Editor in chief:YANG Wencai
Inauguration:
International standard number:ISSN 0371-5736
Unified domestic issue:CN 11-1952/p
Domestic postal code:2-382
- Most Read
- Most Cited
- Most Downloaded
2024, 70(3):0-0.
Abstract:
2024, 70(3):813-822. DOI: 10.16509/j.georeview.2024.04.021
Abstract:Classification of lead-zinc deposits is one of the mainest research subjects on lead-zinc ore geology. Methods:During the research and compilation of Annals of Geology of Mineral Resources in China——Lead and Zinc Mineral Resources, the writer carried out a more detailed survey, analysis and arrangement of the references related to classification of lead—zinc deposits in China and in the world, and suggested the host rock—genesis classification of lead—zinc deposits in China on the basis of studies on many important lead—zinc deposits in China and other countries. Results:The Chinese lead—zinc deposits have been classified into 11 types. The 11 types include sediment-hosted sedimentary—exhalative type, carbonate-hosted (epigenetic) type, sandstone lead and sandstone—conglomrate type, volcanic-hosted massive sulfide type, intrusion-related type, continental volcanic rock type, non-magmatic meso-epithermal type, non-sulfide type, placer type, composite type and superimposed type. Conclusions:The comprehensive (host rock + genesis) classification of lead—zinc deposits in China can cover the types, subtypes, styles and representative deposits of the whole country. Composite type and superimposed type are the characteristics of lead—zinc deposits in China, and the prospecting prospect of them is good, so the exploration and development and research of them should be strengthened.
YANG Minggui , CHEN Xiangyun , WU Junhua , ZHONG Cundi , WANG Yan
2024, 70(3):823-838. DOI: 10.16509/j.georeview.2024.04.061
Abstract:This paper gives a brief discussion on the Cathaysian Metallogenic Province with strategic mineral resources holding an important position, which was definited in the monograph of the “Mineral Geology of China: Tectonic Evolution and Mineralization in South China Ocean—Marginal Pacific Ocean” (2020): ① The Cathaysian Metallogenic Province is located in an extensive composite zone between the Paleo- South China Ocean Metallogenic Domain and the Marginal Pacific Metallogenic Domain, which underwent the development and evolution of the Early- Craton South China Ocean rift system epicontinental sea continent since the Early Precambrian. Furthermore, it was subjected to multiphase orogeny, especially the extremely extensive Yanshanian intracontinental activation orogeny, being the world- class tungsten geochemical block, which forms the superior metallogenic genetics. ② Major metallogenic characteristics: including South China Ocean and it’s metallogenic of marginal arc depression remnant, and the large- scale sedimentary metallogenitc during the Nanhua interglacial period and post- glacial period; multiphase and large- scale S- type magmatic metallogenic was predominated by the tungsten, secondly, nonferrous metal, uranium, precious metals and non- metallic; I- types magmatic mineralization is dominated by copper, with iron, nonferrous metals and precious metals, as well as the super- large ore concentrated group along the Qinzhou—Hangzhou metallogenic belt, which has become an “eye” for prospecting in the “deepth”, etc. ③ During the Yanshanian Movement, the magmatic and metallogenic “core—mantle” type spacial—temporal evolution regularity, as well as multi- system composite tectonic framework present the dynamic system, mainly due to the left- lateral shear between the continent and ocean with combination of ocean subduction, intracontinental multidirection convergence and crustal creep effect.
QIN Jinhua , WANG Denghong , WANG Yan , HUANG Fan , ZHAO Zhi , GUO Zhiqiang , ZHAO Chenhui , ZHAO Yunbiao
2024, 70(3):839-860. DOI: 10.16509/j.georeview.2024.04.075
Abstract:Nanling metallogenic belt is one of the most important and distinctive polymetallic, nonmetallic and energy mine metallogenic belts in South China and even in China. There is a long- term history of the study in metallogenic law, however each summary of achievements is greatly benefit for the new round of prospecting. Based on the abundant previous research data, the regional geology of the Nanling metallogenic belt are summarized in this study. The spatial and temporal distribution and metallogenic characteristics of critical energy minerals (coal and uranium), non- ferrous minerals (tungsten, tin, molybdenum, bismuth, copper, lead—zinc, etc.), precious metals (gold and silver), rare metals and rare earth minerals, non- metallic minerals (fluorite) are discussed in detail. Moreover, the mineral deposits in Nanling metallogenic belt can be divided into 21 metallogenic series and 29 sub- series according to the 6 tectonic epoches of Precambrian, Caledonian, Variscan, Indonisian, Yanshanian and Himalayan. Thus, it provides a basis for further regional mineral exploration deployment and metallogenic prediction. In order to ensure the security of energy and resources, this study proposed the principle opinions on the block transfer of Nanling metallogenic belt and suggestions on prospecting in 15 large- scale resource bases such as Shizhuyuan, Xianghualing, Chongyu, Fuhezhong, Pingbao and Sannan, which provide scientific guidance for new round of prospecting.
WANG Yan , WANG Denghong , QIN Jinhua , LI Hua , CHEN Zhenghui , GUO Naxin , HUANG Fan
2024, 70(3):861-873. DOI: 10.16509/j.georeview.2024.04.002
Abstract:The Metallogenic Regularity Map of Nanling Metallogenic Belt (1∶800 000) compiled and published by the Institute of Mineral Resources, Chines Academy of Geological Sciences, is the most complete, up- to- date and most informative metallogenic regularity map of the zone level (III metallogenic unit) that comprehensively reflects the exploration results and metallogenic regularity of Nanling in China. Results:The research and compilation of this map has achieved four major innovations: ① It covers 2903 independent mineral fields discovered in Nanling, including 76 minerals in four categories: energy, metal, non- metal and water—gas minerals, realizing the full coverage of minerals and mineral fields in the Nanling Metallogenic Belt; ② the strata of the geological base map are merged and diluted, highlighting the characteristics of the outcroped and covered intrusive rocks in South China, so that the distribution pattern of geological units of different tectonic and building layers is clear at a glance; ③ the five- in- one comprehensive legend design of mineral field, size, type, era and metallogenic series have been realized, and the expression of mineral field is more concise and intuitive; ④ synthesizing metallogenic series diagrams, tables, metallogenic system diagrams, profile diagrams and so on, and compiling new ideas and methods based on regional regularity maps, the latest scientific research achievements of the Nanling Metallogenic Belt are more concentrated to reflect and highlight the latest scientific research achievements. Conclusions:The research and compilation of this map is helpful to visually display the spatial and temporal distribution pattern of minerals in the Nanling Metallogenic Belt, summarize the metallogenic regularity in depth, and scientifically delineate important prospecting prospects, which is of great significance for comprehensively guiding the geological prospecting work of Nanling Metallogenic Belt.
