Luliang area is far from the hydrothermal center. The formation of siliceous rocks is related to plankton. The genesis of its small-scale phosphate rocks is mainly of biological origin. It is also believed that submarine exhalative hydrothermal fluid provides temperature conditions for the life explosion. A large amount of phosphorus in the hydrothermal fluid provides abundant nutrients for life, laying a good foundation for the formation of phosphate rocks with huge reserves in this area and the life explosion in the Early Cambrian represented by the Chengjiang fauna.
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Verification of the Interactive Evolution of Multisource Sandy Braided Rivers Based on Flume Experiments—A Case Study of the First Member of the Lower Shihezi Formation in the Xinzhao Area, Hangjinqi County, Ordos Basin
HUANG Zhicheng, XU Qinghai, AN Chuan, YANG Zhiyu, YANG Jun, XU Haowei, TAN Wenmei, WANG Changchang, LI Jiayi
Abstract:
SThe formation mechanism of multi-source braided rivers is challenging to quantify due to the frequent, rapid, and continuous migration and interaction of channels, influenced by factors such as paleo-topography, sediment supply, and hydrodynamic conditions. This results in the constant growth and dissection of mid-channel bars. To investigate the interactive evolution process of multiple braided rivers under different paleo-topographic, hydrodynamic, and sediment supply conditions, this study is based on the source-to-sink characteristics of the multi-source braided rivers in the lower Shihezi Formation of the Xinzhao area in the Ordos Basin. A flume experiment was designed with three distinct topographic zones: valley, slope-break, and gentle slope. Additionally, hydrodynamic conditions and sediment supply rates were set as variables. Three sets of experiments were conducted to quantitatively analyze the impact of these variables on the interactive evolution process of multi-source braided rivers. Each set of experiments was designed with 21, 22, and 10 phases of braided channel deposition experiments respectively, lasting a total of 102 hours. A 3D laser scanner was used for precise sedimentary geomorphology monitoring and quantitative sedimentological analysis to study the depositional evolution process of multi-source braided rivers. The results indicate:1)The evolutionary models of channel bars in valley regions can be classified into four end-member types: accretion-erosion-migration bars, accretion-erosion-accretion-erosion bars, stable accretion bars, and stable stagnation bars. 2)Under multi-source conditions, braided river deposits exhibit pronounced differentiation: under uniform sediment supply, sand bodies thin toward the depositional axis; under varying hydrodynamic conditions, slope-break and gentle slope regions form a "left-network, right-bar" configuration (anastomosing channels on the left, isolated bars on the right); with differential sediment supply rates, low-supply braided channels evolve into single-thread, straight channels, leading to laterally homogeneous sandbody distributions.3)Channel bars exhibit length-to-width ratios ranging from 2 to 5, averaging 2.5. In valley regions, steep topographic gradients and strong hydrodynamic forces enhance vertical incision, inhibiting channel bifurcation, while abundant sediment supply promotes the development of longitudinal channel bars aligned parallel to the valley axis. In slope-break zones, reduced basal slopes and weakened hydrodynamics facilitate channel branching, forming composite bars through amalgamation of isolated bars, where two adjacent fluvial systems interact, resulting in widened channel belts. In gentle slope regions, minimal basal slopes and low hydrodynamic energy favor the preservation of isolated bars. 4)Basal slope is the primary control on channel bar density, with lower slopes correlating to higher bar densities. 5)Basal slope, hydrodynamic intensity, and sediment supply rate synergistically govern bar scale and abundance: under reduced hydrodynamic intensity, valley regions exhibit increased bar scale and abundance, slope-break zones show decreased bar scale but increased abundance, and gentle slopes display decreased bar scale and abundance; under reduced sediment supply, valley regions experience decreased bar scale and abundance, slope-break zones exhibit decreased bar scale but increased abundance, while gentle slopes develop increased bar scale but decreased abundance.
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Jurassic Marine Salt and Its Resource in the Shenglihe Depression, Northern Qiangtang Basin
Wu Zhenhan, Chen Yun, Ji Changjun, Liu Zhiwei, Wang Qian, Zhang Lili
Abstract:
Marine evaporite formed in Upper Jurassic Suowa Formation, Middle Jurassic Xiali and Buqu Formations, Lower Jurassic Quemoco Formation and Upper Triassic Bagong Formation, respectively. Thick salt layers are discovered in middle-lower section of the Xiali Formation, Middle Jurassic in the Shenglihe Depression, Northern Qiangtang Basin. Total thickness of the salt is 351m, and amount of salt layers is 32 with thickness of separate layer of salt range from 2m to 50m. Color of the salt changes from violet red, light red and pink to white and grey, and the salt layers are interbedded with gypsum, marl, mudstone and limestone in the Middle Jurassic Xiali Formation. Major component of the salt is sodium chloride (NaCl), containing Na 17-38%, Cl 20-50%, Mg, 1.0-1.9 and Ca 0.4-5.1%; and some salt layers contain potash with K 0.5-1.7%. Salt as thick as 300-350m, 200-300m, 100-200m and 50-100m cover area of 46km2, 55 km2, 117km2 and 218km2, respectively, in the Qingshuihu foreland basin, central Shenglihe Depression. It is revealed that halite resource of 100 billion-tonne exists in the Shenglihe Depression, which indicates potential for exploration of moraine potash in the Qiangtang basin.
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Development Pathways and Practical Explorations of CGS for Geoscience Popularization in the New Era
Abstract:
Scientific innovation and popularization are the two wings driving innovative development. With the comprehensive implementation of China's innovation-driven development strategy and the accelerated advancement of geological work in the new era, geoscience popularization has become a crucial component in supporting geological scientific innovation and enhancing public geoscientific literacy. This paper provides a systematic and objective analysis of the evolving environment for geoscience popularization, highlighting the achievements in science popularization of CGS,arguing that it faces new tasks and challenges in the new era while possessing unique industry strengths. It emphasizes the need to acknowledge both the achievements and shortcomings of past geoscience popularization efforts and to scientifically plan pathways and practical measures for its innovation-driven development. The author recommends that geological industry units collaborate closely, engage in prudent planning and steadfast execution, and coordinate efforts across multiple dimensions to advance geoscience popularization. By synergizing the popularization of geological knowledge with scientific innovation, we can more effectively improve the public service capacity of geological information and contribute to elevating citizens' scientific literacy.
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Mesonorm Calculation Method: A Useful Tool for Petrological Studies
GE Manjun, WANG Yang, XIAO Shuting
Abstract:
Mesonorm is a norm calculation scheme from whole-rock chemical analyses of igneous or high grade metamorphic rocks. Compared with the widely used CIPW norm scheme, a major improvement of the mesonorm scheme is introducing the biotite (Bi) norm in its calculation procedure. Thus, the mesonorm scheme produces less content of K-feldspar (Or) norm and more content of quartz (Q) norm for most igneous and high grade metamorphic rocks. Consequently, the mesonorm provides a more realistic estimation of the K-feldspar content in the rocks. In this paper, the procedure of mesonorm calculation is presented briefly, and several case studies are provided to validate the advantages of the mesonorm as a tool for normative calculations. For the naming and classification of the mica contained plutonic rocks, the norms by mesonorm calculations project into the right places of the QAP and the Q’-ANOR diagrams, while the CIPW norms performs badly in the cases. The mesonorm projections of five categories of granitoids, which are defined by the chemical-mineralogical criteria, illustrates distinguishable patterns in the Q’-ANOR diagram among the five categories. This finding suggests that the mesonorm projected Q’-ANOR plot is a potential scheme to identify the chemical-mineralogical categories of granitoid suites and discriminate their tectonic environment. The bulk rock densities of the intermediate- and high-grade ortho-metamorphic rocks in eastern China, which are derived from the rock-forming mineral portions by mesonorm calculations, demonstrate a good correlation with their bulk SiO2 contents, which is SiO2 (wt%) = -69.069 × ρ + 259.741 (the unit of density ρ is 103kg/m3). Thus the bulk SiO2 content of the lower crust of eastern China is estimated to be less than 53 wt%, and implies a basic composition in chemistry. In summary, we argue that the mesonorm provides more suitable norms than the CIPW norms for common igneous and high-grade metamorphic rocks. However, the public softwares for mesonorm calculation are still lacking, and more programming works are needed.
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New Discovery of Mantle Peridotite in the Zhuyangguan-Xiaguan Fault Zone, North Qinling
ZHAI Wenjian, ZHAO Huan, WANG Kun, ZHAI Wenfang, YAO Shuai
Abstract:
Through 1:50,000 regional geological survey, two mantle peridotite blocks were identified within the Zhuyangguan-Xiaguan Fault Zone. These blocks occur as lensoidal bodies concordant with the tectonic schistosity, hosted within a biotite-quartz schist matrix, and are in fault contact relationships with the surrounding rocks. The core of the blocks is dominated by metamorphic peridotite, with serpentinization alteration intensifying towards the margins, gradationally passing into serpentinite. Geochemically, the rocks are characterized by high MgO, Cr, and Ni contents, relatively low FeOT, TiO?, Yb, and rare earth element (REE) contents, and Mg/Si ratios(1.18 to 1.29). They exhibit an LREE-enriched, flat REE distribution pattern, enrichment in Cs, Th, U, Pb, and Sr, and depletion in Zr, Hf, Ti, and P. These characteristics are diagnostic of mantle peridotites within supra-subduction zone (SSZ) type ophiolites. Integrating previous research findings, the metamorphic peridotite blocks within this fault zone, together with the newly identified metamorphic pyroxenite blocks, metamorphic gabbro blocks, metamorphosed siliceous rock blocks, and the albite-actinolite schist matrix recognized in this survey, collectively potentially constitute an ophiolite sequence. These relationships suggest that the Zhuyangguan-Xiaguan Fault Zone may represent an Early Paleozoic ophiolitic tectonic mélange belt.
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From Discourses on Mineralogy to Ancient Mineral Records: The Archaeological Mineralogy and Petrology Pioneered by Zhang Hongzhao
Abstract:
Faced with a scarcity of qualified personnel and insufficient field survey data during the nascent stage of Chinese geology, Zhang Hongzhao (1887-1951), a founding figure of the discipline, pioneered a novel research paradigm: archaeological minerology and petrology. He achieved this by systematically investigating geological clues within traditional Chinese literature through a Western academic lens and applying rigorous scientific methodologies for collation and analysis. Zhang produced a prolific body of work in this field. His contributions not only established foundational standards and provided direction for Chinese geology, but certain publications, such as?Shi Ya?(《石雅》), also garnered significant public attention, effectively advancing the dissemination of geological knowledge. This article comprehensively examines Zhang Hongzhao""s key works that integrate ancient texts with modern geological methods. It further analyzes the academic foundations, methodological framework, and explores the enduring scholarly value and societal significance of this distinctive research trajectory.
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Geochemical characteristics of stream sediment survey and prospecting prediction of fluorite deposit in Kalaqin banner, Inner Mongolia
Abstract:
Objective：Kalaqin Banner is located in the Au Ag Fe Cu Pb Zn metallogenic belt on the northern edge of the North China Platform, with superior geological conditions for mineralization. It is rich in lead-zinc, gold, and fluorite minerals, among which fluorite is a strategic mineral and its deposits are particularly noteworthy. The purpose of this article is to study the distribution characteristics, correlation, single element anomaly characteristics, and combination characteristics of anomalous elements in the Kalaqin Banner area. Based on this, the prospecting area is delineated and the next direction for prospecting is pointed out. Methods：The main research method used in this article is 1:50000 water sediment measurement, including field sample collection, sample testing (ICP-MS, ICP-AE, ES, XRF, AFS), data processing, and comprehensive analysis. Results：Research has found that fluorite, Pb, Zn, and Ag in the area have good prospecting potential. Four prospective areas with good prospecting potential have been identified, namely: Daxigou fluorite, lead-zinc silver polymetallic prospecting prospective area, Lazigou North fluorite prospecting prospective area, Lazigou South fluorite, lead-zinc silver polymetallic prospecting prospective area, and Qianaobaogou lead-zinc silver polymetallic prospecting prospective area. Analysis and suggestions for future work have been conducted on these areas. Conclusion：The entire region is enriched in elements such as F, Pb, Au, W, Ag, Mo, Zn, while elements such as Cu, Sn, Be, Li, Nb are depleted. F. Au and Bi elements have a high possibility of mineralization; Mo, Pb, and W elements have a high possibility of mineralization. Based on the abnormal characteristics of sediment in the water system and the screening and evaluation results, combined with the geological conditions of mineralization such as strata, structures, and magmatic rocks in the area, four prospecting areas have been delineated, which is of great significance for the future exploration of fluorite deposits in the area. In the semi-arid mid low mountain landscape area, the 1:50000 water system sediment measurement method for mineral exploration can effectively narrow the exploration range, quickly determine the exploration direction, delineate the exploration prospect area, and provide direct and reliable geochemical information for geological exploration.
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Analysis of Differential Characteristics and Differentiation-Evolution Mechanisms of Sags in the Changling Fault Depression?
Cai YuXun, Li Tao, Zhang JiaChang, Miao Meng, Hu Jia, Liu JiaYu, Yue Tong, Binghua Yang
Abstract:
The Changling Fault Depression, one of the largest composite fault-depression structures in the southern Songliao Basin, exerts critical control on hydrocarbon accumulation through its multi-stage tectonic evolution and differential development of secondary sags. This study integrates 3D seismic data and regional geological surveys to identify structural styles of secondary tectonic units and analyze sag differentiation within the depression. By combining balanced cross-section techniques with 3D Move structural restoration, we systematically reconstructed the 3D tectonic framework, deciphered the spatiotemporal evolution of fault systems, and simulated migration patterns of subsidence centers. Key findings include: (1) The conjugate interaction of NNE-trending basement faults and NW-oriented transfer faults governs sag differentiation, forming distinct structural zones—a western double-fault graben, a central composite half-graben, and an eastern volcanic basement-modified sag. (2) The 3D dynamic model reveals a systematic shift of subsidence centers from Shenzijing to Qianbei and then to Chaganhua, driven by coupling mechanisms between differential fault extension and basement responses. (3) Innovative breakthroughs in 3D structural analysis methodology were achieved, establishing for the first time a technical workflow of "3D dynamic modeling-fault system co-evolution-subsidence migration constraints," which overcame the precision challenges in structural restoration of volcanic basement-modified sags. This research provides essential tectonic constraints for optimizing deep hydrocarbon exploration targets in the Changling Fault Depression, while its 3D structural analysis framework offers a methodological paradigm for studying complex fault-depression basins.