ZHAO Chenhui , WANG Denghong , WANG Chenghui , YING Lijuan , QIN Yan
2024, 70(3):874-884. DOI: 10.16509/j.georeview.2024.04.012
Abstract:Sulfur isotopes are an important means to trace the source of mineralizing materials in mineral deposits, and they are also of reference significance for revealing the material cycle of sulfur.Methods: In this paper, we select 8 large and super- large copper deposits of different types, time and space in China, and systematically collect and organize 1415 sulfur isotope data.Results: ① Spatially, the sulfur isotope compositions of skarn- type, porphyry copper deposits and VMS copper deposits show a pattern of ‘top heavy and bottom light’ and ‘center light, edge heavy’. ② Temporally, the δ34S value of different ore types gradually increase from the early stage to the late stage of mineralization in the deposit scale. At the national scale, the δ34S values of chalcopyrite in different types of copper ores gradually decrease from early to late, which is contrary to the variation pattern at the deposit scale. ③ Indications for mineral exploration, the δ34S values of sulfide within the rich- ore bodies in the Jiama and Dabaoshan deposit are relatively positive, and the δ34S values of the pyrites near the mineralization center in the Ashele deposit are more negative, in addition, the δ34S values of co- rich pyrites in the early stage of the Hubi- type copper deposit are higher than the δ34S values of co- poor pyrites in the late stage. Conclusions:Expect for the Neoarchean Hongtoushan copper deposit, the δ34S values of chalcopyrite in different types of copper deposits significantly decrease from the Proterozoic to the Paleozoic to the Mesozoic and then to the Cenozoic, which is related to the evolution of the Earth.
LI Faqiao , TANG Juxing , SONG Yang , LIN Jun , LIN Bin , YANG Huanhuan , TANG Pan , ZHENG Ming , GUO Duoduo
2024, 70(3):885-906. DOI: 10.16509/j.georeview.2023.12.065
Abstract:The Naruo Cu (Au) deposit is currently the third biggest in the Duolong ore concentrated area in northwestern Xizang (Tibet). The study on chronology of petrogenesis an mineralization, metallogenic geological background, and so on, have been conducted comprehensively, but research on spatial alteration zoning and magmatic development process is quite limited. The apatite of the Naruo deposit serve as the study subject in this work. The study of apatite mineralogy and major elements geochemistry is carried out on the basis of a large number of drilling scientific research catalogs, and the colorful cathodoluminescence features of the apatite in the Naruo deposit are described. The coupling connection with alteration zone indicates the development stage of ore- bearing magma as well as the redox state change rule. The apatite in the Naruo deposit is mostly yellow—brown, green—bright yellow, and gray- black, correlating to unmodified magma, potassic alteration, and sericitization alteration, respectively. Those relationship validated the spatial alteration zoning structure of the “double potassic zone” of the Naruo deposit porphyry system, which was redefined in this work. The main element test results of apatite via EPMA show that CaO = 53.5%~56.5%, P2O5 = 39.5%~42%, F = 1.26%~3.24%, Cl = 0.01%~1.99%, SO3 = 0~1.28%, and the calculated XF= 0.68~1.76, XCl = 0.001~0.58, XOH = 0.21~1.05. The change trend of elements such as volatile components (F, Cl, OH) and SO3 of apatite in different types and stages reflects the process of gas saturation fluid exsolution metal precipitation in the magmatic hydrothermal evolution of the Naruo deposit, and reveals the nature of high oxygen fugacity of the ore- forming magma. In addition, the zonal magmatic apatite reflects that the cryptoexplosive breccia system has developed three stages of magmatism, and indicates that the I and III stages of magmatism are characterized by high oxygen fugacity, which are more closely related to mineralization. This paper therefore holds that the multiphase magmatic hydrothermal alteration superimposed porphyry copper deposits can also benefit greatly from apatite inversion of the magmatic hydrothermal evolution process and auxiliary determination of alteration zoning in addition to the concealed porphyry copper deposits in the till covered area.
CHEN Xu , FAN Honghai , HE Debao , CHEN Jinyong , GENG Ruirui , CHEN Donghuan , WANG Yongjian
2024, 70(3):907-923. DOI: 10.16509/j.georeview.2024.03.015
Abstract:The Rossing deposit is a world- class alaskite- type uranium deposit, with multiple mineralization zones such as SJ, SH, SK, Z17, and Z19. There are significant differences in mineral combinations among these zones, but the level of systematic mineralogical research is not high. Methods: This work systematically studied the symbiotic combination and occurrence status of uranium minerals in the main ore (mineralization) zones of the Rossing area through methods such as rock—mineral determination, scanning electron microscopy observation, and electron probe analysis. Results: The results show that the mineralization of alaskite mineralization can be divided into three categories based on mineral assemblages: ① uraninite + zircon + apatite combination, mainly distributed in the Z17, Z19, and SJ areas; ② coffinite, uranothorite +sphene+ apatite combination, mainly found in the SH area; ③ betafite combination, mainly distributed in the SK and SH areas. Conclusions: The uranium mineralization in the study area can be divided into three stages: magmatic stage, hydrothermal stage, and epigenetic leaching stage. The magmatic stage is the primary ore- forming stage, the electron probe chemical age of uraninite in the study area is 505±11 Ma, representing the magmatic mineralization age. In the SH area, further exploration should focus on finding coffinite, uranothorite +sphene+ apatite combination in mineralized alaskite.
2024, 70(3):924-931. DOI: 10.16509/j.georeview.2024.04.015
Abstract:n the No. 6 of Vol. 69 of GEOLOGICAL REVIEW, an article authored by LI Boyun and five others from the brine exploration standard drafting team is published. The title of the article is “On the applicability of the current salt lake brine deposit exploration specifications——Discussion with Mr. QIAN Xuepu”. The article argues that “the current brine exploration standard, overall, is an applicable standard and no major issues have been identified”. However, writer believes that the standard drafting team erroneously treats brine as a solid mineral, requiring geological exploration methods for solid minerals, and conducting construction with dozens or hundreds of geological holes to determine the geological reserves of brine. This approach is deemed extremely flawed. The implementation of the current brine exploration standard has led to significant economic losses and stifled the development of deep brine. Currently, this thoroughly flawed standard urgently needs revision. The author proposes a Summary of Geological Exploration for Brine Minerals for reference in the revision of the standard.