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Link between the 8.2 ka cooling event and variations in solar insolation and latitudinal energy gradients
Li Yanyan, Liang Zhong, Wang Jian, Zhou Chenghong, Chen Yumeng, Sun Wei
Abstract:
The 8.2 ka cold event is a globally recognized abrupt climate change event in academia, regarded as the boundary between the early and middle Holocene. Current research has reached a relatively consistent understanding of its spatial distribution and manifestations, onset and duration, and internal structural characteristics, but there remains disagreement regarding its causes. While most studies attribute it to the influx of glacial meltwater into the North Atlantic, which weakened the Atlantic Meridional Overturning Circulation (AMOC), some research suggests a connection to changes in astronomical solar radiation. This study, based on the newly released high-precision DE441 ephemeris data, reconstructs the astronomical solar radiation energy at the equator (0°) and 60°N during the summer and winter half-years from 7.5 to 9 ka BP, and calculates the latitudinal energy gradient between them to explore the temporal correspondence between the 8.2 ka cold event and astronomical solar radiation. The results indicate that, on a centennial scale, both the astronomical solar radiation energy at the equator (0°) and 60°N, as well as the latitudinal energy gradient, exhibited significant low values during the period of 7.9–8.45 ka BP. This aligns closely with the onset and termination of the 8.2 ka cold event as recorded in high-resolution Greenland ice core δ18O, Northern Hemisphere stalagmite δ18O, and pollen data. Thus, it is inferred that the weakening of astronomical solar radiation energy at both high and low latitudes, along with the decline in the latitudinal energy gradient, collectively led to synchronous cooling in the mid-to-high latitudes, serving as a key factor in triggering the 8.2 ka global cold event. This study provides a new perspective for understanding the causal mechanisms of Holocene cold events.
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Discussion on the Formation Mechanism of Aral complex granitic plutons in Koktokay Area, Northern Xinjiang
LIN XinWang, WANG Xing, ZHANG YangFeng, ZHAO Duanchang, ZHAO Jianglin
Abstract:
Alar rock mass exposed in the Koktokay area of northern Xinjiang is composed of different types of intrusive units and has typical characteristics of complex granite basement. This study obtained LA-ICP-MS zircon U-Pb isotope ages of 217.3 ± 3.8 Ma, 218.6 ± 2.4 Ma, and 216.5 ± 6.3 Ma for medium to fine-grained biotite diorite granite, medium grained porphyritic diorite syenite granite, and medium coarse porphyritic diorite syenite granite, respectively, which are products of Late Triassic magmatic activity. The rocks are characterized by high silicon and low titanium, rich in potassium and aluminum, and poor in magnesium. The main body is the peraluminous potassium basalt series, with a differentiation index (DI) of 83.71-92.52 and an average value of 88.63, reflecting a high degree of magma crystallization differentiation; Strong negative europium anomaly (δ Eu=0.30-0.72) may be related to the fractional crystallization of plagioclase; Enriched with large ion lithophile elements Rb, Th, U and rare earth elements La, Ce, Nd, Sm, deficient in Ba, Nb, Sr, P, Ti, it belongs to a typical low Ba, Sr granite, indicating that the rock mass may be a product of low-level partial melting of crustal materials. The 176Hf/177Hf values of medium grained porphyritic biotite syenogranite and medium coarse-grained porphyritic biotite syenogranite are 0.282642-0.282800 and 0.282675-0.282763, respectively. The ε Hf (t) values range from -0.02 to+5.73 and+1.03 to+4.37, and the t DMC model ages are 759-1052 Ma and 827-993 Ma, respectively, indicating that the magma may have originated from partial melting of crustal materials from pre Cambrian microcontinents and the involvement of mantle derived materials. The rock body exhibits strong differentiation characteristics of I-type granite or A-type granite, with some exhibiting characteristics of S-type granite, indicating that the magma origin may not be a single source melting, or there may be a mixture of mantle derived magma and crustal material magma source areas, and magma evolution may involve both crystallization differentiation and assimilation mixing. Based on regional data, it is believed that the Alar complex granite was formed in an intraplate extensional environment, and its magma mainly comes from partial melting of crustal materials, with a small amount of mantle material possibly infiltrating into it. The heat source required for multi-source magma mixing in the lower crust may be related to the remote effects of the Siberian super mantle plume activity.
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Machine learning empowers provenance analysis: A geological lens in the new era.
LIU Fangbing, WANG Zhe, WANG Yanying, ZHENG Jiashu
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Provenance analysis is a pivotal technique in geological studies, which elucidates the origins and transportation pathways of materials by examining the geochemical and mineralogical attributes of sediments, soils, and rocks. This approach holds significant scientific value for deciphering geological history, paleoclimate variations, contemporary surface processes, crustal thickness reconstruction, and environmental evolution. Despite the accomplishments of conventional source analysis methods, such as heavy mineral assemblage analysis, zircon U-Pb dating, and isotope tracing, in delineating paleogeographic configurations and tectonic activities, they often grapple with difficulties like technical intricacy, high costs, lengthy procedures, and the need for sophisticated data analysis skills. In light of the rapid advancement in big data and machine learning technologies, machine learning has emerged as a promising tool in source analysis, offering robust data processing and the ability to unravel complex nonlinear relationships. This study first synthesizes and systematically evaluates recent advancements in machine learning applications for provenance analysis, supported by empirical case studies. Subsequently, we conduct a comparative assessment of ML methodologies against conventional approaches, elucidating their respective strengths and limitations, while outlining future research trajectories for ML-driven provenance investigations. It also assesses the comparative strengths and limitations of machine learning approaches versus traditional methods and offers a perspective on the future role of machine learning in the domain of source analysis. The research demonstrates that machine learning can enhance the precision and efficiency of source analysis, while also providing innovative data-driven strategies for earth science inquiries.
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Glacial geomorphology and Quaternary ice age sequence at Yajiageng, Gongga Mountain, western Sichuan
ZHANG Xinyao, LI Mengzhen, CHEN Qingshuo, LUO Weijia, LIU Gengnian.
Abstract:
Objectives: This study aims to establish a detailed chronology of Quaternary glaciations in the Yajiageng area of Gongga Mountain, eastern Tibetan Plateau. It seeks to clarify the timing and extent of past ice advances. Methods: We applied some methods in this study including field geomorphological survey, cosmogenic nuclide dating, laboratory analysis and ESR for age calculation. Results: In this paper, on the basis of field glacier geomorphological survey and 10Be exposure age analysis of moraine gravel. Five stages of Quaternary glaciation in Yajiazhi area, namely, the Little Ice Age, the New Ice Age, the Last Ice Age, the MIS 5 Ice Advance, and the MIS 6 Ice Advance, are identified. Conclusions: Yajiageng preserves evidence of five Quaternary glaciations, resolving debates on the timing of pre-LGM advances.
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Genesis of the Gaoerqi silver-lead-zinc deposit in the western segment of Great Xing’an Range, NE China: Evidence from fluid inclusions and S-Pb isotopes
CAO Lei, ZHANG Cheng, MA Jiajun, ZHANG Qing, Xu Liquan, LUO Chao, ZHANG Tingting, LIU Yuchao, LI Luyao
Abstract:
The Gaoerqi deposit is a large silver-lead-zinc deposit newly discovered in Abaga Banner, Inner Mongolia, the western segment of Great Xing’an Range, indicating that the area has huge silver polymetallic prospecting potential. However, the genetic mechanism of the silver-lead-zinc deposit in the western section of the Great Xing’an Range is still unclear, and the difference in mineralization characteristics between it and the northern and southern sections is also unclear. This paper selects the Gaoerqi deposit to carry out research on the thermodynamics and isotope geochemistry of ore-forming fluids. The results show that the ore-forming fluids of the Gaoerqi deposit generally belong to the medium-high temperature (199~420℃), medium-low salinity (1.4%~17.9% NaCl.eqv) H2O-NaCl±CO2±CH4 system. The sulfides in-situ S (+6.78‰~+9.27‰) and in-situ Pb (208Pb/204Pb=38.301~38.338, 207Pb/204Pb=15.588~15.598 and 206Pb/204Pb=18.451~18.460) indicate that its ore-forming materials come from magma and surrounding rock strata. Fluid boiling accompanies the entire mineralization process, especially in the quartz-carbonate-coarse-grained arsenopyrite stage (S1); In the early stage of the quartz-polymetallic sulfide stage (S2), pulsed hot fluids are superimposed, and in the late stage, the system cools down and fluid mixing occurs, which leads to the gradual enrichment and precipitation of lead, zinc and silver in the main mineralization stage; The quartz-carbonate stage (S3) belongs to the late mineralization stage, and no sulfides appear. Comprehensive analysis shows that the mineralization characteristics and genetic mechanisms of the silver-lead-zinc deposits in the western section of the Great Xing’an Range, represented by the Gaoerqi deposit, are significantly different from those in other regions. It is proposed that the deposits are the product of magmatic activity under the background of oceanic subduction in the late Paleozoic, and a regional silver-lead-zinc mineralization model is constructed based on this.