WANG Zhenghe , ZHANG Ronghu , YUE Yong , YU Chaofeng , YANG Zhao , ZHI Fengqin
2024, 70(3):932-944. DOI: 10.16509/j.georeview.2024.01.012
Abstract:The third- order sequence division of the Lower Silurian Kepingtage Formation in the Tarim Basin was different based on different research locations or areas, which restricted the understanding of the regional tectonic—sedimentary evolution and the direction of oil and gas exploration of these strata. So it is necessary to analysis the sedimentary characteristics and divide the third- order sequence of these strata again.Methods: In order to reasonably divide its third- order sequence, we have combined with all data of outcrops, published wells and seismic, existing research results, the detailed analysis of the sedimentary and sequence characteristics of the outcrop of the Kepingtage Formation in Aqia area, Keping County.Results: ① The Kepingtage Formation in Aqa area is mainly a delta sedimentary system controlled by mixed hydrodynamics dominated. From bottom to top, the lower member is a sedimentary cycle from fining- up to coarsing- up, and the middle and upper members form a coarse- up sedimentary cycle as a whole. ② The unconformity surfaces at the top, bottom and inside of the Kepingtage Formation can divide it into two third- order sequences. The lower member constitutes SQ1, with LST, TST and HST. The middle and upper members constitute SQ2, with only TST and HST.③ The boundary between the middle and the lower members of the Kepingtage Formation may correspond to the unconformity formed by the sea level decline during the glacial period in the Late Ordovician Hernantian.④ As the hydrodynamic conditions of different system tracts are different, the LST is dominated by river effect, while the wave and tide effect is greater than the river effect in HST. ⑤ TST in SQ2 is a regional high- quality cap rock, which can form a good cap-reservoir combination with HST in SQ1. Therefore, HST of SQ1 in the western Awati sag can be the primary exploration target in this strata.Conclusions:In Aqia area, the Kepingtage Formation belongs to a delta sedimentary system formed with the mixed hydrodynamics, and it can be divided into two third- order sequences. The study has a new significance for oil and gas exploration about these strata.
WANG Zhenyi , ZHANG Jin , WU Chunjiao , ZHAO Heng , ZHANG Beihang , ZHANG Yiping
2024, 70(3):945-959. DOI: 10.16509/j.georeview.2024.03.001
Abstract:Many Precambrian geological units remained in the orogenic belt; some of them were considered as the Precambrian basements for discussing the tectonic affinities of the microcontinents they belonged to. Because the nature of the microcontinents is of great significance to the architecture and evolution of the orogenic belt, and the Precambrian geological units discussed contain information about the early evolution history of Earth, the definition of the nature of the microcontinent has become one of the key and difficult issues in the study of the orogenic belt. This study takes the microcontinents of the middle segment of the southern Central Asian Orogenic Belt as an example to summarize and sort out the criteria for defining the nature of microcontinents: rock assemblages, metamorphism and deformation, the age feature of provenance revealed by detrital zircon spectra, geological event sequences, the Precambrian crustal evolution characteristic indicated by Hf or Nd isotopes, deep crust information denoted by inherited zircons or zircon xenocrysts and the isotopic composition of Paleozoic igneous rocks, and geophysical characteristics. The different criteria for defining the nature of microcontinents, even the same criterion, lead to huge controversies over it, which affects the understanding of the tectonics and evolution of orogenic belts. Based on the above reasons, this paper suggests that the discussion on the affinity of the Precambrian basement should not only focus on the rock assemblages and formation age but also pay attention to the comprehensive comparative analysis of its metamorphism and deformation characteristics, contact relationships, provenance age characteristics, rock genesis and tectonic setting, crustal accretion information, and deep crustal information on the basis of elaborate field anatomy and high- resolution geochronology, so as to obtain more comprehensive criteria and explore its tectonic affinity. When a series of information of Precambrian geological units are obtained, they can be compared with the same tectonic unit first and then with other units. When the characteristics are different, it is necessary to split the tectonic unit or consider the possibility of structural emplacement (including but not limited to thrusted, strike slipped allochthons, and subduction scraped tectonic slices); When the characteristics are similar, it may indicate that the same microcontinent has been broken up or different microcontinents have experienced similar Precambrian history.
LIU Chuanzheng , LIANG Kuan , WANG Xiuying
2024, 70(3):960-974. DOI: 10.16509/j.georeview.2024.04.011
Abstract:At 23∶59′, December 18, 2023, a Ms6. 2- magnitude earthquake occurred in Jishishan County, Gansu Province. The major axis of the extreme earthquake was in the direction of NNW, with a maximum intensity of Ⅷ and a maximum ground acceleration of 1. 0 g. About 15×104 m2 of liquefaction collapse occurred on the headwater platform of Dashagou basin, Zhongchuan Township, Minhe County, Qinghai Province, 20 km from the epicenter. The active water and soil volume was about 60×104 m3, and about 45×104 m3 of soil side flow entered the gully, impacting the gully from north to south to form a disaster chain, and accumulated about 30×104 m3 in Caotan—Jintian Village, resulting in 20 fatalities.Objectives: The study of liquefaction and lateral flow of seismic sand is not only a scientific problem related to the formation mechanism of geological disasters, but also a realistic problem that must be faced in formulating practical disaster prevention and reduction countermeasures. This study is to clarify the formation factors, dynamic mechanism and movement characteristics of soil flow disaster chain, and provide a basis for preventing and coping with similar geological disasters.Methods: By using the methods of field investigation, interview, satellite remote sensing and UAV image interpretation, water content measurement, analysis and description, and calculation, the author has carried out the zoning of the soil flow disaster chain in Dashagou basin, and tried to obtain the scientific understanding combining qualitative and quantitative.Results: The distribution length of the disaster chain of soil flow in Dashagou basinis about 3. 1 km, which can be divided into five parts: soil liquefaction loss area, soil flow obstructing and returning silt area, roadbed blocking impact area, soil overpiling and buried area, and mud flood area. From upstream to downstream, it causes damage to cultivated land, collapse of electric tower, destruction of irrigation channel, destruction of village road, burying of township road, burying of personnel house, and silting of Yellow River diversion irrigation channel. The soil flow has a transitional ternary layered structure, including the ice water layer at the bottom, the mud flow layer in the middle and the wet soil layer at the top. The movement time from the start of the liquefaction soil to the buried pressure of Caotan—Jintian Village was less than 10 min, the time from the start of the soil flow to the roadbed collapse of Meiyi Village was about 4. 38 min, and the time from the arrival of Caotan—Jintian Village was about 6. 15 min, resulting in the Caotan—Jintian Village disaster within the following 3. 5 min.Conclutions: The formation of the disaster chain of soil flow in Dashagou basin is both inevitable and accidental. It is a rare geological disaster chain that includes the damaged land in the starting area, the electric tower, the roadbed blocking in the circulation area, and the sedimental area——The dwellings and irrigation channels in Caotan—Jintian Village. The formation of soil- flow disaster chain is the result of the overlapping of many factors such as geology, water source, dynamics, topography and disaster bearing bodies, including thick silty soil, high groundwater, strong ground motion, gentle terrain inclined to gully outlet, roadbed blocking energy storage outburst and multiple disaster bearing bodies along the way. The dynamic effects of soil flow in the gentle channel include soil liquefaction in the starting area, gate beam flow in the channel, subgrade collapse across the channel, ice water lubrication in the channel, water and soil train accumulation in the village and earthquake stress and panic of the victims. The village dwellings were built on the alluvial beach of Dashagou baisin, which virtually increased the risk of disaster and the difficulty of independent prevention.Countermeasures: Some suggestions are put out in this paper that consists of to carry out disaster prevention and mitigation training, prevent the risk of geological disasters, change farmland irrigation to drip irrigation, urban and rural communities to build sites to avoid flood plain or floodplain, dredging rivers to widen the cross section, soil flow initiation area to carry out land readjustment and soil and water conservation.
ZHONG Yongsheng , LI Jingbo , WANG Guohong , YAN Zhaokun , ZHOU Jiqian , WANG Duofu , ZHENG Liangzhong , ZHANG Juyuan , WU Mingliang
2024, 70(3):975-995. DOI: 10.16509/j.georeview.2024.03.031
Abstract:In order to explore the seismogenic structure of the 2022 Luding magnitude 6. 8 earthquake and the migration patterns of strong earthquakes in the Xianshuihe fault zone. Methods: Based on existing literature and field geological surveys in the southern section of the Xianshuihe Fault Zone, this paper statistics the slip rate and historical earthquake data, and summarizes the migration patterns of strong earthquakes in the Xianshuihe Fault Zone in modern times, which is helpful for understanding the activities of the Xianshuihe Fault Zone. Characteristics and future seismic risk are of great significance. Results: The sliding rates of each section of the Xianshuihe fault zone are quite different; the seismogenic structure of the Luding earthquake was a left- lateral strike- slip event; the active period of strong earthquakes in the Sichuan—Yunnan region in modern history has the characteristics of “jumping” migration;Conclusions: ① The sliding rates of each section of the Xianshuihe fault zone are quite different. With Qianning as the boundary, the section from NW to SE shows a sliding characteristic of “first decelerating and then accelerating”. ② The seismogenic structure of the Luding earthquake The Moxi fault is a left- lateral strike- slip event. ③ The active period of strong earthquakes in the Sichuan and Yunnan regions in modern history has the characteristics of “jumping” migration. After the Daofu earthquake in 1981, the Xianshuihe fault zone entered a relatively quiet period, which lasted for 33 years. Since the Kangding earthquake in 2014, the Xianshuihe fault zone has once again entered a seismically active period. ④ The strong earthquake rupture of the Xianshuihe fault zone is not a “through- type” pattern of a single earthquake, but a gradual pattern of multiple earthquakes. The interaction between faults, especially the occurrence of large earthquakes, has a significant impact on the recurrence interval of strong earthquakes in the fault zone. Strong earthquakes in the same fault zone will also change the probability of subsequent earthquakes.
CHEN Xianting , DONG Peipei , LI Yingjie , MENG Guang’an , LIN Min , WANG Shuai , ZHAO Dongfang , LIU Jingjing , LIU Zhibin
2024, 70(3):996-1012. DOI: 10.16509/j.georeview.2024.03.022
Abstract:Based on 1∶50000 regional geological survey, the field geological characteristics, petrology, geochemistry and zircon U-Pb chronology of the volcanic rocks of the Upper Jurassic Manitu Formation in Chabuqiri area, Inner Mongolia, central-south Great Hinggan Mountains, were systematically studied by using the triple mapping method of “volcanic structural—litho—lithofacies and volcanic stratigraphy”. The Manitu Formation in Chabuqiri area of Inner Mongolia is divided into two lithologic members. The First Member consists of pyroclastic sedimentary rocks with a small amount of neutral and moderately acidic pyroclastic rocks, and the Second Member consists of neutral lava, pyroclastic rocks with a small amount of pyroclastic sedimentary rocks and acidic pyroclastic rocks, forming a complete sediment-eruption cycle. The volcanic facies are divided into eruption-sedimentary facies, excrete facies, clastic flow accumulation facies, void fall accumulation facies and volcanic channels, and four Ⅴ-class volcanic edifices are outlined. The LA-ICP-MS U-Pb age of the zircons from the andesite in the Second Member of the Manitu Formation in Chabuqiri-manitu Formation is 157. 8±1. 4 Ma, indicating that it was formed in the Late Jurassic. The geochemical characteristics of the trachyandensite in the Second Member of the Manitu Formation are: SiO2= 64. 04%~65. 40%, high Al2O3(16. 02%~16. 96%), rich alkali (K2O+Na2O=8. 07%~8. 38%), low Fe2O3(3. 12%~3. 96%), poor TiO2(0. 6%~0. 81%), A/CNK values between 1. 02~1. 12; the REE ranges from 177. 6×10-6 to 254. 6×10-6, with obvious differentiation between light and heavy rare earth, (La/Yb)N=8. 13~12. 63, and a weak negative Eu anomaly (δEu= 0. 71~0. 78); the trace elements are characterized by rich large ion lithophile elements (Rb, Ba, Th, U, K) and relatively deficient high field strength elements (Nb, Ta, P, Ti). The geochemical characteristics of main elements and trace elements show that the trachyandensite of the Second Member of the Manitu Formation in Chabuqi area is shoshonitic series rock. The volcanic magma of the Manitu Formation in Chabuqi area originates from the partial melting of the continental lithospheric mantle triggered by extensional process, and is less affected by crustal mixing, which may have formed in the extensional tectonic setting after the Mongolian-Okhotsk Ocean orogeny.