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Research on key parameters and error control for converting the grade of titanium-iron sand ore
Abstract:
Aiming at the problem of severe cumulative error in determining the grade of titanium-iron sand ore by chemical analysis, this study takes the Weiliu titanium-iron sand ore in Funing County, Yunnan Province as an example to systematically analyze the error sources and control measures of the key parameters for determining the grade of titanium-iron sand ore by chemical analysis. The research findings are as follows: (1) There is a significant deviation in the TiO? distribution rate of ilmenite obtained by phase analysis: It is difficult to achieve effective phase separation for ilmenite and titanium-iron mixtures and other titanium-containing minerals. TiO? from ilmenite, titanium-iron mixtures and limonite is mistakenly included in the TiO? distribution rate of ilmenite (77.50%), resulting in an overestimation of the grade. Through the micro-area analysis of scanning electron microscopy energy dispersive spectroscopy (EDS) and the calculation of titanium element distribution equilibrium, the true distribution rate of TiO? in ilmenite was determined to be 57.24%. Using this value can reduce the error by 35.39%. (2) The direct application of wet weight in grade calculation will result in an error of 28.57%. (3) The results of the micro-area composition analysis by scanning electron microscopy energy dispersive spectroscopy (EDS) showed that the measured content of TiO? in ilmenite (51.72%) was 0.94% lower than the theoretical content. The theoretical content was adopted in the general survey stage, while the measured values should be used in the detailed survey and exploration stages.Based on the above findings, three error control measures are proposed:①Chemical phase analysis combined with process mineralogical research methods such as scanning electron microscopy energy dispersive spectroscopy (EDS) to comprehensively determine the distribution rate of TiO? in ilmenite; ②The dry weight was measured by the water injection method and the large gravel was removed.③The content of TiO? in ilmenite was measured in the micro-area by scanning electron microscopy energy dispersive spectroscopy (EDS).
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A short introduction to the life and achievements of the geologist Friedrich Solger
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The German geologist Friedrich Solger was born in Berlin in Germany in 1877 and obtained his doctoral degree at the University of Berlin in 1902. He was professor at the University of Beijing from 1910 to 1913, and carried out geological exploration in China. In 1914, he went to Qingdao to attend the war between Germany and Japan. After being captured, he became a prisoner in Matsuyama and Bandō in Japan and went back to Germany in 1920. From 1921 on, he was appointed as professor at the University of Berlin. He died in East Berlin in 1965. Solger did important contributions to the geology of Germany and China.
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The siliceous genesis of Upper Permian Dalong shale in eastern Sichuan and its coupling relationship with organic matter enrichment
DU Anye, Ye Yuehao, Liu Shugen, Wang Hua, Song Jinmin, Li Zhiwu, Jin Xin, Liao Zhifang, Zhang Zhaoyi, Zhang Zhaoyi, Ma Xiaogang
Abstract:
Objectives: In the late Permian period, influenced by the mantle plume event of Mount Emei, a set of organic-rich siliceous shale was deposited in the Kaijiang-Liangping trough on the northern margin of the Sichuan Basin. This set of siliceous shale lacked the input of continental materials and was formed in a typical clear water sedimentary environment. The siliceous genesis of this set and its coupling relationship with organic matter enrichment were studied, and on this basis, the development model of siliceous shale was established. In order to provide a reference for the exploration and development of Permian shale gas. This paper takes the Marine shale of the Dalong Formation of the Upper Permian in the eastern Sichuan region as the research object and conducts detailed core observation, micro-petrological analysis and whole-rock geochemical analysis. Results: (1) The lithology of the organic-rich mud shale section of the Dalong Formation is mainly siliceous shale, with a relatively high organic matter abundance, an average TOC of 7.26%. The mineral types are mainly quartz minerals, followed by carbonate minerals, and the content of clay minerals is relatively low. (2) Siliceous organisms mainly come from biological sources. The deep silicon-rich water bodies brought about by upwelling and the overall silicon-rich seawater caused by regional tectonic events provide conditions for the prosperity of siliceous organisms. (3) The enrichment of organic matter is closely related to the enrichment of siliceous matter. The enrichment of both organic matter and siliceous matter in siliceous shale is simultaneously controlled by high primary productivity and the preservation conditions of anoxic-sulfidation reduction environment Conclusions: It reveals that there is a coevolutionary mechanism between the siliceous genesis of shale and the enrichment of organic matter.
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Research Hotspots and Development Trends of Cave Tourism from 2007 to 2024: A Visualization Analysis Based on CiteSpace
WANG Yilin, WEN Yanfang, YANG Xiaoxia, WANG Nan
Abstract:
Objectives: Since 2007, research achievements in cave tourism have been continuously enriched. A systematic review of the literature on cave tourism can provide a comprehensive understanding of the research trends and offer new ideas and important guidance for future research on cave tourism in China. Methods: This paper uses the visualization software CiteSpace to systematically analyze and compare the publication trends, research institutions and authors, journals, and research hotspots of cave tourism in both domestic and international contexts from 2007 to 2024. Results: The results show that: ① The number of domestic research publications showed a fluctuating and decreasing trend, while international research shows a trend of fluctuating growth, and the difference in the number of domestic and foreign cave tourism literature has increased year by year since 2016; ② Research on cave tourism is highly interdisciplinary, involving multiple fields such as geomorphology, hydrogeology, biodiversity, ecological environment, and tourism; ③ Research institutions focused on cave tourism are mainly universities and research institutes in countries or regions with cave and karst landscape resources; ④ Research hotspots in cave tourism include the ecological environment of show caves, evaluation of cave tourism resources, tourism development, cave tourism management, and tourist behavior in caves.
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Spatial Distribution Characteristics and Influencing Factors of Important Geological Heritage Resources in Henan Province
yangyuanyuan, zhangzhonghui, wangtongwen, zhangzibo
Abstract:
Abstract: Located on the southern margin of the North China Plate, Henan Province has experienced complex tectonic movements, resulting in abundant geological heritage resources characterized by a wide distribution and comprehensive variety. These resources form a significant component of China's geological diversity and provide crucial evidence for the evolution of the East Asian continent. Decoding the spatial patterns of these geological heritages can offer an ecological security barrier, a foundation for resource assurance, and a cultural empowerment engine for the rise of the Central Plains.Given this context, this study takes 335 important geological heritage resources in Henan Province as its research subjects. Utilizing analytical tools such as the Nearest Neighbor Index, Imbalance Index, Kernel Density Analysis, and Spatial Autocorrelation, it delves into the types and distribution characteristics of these resources across the province. The results indicate that:(1) The types of important geological heritage resources in Henan Province are relatively comprehensive, dominated by stratigraphic sections, significant mineral and rock production sites, and rock-soil mass landforms.(2) Spatially, these resources exhibit a distribution pattern of "more in the west and less in the east".(3) The Nearest Neighbor Index (R) for these resources is 0.474 < 1, indicating significant clustering characteristics.(4) Natural factors—including geological conditions, topography, rivers, and vegetation—are the primary influences shaping the spatial distribution pattern of important geological heritage resources, with each factor exerting varying degrees of impact.Finally, based on the spatial distribution status of these resources in Henan Province, the study discusses and analyzes their development and utilization. It proposes targeted recommendations aimed at providing theoretical support for the protection and sustainable development of geological heritages in Henan, and supporting their global recognition within China’s geological heritage resources.
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The Reception and Transformation of Geological Institutions in Taiwan by the Chinese Government after Recovery（1945-1949）
Abstract:
After the victory of the Anti-Japanese War, the geological community in Taiwan underwent a transformative period of returning from a colonial academic system and integrating into the Chinese geological scientific community. This paper focuses on the National Government"s reception and reorganization of Taiwan"s geological institutions from 1945 to 1949, exploring the process of their integration with the geological community on the Chinese mainland and promotion of China"s geological discipline against the backdrop of political and social restructuring. The study examines the legacy issues of geological work during the Japanese occupation, analyzes the reception and expansion processes through restructuring the former "Taiwan Geological Survey" into the "Taiwan Provincial Geological Survey" and establishing the new "Taiwan Provincial Marine Research Institute," and presents the collaborative achievements between mainland and Taiwanese geologists in fields such as mineral resource exploration, stratigraphic paleontology, and marine geological surveys. The research shows that this process not only critically inherited the geological legacy of the Japanese occupation but also filled gaps in China"s geological science in areas such as Tertiary marine strata and island tectonics through institutional coordination, talent integration, and academic community building. It strengthened the national identity of Taiwan"s geological community, provided an important case for regional integration in modern China"s scientific development, and highlighted the interactive mechanism between political changes and geological discipline development, as well as their roles and contributions to the national geological cause.
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Hydrochemical characteristics and formation mechanisms of groundwater in the Longgang area，Southeastern Zhejiang Coastal City
ZENG Li, YE Wenrong, HUANG Ji, YUAN Jing, XU Pengfei, ZHANG Yuzhi, LI Mengbi
Abstract:
Objectives: The Longgang area, located in the coastal plain of southeastern Zhejiang, has a complex groundwater seepage field evolution due to historical seawater intrusion and anthropogenic impacts. This study examines its groundwater hydrochemical characteristics and evolution trends. Methods: The study collected a total of 43 water samples (surface water, phreatic water, confined aquifers Ⅰ and Ⅱ) in the study area. Combined with the data from four monitoring wells and historical water samples for comprehensive analysis. Multiple analytical methods were employed—including multivariate statistical analysis, hydrochemical diagrams, ionic ratios, saturation indices, and inverse hydrogeochemical modeling to investigate the spatiotemporal evolution characteristics of hydrochemistry in the region and elucidate the formation mechanisms of water quality. Results: ① Hydrochemical types of the study area: Phreatic water are dominated by Cl·HCO3—Na and HCO3·Cl—Ca·Na types; Confined groundwater(I) are Cl—Na type; Confined groundwater(II) are mainly HCO3·Cl—Na type. ② The aquatic environment of the study area is generally weakly to moderately alkaline, Cation abundance (avg.): Na+>Ca2+>Mg2+>K+, Anion abundance (avg.): Cl->HCO-3>SO2-4. ③ Surface water and phreatic water(domestic well) Primarily controlled by rock weathering and dissolution; Confined groundwater(II) and some phreatic water influenced by combined evaporative concentration and rock weathering; Confined groundwater(I) and most phreatic water significantly affected by evaporation. ④ Major groundwater components result from: dissolution of silicates and halite (rock salt), dissolution/precipitation of calcite and dolomite, formation via cation exchange adsorption. Conclusions: The findings provide significant guidance for the sustainable development and utilization of groundwater resources in the Longgang coastal area of southeastern Zhejiang.
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Ediacaran tectonic transition of West Congo: Chronological and geochemical evidence from two periods of magmatic rocks in northwestern Angola
Abstract:
Ara?uaí-West Congo orogenic belt is the product of the Neoproterozoic Brasilia-Pan African movement. It belongs to the northern branch of the Adamastor Ocean and has developed a complete Wilson cycle. The Aracuai Belt has been studied to a relatively high degree, with the development of granitic mantle related to Neoproterozoic-Cambrian subduction and collision. However, magmatic rocks of this period in West Congo Belt have rarely been reported, and even their existence has been questioned. Whether there are granites related to Neoproterozoic -Cambrian subduction and collision in the West Congo Belt is worth further study. In order to reveal the Ediacaran tectonic transition process of West Congo orogenic Belt, this paper studies the petrology, zircon U-Pb chronology and geochemistry of the newly discovered quartz diorite and quartz diorite in the northwest of Angola, analyzes the genesis of the rocks and the tectonic environment in which they formed. The zircon U-Pb ages of quartz diorite and quartz diorite were 578.0±2.3Ma and 543.9±2.6 Ma respectively, belonging to the middle and late intrusions of the Ediacaran period of the Neoproterozoic. Quartz diorite is rich in hornblende, biotite and plagioclase, belonging to the quasi-aluminous potassium-calc-alkaline series. It has the characteristics of island arc magmatic rocks, enriched with large ion lithophile elements such as Ba and K, deficient in Th, U, Ta, Nb, P, Ti and other high field strength elements, and the rare earth partition curve is right-leaning type of LREE enrichment. It is the product of crust-mantle mixing under subduction mechanism, which can be compared with the G1 suite in Ara?uaí belt. Quartz monzodiorite is rich in biotite and plagioclase and belongs to high potassium calc alkaline peraluminous rock. Compared with quartz diorite, it is rich in K2O, Na2O, Al2O3, P2O5 and poor in CaO, MgO, Fe2O3T. Quartz monzoniorite is the product of partial melting of the mafic lower crust under the post-collision background, which can be likened to the G3 suite in Ara?uaí belt. Studies show that there exists a Neoproterozoic calcium-alkaline magmatic arc related to orogeny in West Congo Belt. The two periods of magmatic rock ages (578 Ma vs. 544 Ma), geochemical characteristics and tectonic backgrounds are significantly different, indicating that the West Congo orogenic belt underwent a tectonic background transformation from subduction to post-collision from the middle to the end of the Ediacaran period.
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Chronology of sandstone type uranium deposits in the Southwest of Songliao Basin and its geological significance
LIN Xiaobin, QIN Mingkuan, JIA Licheng, NING Jun, HE Feng, TIAN Mingming, XING Zuochang, ZHANG Yunlong
Abstract:
Objectives: Chronological study of sandstone type uranium deposits is an important part of uranium mineralization mechanism research and a key to revealing the evolution laws of uranium mineralization. Currently, there is a large amount of data on uranium mineralization chronology in the Songliao Basin, but some of the data have poor reliability or even errors, leading to some erroneous understandings and conclusions. Methods: By integrating previous and self measured uranium lead isotope data from three uranium deposits in the southwestern Tongliao area of the Songliao Basin, namely Qianjiadian, Dalin, and Hailijin, and using an improved whole rock isochronous age fitting method, the uranium mineralization age was re fitted and calculated. Results: The results indicate that the three deposits have consistent uranium mineralization periods, which can be divided into 10 periods: Yaojia Formation sedimentation period, Nenjiang period, Sifangtai period, Mingshui period, Middle Paleocene, Late Paleocene, Middle Eocene, Late Eocene, and Middle Oligocene. Conclusions: The uranium mineralization mainly occurs within several million years after strong compressional tectonic activity, and the ages of uranium mineralization in each stage are consistent with the ages of apatite fission track and magmatic rock, showing the characteristics of "episodic" stage mineralization. The uranium mineralization of the Upper Cretaceous began at the beginning of the structural inversion in the Songliao Basin (88.5 Ma), and each mineralization is related to the strong tectonic dynamics of the region. It is believed that the genesis of gray mudstone and sandstone in the red variegated rock layers is closely related to the overflow of deep-seated reducing fluids. The favorable prospecting locations are the fluid trap systems formed by faults, folds, and sand bodies on the upper or upper edges of the source rock layers. Red variegated layers such as the Nenwu Member, Sifangtai Formation, Mingshui Formation, and Paleogene have prospecting potential.