LIU Jingjing , LI Yingjie , LIN Min , YAO Hailong , ZHAO Dongfang , CHEN Xianting , LIU Zhibin
2024, 70(3):1013-1029. DOI: 10.16509/j.georeview.2023.12.045
Abstract:Aiming at the problems such as chaotic stratigraphic division, unclear evolution background, volcanic stratigraphic sequence and weak research on volcanic mechanism of Baiyingaolao Formation, this paper takes the volcanic rocks of the Baiyingaolao Formation developed in Sanjie Aobao area, East Ujimqin Banner as the research object, based on 1∶50000 regional geological survey and the triple mapping method of "volcanic structure, lithology, lithofacies and volcanic stratigraphy". It can be divided into three lithologic segments which constitute the complete sedimentation—eruption cycle: pyroclastic sedimentary rocks, acidic volcanic rocks and neutral volcanic rocks. The magma evolved from acidic to neutral from early to late period. Volcanic sedimentary facies, cave- down accumulation facies, overflow facies and volcanic channels were developed, and six V- class volcanic structures were delineated. Based on LA- ICP- MS zircon U- Pb isotope dating, it is determined that the second member rhyolite of Baiyingaolao Formation in Sanjie Aobo area was formed in 135. 0±1. 0 Ma, and the age is Early Cretaceous. Geochemical characteristics show that the main element SiO2 content ranges from 69. 56% to 71. 11%, K2O content ranges from 3. 96% to 4. 39%, K2O/Na2O value ranges from 0. 69 to 1. 03, and A/CNK value ranges from 0. 97 to 1. 07. The volcanic rocks of the Baiyingaolao Formation in Sanjie Aobo area belong to the high potassium calc- alkaline series. Rb, K, Th, U are relatively enriched, Sr, Ti, Nb, Ta, P are relatively depleted, and the difference of heavy and heavy rare earths is obvious, and the former is higher than the latter, and the standardized partition curve of rare earth elements chondrites shows A right- leaning “seagull”, which conforms to the geochemical characteristics of A- type granite. Combined with previous studies and data analysis, the volcanic rocks of the Baiyingaolao Formation in Sanjie Aobao should be formed in the post- orogenic extensional tectonic environment. Therefore, the determination of the volcanic rocks of the Baiyingaolao Formation in this study area provides petrological, chronological and geochemical constraints on the stratigraphic sequence and tectonic setting of the Mesozoic volcanic rocks in the eastern part of the Central Asian orogenic belt.Methods: Based on field geological characteristics, LA- ICP- MS zircon U- Pb chronology and geochemistry, the volcanic eruption rhythm, volcanic mechanism characteristics, petrogenesis and tectonic setting of the Baiyingaolao Formation volcanic rocks in Sanjie Aobao area are discussed.Results:(1) The volcanic rocks of the Baiyingaolao Formation in Sanjie Aobao area are divided into three lithologic segments which can form a complete sedimentation—eruption cycle: Member 1, Member 2 and Member 3. The early to late magmas are characterized by the reverse evolution from acidic to neutral. By using the mapping method of "volcanic tectonic—litho—lithofacies — volcanic strata", the volcanic facies, including volcanic sedimentary facies, void deposition facies, overflow phase and volcanic channel, are divided into six V- class volcanic structures.(2) The zircon U- Pb age of theSecond Member of the Baiyingaolao Formation is 135. 0±1. 0 Ma, indicating that the rhyolite was formed in the Early Cretaceous.(3) The rhyolite of the Second Member of the Baiyingaolao Formation has the characteristics of A2- type granite, indicating that the formation of the Early Cretaceous volcanic rocks is related to the extensional tectonic environment of the closing and post- closing of the Mongolia—Okhotsk Ocean.Conclusions: It is confirmed that the volcanic rocks of the Baiyingaozao Formation in Sanjie Aobo area were formed in the Early Cretaceous (135. 0±1. 0 Ma), and are related to the extensional tectonic environment after the Mongolia—Okhotsk Ocean closed orogeny. Volcanic facies such as volcanic sedimentary facies, cave- down accumulation phase, overflow phase and volcanic channel were divided, and six V- level volcanic institutions.
2024, 70(3):1029-1030.
Abstract:近日,经单位推荐、形式审查、初审、审定和公示等程序,遴选产生了中国地质学会2023年度“地质科技重要进展、地质找矿重大成果”项目(附表1、表2)
LI Chunjia , ZHANG Hongrui , LUO Dike , JIN Lijie , GAO Jilei , WANG Zisheng , LIANG Yunhan , JIA Pengfei , LIU Wei , ZHANG Pan
2024, 70(3):1031-1046. DOI: 10.16509/j.georeview.2023.12.002
Abstract:The sedimentary age, material source, sedimentary environment and tectonic setting of the arkose of Inkisi Formation in northeast Angola are discussed through detritonal zircon dating and petrogeochemistry, which provide scientific basis for the study of the evolution of Congo Basin.Methods: We performed the zircon LA-ICP-MS U-Pb isotopic dating, major elements and trace elements compositions of the arkose from Inkisi Formation in northeastern of Angola. Results:The results show that the 206Pb/238 U age of detrital zircon is mainly concentrated in three peak age ranges of 2350~1900 Ma, 1150~850 Ma, and 850~500 Ma, with the youngest zircon having a peak age of 531±9 Ma.Conclusions: The upper limit of depositional age of Inkisi Formation in this area is the Early Cambrian. The geochemical characteristics of the sandstone of Inkisi Formation show that the provenance has the characteristics of near- source transport of felsic provenance, and the water in the sedimentary period was an open freshwater environment of continental facies. Based on the age spectrum of detrital zircon, source identification of major trace elements and structure identification diagram, the results show that the West Congo tectonic zone is the main provenance zone, followed by the Lufilian tectonic zone and Angola shield. The tectonic environment of its provenance area is mainly active continental margin and passive continental margin tectonic environment background.