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Discussion on Several Issues Concerning the Ancient Chenchuan Lake in the Mu Us Desert
WEN YAN SHENG, LI BAO SHENG, NIU DONG FENG, BAI QING YUAN, WANG FENG NIAN, SI YUE JUN, CHEN MING
Abstract:
Based on field investigations, combined with remote sensing images, relevant lacustrine strata and their chronologies, as well as historical literature, a comprehensive analysis was conducted on the scope, extinction time, and causes of the ancient Chenchuan Lake on the southeastern margin of the Mu Us Desert. The research shows that: (1) The actual area of the ancient lake was wider than the previously thought 100 km2, reaching 130 km2. (2) The extinction of the ancient lake occurred around 300 AD, and the waxing and waning of the ancient lake corresponded to the rising and falling trends of temperatures in China and the Northern Hemisphere. (3) Although the temperatures in China and the Northern Hemisphere have increased several times since 300 AD, the ancient lake has never been restored. The reason is related to the transformation of the neotectonic movement from subsidence to uplift in the Salawusu River Valley since then. Moreover, against the backdrop of neotectonic uplift since 300 AD, the "artificial drainage system" caused by human activities" transformation and destruction of the Holocene lacustrine deposits has also accelerated the loss of surface water within the original ancient lake area, preventing the ancient lake from being restored.
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A review of C-O isotopic characterisitics of pedogenic carbonate and their applications in paleoenvironment reconstruction
Chen Yanbin, Guan Houchun, Xu Jinlong
Abstract:
As an important terrestrial environmental proxy index, the formation and evolution of pedogenic carbonate is controlled by multiple environmental factors, including climate, topography, parent material, biology and time. This paper first introduces the composition, classification, formation mechanism and environmental factors of pedogenic carbonate. Subsequently, it focuses on their C-O isotopic composition, applications in paleoenvironmental reconstruction, and advances in chronology. Studies have shown that the C-O isotopic signatures of pedogenic carbonate are primarily controlled by key parameters such as soil-respired CO? concentration, soil water and soil temperature, providing reliable foundation for the quantitative reconstruction of paleoatmospheric CO? levels, paleo-C3/C4 biomass and paleoprecipitation, paleotemperature, paleoelevation. Geochronological methods such as uranium-series dating further furnish precise temporal framework for the paleoenvironmental reconstruction. However, challenges persist due to the complexity of pedogenic processes, including pedogenic carbonate spatiotemporal heterogeneity, diagenetic overprinting and selective preservation of environmental signals. Finally, this review outlines future research directions and development trends for pedogenic carbonate in the paleoenvironmental reconstruction field.
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Geochronology and geochemical characteristics of volcanic rocks of Biyingaolao Formation in Xinchengzi Basin, Inner Mongolia and their geological significance
Zhou Jian, Hao Xiaofei, Wang Changdong, Yang Zhiliang, Dong Xiaoyu, Wang Jiali, Wu Yanqing, Lin Tianfa, Yubing, Wang Tianqi, Wang Yiming, Zhang Qiang
Abstract:
Abstract:In order to determine the formation age, petrogenesis, and formation environment of the volcanic rocks of the Biyingaolao Group in Xinchengzi Basin, southern part of Greater Xin'an Range, Inner Mongolia, this study conducted zircon U-Pb dating, elemental geochemistry, and Sr-Nd isotope studies on the rhyolitic volcanic rocks within the basin. The LA-ICP-MS zircon U-Pb ages of the rhyolitic volcanic rocks are 132.8±0.79 Ma and 133.1±1.8Ma respectively, indicating that the rocks were formed in the Early Cretaceous. The rocks are rich in Si and alkali, rich in potassium, depleted in Mg, Ca and P, and belong to the peralkali and high potassium calc-alkaline series rocks. The LREE and HREE were obviously fractionated, and the LREE were enriched (LREE/HREE=8.24~11.35), with significant Eu anomaly (δEu = 0.49~0.85). The trace elements are rich in Rb, Ba, K and deficient in Sr, rich in HFSE Th, U, Zr, Hf and deficient in Nb, Ta and Ti. The rocks have high Yb content and Ga/Al ratio, showing similar characteristics to A-type granites. The (87Sr/86Sr) i values of the volcanic rocks range from 0.70243 to 0.70634, εNd(t) ranges from -3.6 to -4.2, and the corresponding two-stage Nd model ages range from 1221 to 1265Ma. Based on the regional geological data and the results of this paper, it is concluded that the volcanic magma of the Baiyingaolao Formation in Xinchengzi Basin originates may originate from anatexis of Paleoproterozoic plagioclase-amphibole rocks in the lower crust, facilitated by mantle-derived magma underplating and associated metasomatism, which is formed in the extensional tectonic setting, and may be related to the subduction of the paleo-Pacific plate to the East Asian continent. The rhyolite volcanic rocks of Baiyingaolao Formation in the basin have high U content, and the U released by the hydrothermal alteration provides uranium source for uranium mineralization in the area.
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Advances in experimental methods for physical simulation of tectonic-geomorphic processes
Yang Bo, Wu Lei, Guan Tao, Yan Bing, Su Nan, Yang Shufeng, Chen Hanlin
Abstract:
This paper systematically reviews the research progress of tectonic-geomorphic physical simulation experiment methods and their applications in Earth system science. The tectonic-geomorphic physical simulation method couples tectonic deformation with surface erosion and sedimentation processes, providing an intuitive and effective experimental approach to study the dynamic evolution of interactions between tectonic activities and surface processes. The article reviews the development history of tectonic-geomorphic physical simulation, introduces in detail the experimental materials, apparatus design, key experimental steps, and scaling issues of this method, and summarizes its research achievements under different tectonic settings, such as compression, extension, and strike-slip. Specifically, it highlights applications in the formation and evolution of fold-thrust belts, the co-control of shortening rates and precipitation rates, the influence of sedimentation processes, and the evolution of drainage systems. Although this method has demonstrated significant potential in theoretical model research, certain technical and fundamental issues remain to be addressed. Future research should focus on further optimizing experimental techniques, expanding the scope of applications, and integrating actual geological contexts to address more complex geological problems. This will provide deeper experimental evidence and theoretical support for understanding the interaction mechanisms between tectonic deformation and surface processes.
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Petrographic and Chronological Characteristics and Geological Significance of Inkisi Formation Sandstones in the Eastern Margin of the Western Congo Orogenic Belt
ZHANG JinLong, ZHANG Hongrui, PAN Zhilong, LUO Dike, XING Weiwei, LIU Silin, YU Long, JIA Pengfei, YANG Ning, LI Qiang
Abstract:
The West Congo orogenic belt is the African part where the S ? o Francisco and Congo cratons converged and collided during the Pan Africa period, and its tectonic evolution has attracted much attention from scholars both domestically and internationally. Conducting research on the stratigraphy of this period is of great significance for exploring the tectonic evolution of the orogenic belt. This study selected the Inkisi Formation sandstone in the foreland basin of the eastern margin of the orogenic belt in northwestern Angola as the research object, and conducted research on chronology and petrology. The results indicate that the minimum detrital zircon age in the Inkisi Formation sandstone is 588 ± 3.0 Ma, and the discrimination diagram indicates that the sandstone was formed in a sedimentary basin under a collision background. The chemical alteration indices (CIA, CIW, PIA) of Inkisi sandstone are 63.34~73.17, 70.82~92.29, and 65.19~89.56, respectively, indicating that the source area was under warm and humid paleoclimatic conditions, and the source rocks underwent low to moderate weathering. A large number of flowing sedimentary structures are developed in the sandstone, with Sr/Ba values ranging from 0.07 to 0.24<0.5. The grain size analysis results show the characteristics of river sedimentation, which collectively indicate that the sandstone was formed in a river sedimentary environment. Based on the results of rock geochemistry, geochronology, and detrital component analysis, this article believes that the Inkisi Formation sandstone in the study area was formed in a basin related to collision environments under the background of active continental margins, which is a response to the West Congo orogeny during the Pan Africa period. It also suggests that the West Congo collisional orogeny continued during the Ediacaran Early Cambrian period.
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Response Characteristics and Structural Analysis of Hydrogen Gas from Faults in the Wuhai Basin to the Yinchuan M4.2 Earthquake
Wang Youpeng, Li Dewen, ZhengNa, Li Xin, ZhaoXiaolong, SuShibing
Abstract:
During the migration and enrichment of fault hydrogen toward the surface, it is jointly influenced by tectonic and non-tectonic factors. Based on the study of the temporal-spatial variations in trace hydrogen concentration in the Wuhai Basin before and after the Yinchuan Ms4.2 earthquake on February 20, 2025, and its relationship with regional tectonic characteristics, this paper obtains the following understandings: (1) Through the analysis of long-term observation records, data characteristics and abnormal factors from multiple stations, it is confirmed that before the Yinchuan Ms4.2 earthquake, the abnormal hydrogen concentration at the Moergou trace hydrogen observation site in the Wuhai Basin is a short-term pre-seismic anomaly. The trend of the abnormal change is that the hydrogen concentration value rises rapidly 4 hours before the earthquake - the earthquake occurs - it turns to decline 1 hour after the earthquake - and it recovers to the background value 37 hours after the earthquake. Compared with the existing research cases, the trend of the abnormal change in hydrogen concentration is basically the same. The differences lie in the shorter imminent earthquake time and a much larger multiple of the abnormal value compared to During the migration and enrichment of fault hydrogen toward the surface, it is jointly influenced by tectonic and non-tectonic factors. Based on the study of the temporal-spatial variations in trace hydrogen concentration in the Wuhai Basin before and after the Yinchuan Ms4.2 earthquake on February 20, 2025, and its relationship with regional tectonic characteristics, this paper obtains the following understandings: (1) Through the analysis of long-term observation records, data characteristics and abnormal factors from multiple stations, it is confirmed that before the Yinchuan Ms4.2 earthquake, the abnormal hydrogen concentration at the Moergou trace hydrogen observation site in the Wuhai Basin is a short-term pre-seismic anomaly. The trend of the abnormal change is that the hydrogen concentration value rises rapidly 4 hours before the earthquake - the earthquake occurs - it turns to decline 1 hour after the earthquake - and it recovers to the background value 37 hours after the earthquake. Compared with the existing research cases, the trend of the abnormal change in hydrogen concentration is basically the same. The differences lie in the shorter imminent earthquake time and a much larger multiple of the abnormal value compared to the background value. (2) Through the relationship between the regional tectonic pattern and short-term anomalies, it is believed that the abnormal increase in hydrogen concentration at the Moore Trench trace hydrogen observation point is related to specific tectonic positions. The Moore Trench trace hydrogen observation point is located on the hanging wall steep slope of a normal fault at the mountain-basin transition position in the northern segment of the west margin fault zone of Zhuozi Mountain. In the regional tectonic pattern, the area where the observation point is located has a certain tensile component, which is conducive to the rapid migration of a large amount of hydrogen enriched underground to the surface. (3) Geological structures and their activities (such as stress changes and ruptures), as well as the environment, can affect the migration and diffusion of fault hydrogen. Even within the same fault zone, the changes in fault hydrogen concentration will vary due to factors such as the tectonic state, stress changes and groundwater at different locations. Studying the coupling between geological structures and their activities and the physical and chemical properties of fault hydrogen is of great significance in the field of earthquake preparation and other aspects. These understandings provide a basis for the response of the abnormal fault hydrogen concentration in the Wuhai Basin to earthquakes and the relationship with tectonics. At the same time, they also have certain guiding significance for the layout of underground fluid observation stations.
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Short wave infrared ( SWIR) spectral characteristics of alteration minerals and applications for ore exploration in Huangjindong orogenic gold deposit,northeastern Hunan
ZHANG Chuangye, ZHOU Yueqiang, ZHANG Yunfei, WU Jun, ZHANG Shengwei, MEI Xiao, SUN Jiandong, WEN Zhilin, LIU Lei
Abstract:
Objectives: The northeastern Hunan region within the Jiangnan Orogen hosts multiple large gold deposits, constituting a significant gold metallogenic belt in China with abundant gold resources. The Huangjindong Gold Deposit, a representative deposit in this area, features substantial reserves and high-grade mineralization. Gold mineralization in this district is closely associated with hydrothermal alteration, with common alteration minerals including sericite, siderite, and montmorillonite.As an efficient exploration technique, Short-Wavelength Infrared (SWIR) spectroscopy enables rapid identification of alteration mineral assemblages and their relative abundances, providing critical data support for alteration mineral mapping. Methods: Based on short-wave infrared spectroscopy (SWIR), this study conducted hyperspectral scanning analyses on core samples from five drill holes in the ore vein of the Huangjindong Gold Mine. By identifying the spectral characteristics of alteration minerals and analyzing the absorption peak position (POS2200) and crystallinity (IC value) of sericite, the spatial patterns of alteration minerals in the mining area were revealed. Results: More than 10 main alteration minerals were identified, with sericite being the dominant one. The POS2200 values of sericite mainly range from 2196 to 2210 nm, and the IC values range from 0.05 to 1.96. The mean POS2200 and IC values of sericite in alteration zones from different drill holes show a gradually increasing trend from west to east. Conclusions: Research reveals significant spatial distribution patterns of alteration minerals across drill holes from west to east: The POS2200 value of sericite progressively increases, indicating enhanced acidity of vein-forming hydrothermal fluids; concurrently, sericite illite crystallinity (SWIR-IC) gradually decreases, demonstrating declining fluid temperatures and confirming west-to-east migration of ore-forming fluids along the vein. A temperature attenuation model based on SWIR-IC was established, pinpointing the hydrothermal center at coordinates (x? = -238.1, y? = -859, z? = -2150). This validates the model's efficacy in tracing hydrothermal pathways and locating mineralization centers, providing critical guidance for mineral exploration. The study offers novel insights for interpreting alteration signatures at the Huangjindong Gold Deposit and delivers a scientific foundation for regional prospecting strategies.