WANG Haonan , ZHANG Changmin , SUN Jiahui , ZHANG Xianghui , XU Qinghai , LIU Hongping , Adrian John HARTLEY
2024, 70(3):1047-1060. DOI: 10.16509/j.georeview.2023.11.002
Abstract:To explore the river network distribution of distributive fluvial systems, and to provide knowledge base information for creating reservoir modeling training images. Methods: Using modern geographic information software tools such as Google Earth, Global Mapper, and 91 Satellite Map Assistant, the surface river channel bifurcation characteristics of the modern Golmud Fluvial Fan were systematically measured. The river network pattern model of the fluvial fan was established using Horton's law and fractal methods.Results:The results show that: ① The Golmud River Fan has identified 26 river channels from the apex to the lake inlet section, 882 nodes and 2162 river sections. The river channels along the spring line and below show different river network patterns; ② There are a total of 64 nodes developed in the upper part of the spring line, with an increase of RB=1.8900 times the number of rivers in each level compared to the previous level, and an average length of RL=1.0095 times that of the next level, indicating that the characteristic parameters of river network morphology are RB=1.8900 and RL=1.0095; There are a total of 818 nodes developed in the lower part of the spring line, with an increase of RB=1.0279 times the number of rivers in each level compared to the previous level. The average length of each level of river is RL=0.9899 times that of the next level of river, which means that the characteristic parameters of river network morphology are RB=1.0279 and RL=0.9899; ③ The characteristic parameters of river network morphology vary greatly due to the influence of slope. If the slope is larger, the characteristic parameters of river network morphology are larger, and if the slope is smaller, the characteristic parameters of river network morphology are smaller. Conclusions:The quantitative characterization of river network pattern characteristic parameters has promoted the development of sedimentology in distributive fluvial systems, providing new knowledge base information for conducting reservoir modeling and sand body prediction in continental basins.
FENG Xukui , CHEN Youzhi , ZANG Dianguang , LI Mingjie , WU Furong , LIANG Hong , YANG Xiao , GUO Haiyang , ZHAO Zhenwei
2024, 70(3):1061-1070. DOI: 10.16509/j.georeview.2023.11.021
Abstract:Geophysical data show that there are thrusts deep under the salt-rock layer of the Cambrian Gaotai Formation near Qiyue Mountain in the eastern margin of Sichuan Basin, the formation process of the thrusts and the geological significance of oil and gas have not been deeply studied.Methods: Based on the swath 3D and two-dimensional seismic reflection data in Shizhu and Jiannan area of eastern Sichuan Basin, combined with drilling datas and regional geological research results. Results: ① The tectonic deformation of the northern Qiyue Mountains in eastern Sichuan is strong, and the basement involved structure is widely developed. The structural style is controlled by the tectonic location of the Qingbaikou-Nanhua rift and transition belt. ② According to the structural inheritance relationship, Dengying Formation platform boundary belt can be divided into Deyang-Anyue primary type platform boundary belt, Wanyuan-Dazhou inherited type platform boundary belt and Shizhu inheritance-modified type platform boundary belt. ③ Based on the distribution of Qingbaikou-Nanhua rift and the influence of late tectonics, it is believed that there are inheritance-modified platform margin belts of Dengying Formation similar to Shizhu area along Qiyue Mountain southward to Nanchuan, and there are inheritance-modified platform margin belts of Dengying Formation in Zhongxian and the west of Nanchuan. ④ A complete reservoir-cap association is formed by Neoproterozoic Lower Cambrian source rock, Dengying Formation and Longwangmiao Formation beach facies dolomite reservoir and Cambrian salt-rock layer in the study area. ⑤ The pre-salt basement thrusts of Cambrian can form rows and belts, and the fault-related tectonic-lithologic trap with Dengying Formation's succinction-reformed platform margin belt and Longwangmiao Formation's shoal facies dolomite reservoir configuration has become a favorable area for oil and gas accumulation in east Sichuan.Conclusions: The Sinian-Early Cambrian in Shizhu area of eastern Sichuan Basin inherited the characteristics of Qingbaikou-Nanhua rift, while the Yanshanian tectonic inversion. The formation of the basement involved thrust structure under salt in the Gaotai Formation, which has the basic petroleum geological conditions such as reservoir cap, and has important practical significance for oil and gas exploration.
SHANG Chunjiang , KANG Yongshang , YUAN Xiaoqiang , DENG Ze , ZHAO Qun , WANG Hongyan
2024, 70(3):1071-1082. DOI: 10.16509/j.georeview.2023.11.011
Abstract:The vertical mineral combination of shale formations varies greatly, and shale gas exploitation requires large- scale artificial hydraulic fracturing. During the fracturing transformation of shale gas exploitation reservoir, the regularity and mechanism of permeability change are of great significance to the design of fracturing engineering of shale gas. Methods: The author and others conducted fluid—solid coupling physical experiments on three shale samples with different mineral combinations based on the whole- rock X- ray diffraction analysis of samples. Results: Shales with different rock and mineral compositions exhibit different characteristics of microfractures and permeability changes under different conditions. Both siliceous and carbonate minerals can be used as brittle minerals, but there are significant differences in their brittleness characteristics. Conclusions: Based on the comprehensive analysis, three insights were obtained: ① During the loading process, the presence of small stress platforms in the stress—strain curve can indicate the formation of micro- fractures in the sample, which is the intrinsic mechanism of permeability change; ② The permeability of different mineral combination shale samples varies significantly with the axial pressure. The essence is the combination of minerals, and the brittleness of shale samples is different. During the pressurization process, the development of fractures is different, resulting in different permeability changes; ③ Rickman's mechanical brittleness index can only better reflect the brittleness characteristics determined by siliceous minerals. While when the content of carbonate minerals (calcite) is high, Rickman's mechanical brittleness index is difficult to effectively reflect the brittleness characteristics.
2024, 70(3):1083-1096. DOI: 10.16509/j.georeview.2024.04.001
Abstract:In order to select the optimal geological suitability evaluation model of underground space resources, realize scientific and reasonable evaluation of underground space resources, and provide reasonable planning support for underground space development. In this paper, three different models are selected for comparative analysis, and their advantages, disadvantages and applicable conditions are summarized, and the geological suitability evaluation of underground space resources is evaluated by taking Nanshan District of Shenzhen as an example, and the zoning map of geological suitability evaluation of underground space resources in Nanshan District is generated by ArcGIS. The evaluation results show that the evaluation model of the most unfavorable grade discrimination method is more suitable for the geological suitability evaluation of Nanshan District, highlighting the restrictive effect of sensitive factors on the development of underground space in Nanshan District. This paper has a certain reference significance for the future model selection of geological suitability evaluation of underground space resources, and provides a certain reference for the planning of underground space in Nanshan District, Shenzhen City.