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Estimation of granite erosion rate with cosmogenic nuclide Be-10 exposure dating technique
LIANG Xingjiang, CHEN Luming, ZHANG Zhigang, ZHENG Chaogang, ZHAO Dan, LI Yiman, LU Nanxi, ZHANG Hongmei
Abstract:
Terrestrial in situ cosmogenic nuclide(TCN)10Be exposure dating method is currently one of the most successful dating methods for glacier geomorphology, and this technology has made significant contributions to global glacier geomorphological dating. During the dating process, granite samples are usually selected for dating. However, granite exposed over millennia is subject to weathering, which reduces the concentration of cosmogenic nuclide Be-10 on the surface, leading to an underestimation of the exposure age of the landform. Thus, we aim to quantify the erosion rate of granite over millennial timescales to improve the accuracy of cosmogenic nuclide exposure dating. This application is crucial for understanding evolution of glacial landforms. This study focuses on the Paleo-Daocheng ice cap, where the Be-10 exposure dating technique was applied to determine the surface exposure ages of granites with varying degrees of weathering. Six granite samples sites and twelve Be-10 age samples were processed. By combining the weathering thickness difference, the erosion rates of granite samples were estimated. The results from six granite sample sites and twelve Be-10 age samples indicate that the erosion rate of granite in the Daocheng Ancient Ice Cap area ranges from 1.2 mm/ka to 3.5 mm/ka. This study provides a reliable reference for estimating sample erosion rates in cosmogenic nuclide exposure dating.
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U-Pb Zircon Ages, Geochemical Characteristics, and Geological Significance of Granodiorites from the Shartolgai Copper Deposit in Darhan Mumingan Banner, Inner Mongolia
Li Jianwei, Mi Kuifeng, Wei Zhengyu, Zhang Baotao, Hu Zhaoguo, Mei Zhenhua, Sun Feng
Abstract:
Numerous copper-polymetallic deposits are distributed in the border region between China and Mongolia. The Shartolgai Cu-Mo deposit, located in Darhan Mumingan United Banner, Inner Mongolia, has undergone multiple exploration campaigns since its discovery, providing preliminary insights into the geological characteristics of the deposit. This study reveals the U-Pb concordant zircon age of malachite-altered granodiorite is 293.0 ± 0.96 Ma, while the unaltered granodiorite is 294.1 ± 0.79 Ma, indicating that the magmatic and metallogenic events occurred during the Early Permian. The granodiorites are characterized by high Al?O? (13.05–15.01 wt%) and Sr (161–582 ppm) contents, and low Y (6.67–18.39 ppm) and Yb (0.78–2.33 ppm) contents, suggesting they are adakitic rocks with arc magmatic characteristics. Furthermore, their εHf(t) values range from +4.5 to +11.3 and +7.5 to +10.6, with TDM2 values of 1028–589 Ma and 831–631 Ma, respectively, indicating that the parent magma originated from partial melting of subducted oceanic crust. Based on regional tectonic studies, the authors propose that the Early Permian granites in the Mandula region were formed in a southward subduction setting of the Paleo-Asian Ocean.
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Geological Characteristics, Chronology, and Geochemistry of the Early Devonian Tousuquan Formation Volcanic Rocks in Yaleman Area of the Eastern Tianshan Constraints on the Tectonic Environment
zhang ya guang, XING Weiwei, MA Mengling, LI Qiang, YA Yu, LI Zeyang, GUO Shien
Abstract:
A set of intermediate and acid volcanic lava, volcanic tuff and volcanic breccia are developed in Yaleman Tousuquan formation in the eastern Tianshan. The magma evolved from neutral to acidic from early to late, and developed explosive facies, effusive facies and subvolcanic facies, with seven eruption rhythmic cycles. According to LA-ICP-MS zircon U-Pb isotopic dating, the rhyolite age of Tousuquan Formation is 406±3.0Ma (MSWD=0.35), and the age is early Devonian. Rock geochemistry shows that the volcanic rocks of Tousuquan formation have the characteristics of medium aluminum (13.20%~18.10%), rich in sodium and poor in potassium (K2O/Na2O=0.10~0.67), and belong to the high differentiation low medium potassium calc alkaline rock series; The total amount of rare earth elements is relatively high (∑ REE=98.7×10-6~214×10-6), LREE is enriched, while hree is depleted (LREE/HREE=3.75~4.58), Eu has no obvious negative anomaly (δEu=0.62～0.92), large ion lithophile elements Rb, K, Ba are significantly enriched, and high field strength elements Nb, Ta and Ti are depleted. The geochemical characteristics show that the volcanic rocks of Tousuquan formation have the characteristics of mantle remelting volcanic rocks, and the crustal materials were assimilated in the process of magma upwelling, and the tectonic environment is the continental margin arc environment under the subduction background.
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Mining to save the country: The first national mining and metallurgy geology joint exhibition in 1934
Abstract:
In 1934, the Ministry of Industry of the National Government and the Ministry of Education jointly with the national geological survey and research institution successfully held the first large-scale modern China national mining and metallurgy geology joint exhibition in Tianjin National Beiyang Institute of Technology, for the purpose of observing and discussing, spreading new knowledge and revitalizing industry. Under the cooperation of the political and business circles, the activity space of mining and metallurgy exhibition, exchange and cooperation at home and abroad has been built, which is of great benefit to the promotion of intellectual knowledge, academic contention, scientific and technological progress and industrial revitalization of the Chinese people. The first mining and metallurgy exhibition with plenty of treasures and celebrities and powerful effect, has attracted wide attention from all walks of life, promoted the historical process of recovering rights and developing wealth in modern China, and highlighted the important position of mining and metallurgy exhibition in modern China"s social publicity and mobilization, ideological enlightenment and patriotic education, mining to save the country and the long-cherished desire of the nation and the people.
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Rutile and Apatite U-Pb dating for the Anglonggangri amphibolite and granodiorite, Xizang, and the geological significance
WANG Huan, wangchunlian, wangqingfei, wangliqiang
Abstract:
The rutile and apatite U-Pb dating is one of the important methods in the study of diagenetic geochronology. However, there is often a phenomenon of inconsistency or decoupling between the U-Pb timing of rutile and apatite and zircon in the same rocks. It has caused the problems to effectively constraint the formation timing of rocks, especially in the region with multi-stage magmatism. In this study, the rutile and apatite U-Pb ages for the Anglonggangri amphibolite and granodiorite were dated. These ages also have large derivations from the corresponding zircon U-Pb ages. Based on previous studies on the granites developed in the Anglonggangri area, as well as the timing of magmatism in the neighboring areas of Zuozuo-Xiongba, this study analyzes the reasons for the inconsistent U-Pb ages between rutile and apatite and zircon. It is believed that the regionally widespread multi-stage magmatic activities have led to the reset of the U-Pb closed system of rutile and apatite in the Anglonggangri amphibolite and granodiorite. The U-Pb ages recorded by rutile and apatite reflect magmatism of the Late Cretaceous-Early Paleocene, Eocene, and Oligocene-Miocene, respectively. When using the rutile and apatite U-Pb ages to determine the timing of their hosted rocks in the areas with multi-stage magmatism, someone should be cautious and should carefully evaluate the real geological significances on the rutile and apatite U-Pb isotopic systems.
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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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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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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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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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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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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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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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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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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:
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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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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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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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DENG Jinfu, LIU Cui, FENG Yanfang, XIAO Qinghui, DI Yongjun, SU Shangguo, ZHAO Guochun, DUAN Peixin, DAI Meng
2015,61(4):717-734, DOI:
Abstract:
In this paper, we discuss and review the common igneous petrological diagrams, including classification, chemical parameters, and discrimination of tectonic settings. We have reviewed the original petrological meaning of the diagrams and following misunderstanding by others. We also consider different divisions by different people for the same diagrams with same parameters and different interpretations for the same terminology in the diagrams with different parameters. Both correct and incorrect data processing are discussed as well. The discussions and reviews show that complex and multiple systems of the igneous rock must be examined by more diagrams with different parameters in order to better determine the petrological characters. The correct understanding and application of the common igneous petrological diagrams and subsequent suggestions of “the unified platform for the research” may be useful for studying regional petrology.
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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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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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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.