XU Danni , SONG Wenlei , YANG Jinkun , CHEN Qian , LIU Taotao , XU Yitong
2024, 70(3):1097-1112. DOI: 10.16509/j.georeview.2023.11.085
Abstract:Carbonatite- type rare earth elements (REE) deposits are the primary source of REE in the world. Phosphate is a common component in this mineralization system, but there is still a lack of systematic understanding of its role in the REE mineralization process of carbonatite. This article reviews the role of phosphate in the origin, evolution, and REE enrichment of the carbonatites and proposes current problems and research prospects. Phosphorus has a very high solubility in the carbonate melt. The presence of phosphorus is conducive to the preferential partitioning of REE into carbonate melt during the extremely low- degree mantle partial melting process and the carbonate—silicate liquid immiscibility process, therefore forming a pre- enrichment of REE in the initial carbonatitic melt. During the evolution of carbonatite magma, REE will preferentially enter immiscible phosphate melts or phosphate minerals such as monazite and apatite. The behavior of these melts and minerals is likely to be a key factor controlling REE's behavior and mineralization potential in the system. The REE- rich phosphate mineral formed during the magmatic stage can also be a source of REE mineralization in hydrothermal processes. Phosphate mineral is also an effective precipitator for REE in the hydrothermal process, which is conducive to mineralizing light and heavy REE in the late hydrothermal fluid stage. In the future, more attention should be paid to the role of phosphate in the evolution of the carbonatitic magmatic stage and the enrichment mechanism of heavy REE in this system, and experimental petrology and melt inclusion studies should be carried out for specific mineralization processes.
2024, 70(3):1113-1120. DOI: 10.16509/j.georeview.2023.12.035
Abstract:The participation of geoscientists in science popularization plays a crucial role in advancing the development of geology, enhancing the quality of science popularization, and contributing to economic and social progress. According to survey, most geoscientists recognized the significance and impact of science outreach and were eager to engage in such activities. However, challenges such as insufficient support, limited dissemination channels, superficial content, and uneven capabilities in science popularization are notably prominent. Key strategies to encourage geoscientists' participation in science outreach include enhancing the awareness of science popularization responsibilities within geological research institutions, reinforcing the roles of related scientific associations and societies, bolstering systems for promotion incentives, rewards, and evaluations, expanding training in geological science popularization skills, and fostering experience sharing. Guiding geoscientists to improve their abilities in public science outreach is crucial for promoting their involvement in this field.
YANG Gaoxue , CAO Ruiming , GUO Xiangmin , CUI Wei , LIU Chunlai , YANG Liqun , DING Feng
2024, 70(3):1120-1126. DOI: 10.16509/j.georeview.2024.05.045
Abstract:The Sijiaying banded iron formation (BIF)- type iron ore is the largest iron deposit in eastern Hebei, for which a great deal of chronological, petrological, and elemental geochemical work has been carried out, but no Fe isotope study has yet been done. Methods:This article proposes effective constraints on the ore- forming material sources and formation background of Sijiaying BIF through the combination of Fe isotopes, major elements, trace elements, and rare earth elements. At the same time, it supplements the zircon U- Pb age data of Sijiaying BIF. Results:Zircon U- Pb geochronology shows that the Sijiaying BIF was formed at 2537~2531 Ma. Geochemical data shows that Sijiaying BIF ore is mainly composed of TFe2O3 and SiO2, with lower Al2O3 and TiO2 contents and enriched in Fe heavy isotopes (δ56Fe=0.341‰~0.525‰); the rare earth element distribution pattern shows the characteristics of light rare earth depletion and heavy rare earth enrichment, with obvious positive anomalies of Eu, Y, La, and high Y/Ho ratio (Y/Ho=34.96~45.84).Conclusions:These characteristics indicate that Sijiaying BIF is a chemically sedimentary rock with minimal involvement of detrital materials. Rare earth elements are derived from a mixed solution of high- temperature hydrothermal and seawater, while iron is derived from marine hydrothermal fluids. The lack of true negative Ce anomalies and positive Fe isotope compositions in Sijiaying BIF indicates that it was formed in an hypoxic environment. By comprehensively comparing the Fe isotope characteristics of the Archean BIF in other regions of the world, this article believes that the oxygen content in the Earth's oceans gradually increased during the Neoarchean period. At this time, the oceans generally belonged to an anaerobic environment, but some areas had higher oxygen content.
WANG Deyuan , Jean BOTTAZZI , ZHOU Wenlong , LI Wei , HU Wanmei , LV Xiaoxi
2024, 70(3):1121-1126. DOI: 10.16509/j.georeview.2024.01.032
Abstract:The giant panda was widely distributed in South China during the Late Pleistocene, with numerous fossil sites, but relatively few intact skeletal materials. We report the newly discovered complete giant panda skull fossil in Yangtianwo Shaft, Huishui, Guizhou, and analyze its burial characteristics combined with cave features.Methods: We have carried out detailed cave survey and cave mapping of Yangtianwao—Baima Cave system. The teeth of giant panda were studied in detail by morphological measurement and compared with those of Ailuropoda melanoleuca baconi and modern giant pandas (Ailuropoda). The fractured bone fragments were dated by AMS—14C dating method.Results: There are favorable conditions for the preservation of fossil in the Yangtianwo Shaft — Baima Cave system because of its special cave environment. According to the measured data, the teeth of Yangtianwo giant panda are slightly larger than those of modern giant pandas, and should belong to the Ailuropoda melanoleuca baconi. The AMS—14 C dating results are 22887~22431 a BP, which is around the last glacial maximum.Conclusions: The discovery of new materials provides rare physical evidence for the distribution range, survival and evolution of giant pandas at the end of the late Pleistocene.
BAI Chundong , XU Fan , LI Zeyang , MENG Jiabao , ZHU Benhong
2024, 70(3):1127-1138. DOI: 10.16509/j.georeview.2023.11.055
Abstract:This paper is the result of geological survey. Writers first discovered the basalt association at the bottom of the Middle—Upper Jurassic Tiaojishan Formation in the Xuanhua District—Zhuolu County area, Zhangjiakou City, whose age, geochemical properties, and geological significance requires to further research. This article conducts geological, petrological, geochemical, and isotopic chronological studies on the basalts. The SiO2 content of the basalt ranges from 39. 49% to 49. 74%, Mg # ranges from 28 to 65, and the Rittmann index (σ) ranging from 2. 61 to 33. 12. The basalt belongs to the alkaline basalt series and forms bimodal volcanic rock combination with the overlying trachyte, indicating that the early volcanic rocks of the Tiaojishan Formation were formed in a continental plate tensile environment. This set of basalts is a geological, petrological, and tectonic study of the basaltic magma underplating of the neutral volcanic rocks of the Tiaojishan Formation.
SHI Qiang , MA Long , CHEN Xiangzhi , XU Zhongyuan , LI Shichao , XU Jingui , CHEN Kaiyun
2024, 70(3):1139-1144. DOI: 10.16509/j.georeview.2023.11.035
Abstract:In China, the early Precambrian basement of the Western block is widely distributed on the northern margin of the North China Craton. Previous study generally suggests that these old rock was influenced by four metamorphic thermal events at ca.2.5 Ga, ca.2.45~2.37 Ga, ca.1.95 Ga and ca.1.85 Ga. The study of the ca.2.5 Ga charnockite from the Yinshan Block which has become a hot topic in revealing the early Precambrian tectonic evolution of on the northern margin of the North China Craton, however, there are few reports of late Neoarchean tectonic thermal events in the Khondalite Belt. In recent years, a stage of Daqing Mountains supracrustal rock, with a metamorphic zircon age at 2.45~2.37 Ga, has been identified from the Khondalite Belt (eg. Garnet biotite gneiss) of the Daqing Mountains area. In field, the Daqing Mountains supracrustal rock and anatectic garnet granite are closely related to each other, however, the mode of its anatectic genesis is still controversial. Herein, we present new geochronological of zircon U- Pb isotopic data via analysis using a sensitive high- resolution ion microprobe for charnockites, and comparing the field spatial output relationship and zircon chronologyits analysis to the garnet granite and its surrounding rocks in the Daqing Mountains terrane. Our aims are to provide the important insights for exploring the genetic model of anatectic garnet granite.
HU Hewei , XU Peng , YU Haibo , LIAN Haojie , JI Xinyuan , DING Yiran , SHAO Longyi
2024, 70(3):1145-1158. DOI: 10.16509/j.georeview.2024.02.011
Abstract:The sandstone reservoirs of the braided river delta facies are developed in the 2nd Member of the Paleogene Shahejie Formation (Sha- 2 Member) in the steep slope zone of the Shanan Sag, the Bohai Bay Basin. The reservoir is influenced by structural location, burial rate, paleotemperature changes, and faulting, and its physical properties vary significantly in different structural areas, especially in the middle—deep layers. In this paper, the sedimentary facies, diagenesis, and pore evolution characteristics of the middle—deep sandstone reservoirs are studied by using the data of drilling, logging, seismic, and laboratory analysis, and the main controlling factors and evolution regularities of the high- quality reservoirs are proposed. The results show that the middle—deep sandstones in the study area are mainly lithic arkose, and the pore spaces are mainly intergranular dissolved pores. There are four types of reservoirs, i.e., the medium porosity—medium permeability type, the medium porosity—low permeability type, the low porosity—low permeability type, and the low porosity—ultra- low permeability type. The medium porosity—medium permeability type is the main one in the area. The pore space of the reservoir is generally well developed, being characterized by a medium porosity and a medium permeability, supporting a good physical property. Further investigation has revealed the major controlling factors of the high- quality reservoirs. The provenance rock rich in quartz and feldspar is the material foundation, the delta plain distributary channel is the favorable sedimentary facies type, and the strong dissolution of calcite cement during the late diagenesis provides major pore space, all of which play the key role in the development of the high- quality reservoir. The analysis of the spatio—temporal distribution of the high quality reservoirs shows that, in the Caofeidian 14- e structure area in the southern sub- sag of the Shanan Sag, the braid river delta facies sandstones are developed and these sandstones are surrounded by the effective source rocks. These conditions are superior to the hydrocarbon migration and accumulation, demonstrating a great potential of the lithologic reservoir exploration potential in the Caofeidian 14- e structure area. The presence of thick oil layer has already been proved by drilling, which indicates that this area is most favorable for exploration of lithologic reservoirs in the Shanan Sag.
HE Wenyuan , BAI Xuefeng , ZHANG Jinyou , ZHAO Ying , LIU Zhao , ZHONG Jianhua , SUN Ningliang
2024, 70(3):1159-1191. DOI: 10.16509/j.georeview.2023.12.031
Abstract:Shale oil of Qingshankou Formation of Upper Cretaceous in Gulong Sag, Songliao Basin. Methods: Based on electron backscattering and secondary imaging, combined with energy spectrum analysis and thin section observation, it is found that a kind of micron pore and micron fissures formed by hydrocarbon generation and expulsion expansion in Qingshankou Formation shale in Gulong Sag. Results: The characteristics of hydrocarbon generation and expulsion high-pressure expansion micron pores are: ① generally only developed in ultra-high pressure shale oil reservoirs; ② Generally only developed in clay feldspar shale, pure clay rock is rare; ③ Most of them are nearly circular or semi-circular, with diameters ranging from 0. 5 microns to several microns, generally 1~2 microns, but up to 8 microns; ④ The wall of the hole is generally clay, and the clay on the upper edge is curved or eyebrow shaped, and the chlorite is obvious, so it is bright and eye-catching in the backscatter image; ⑤ There are many self-generated nanoscale grape-like or soybean residue clay in the hole. ⑥ high-pressure expansion micron holes for hydrocarbon generation and expulsion can be combined into four types: vertically connected to form vertical hydrocarbon expulsion chimneys; Vertically connected to form a inclined hydrocarbon exhaust chimney; The hydrocarbon exhaust pipes connected horizontally to the bedding form larger lamellar pores in the profile. Straight or slightly curved hydrocarbon exhaust chimney; 1~3 microns wide, up to 200 microns wide; High ten to twenty or thirty microns, up to 1500 microns; The top is mostly connected with the micron slit along the bedding, which is the final pressure relief and oil and gas drainage reservoir of the hydrocarbon exhaust chimney. The porosity of hydrocarbon-generating and expelling micron pores varies greatly, generally in the range of 5%~6%. The characteristics of high-pressure expansion micron fractures for hydrocarbon generation and expulsion are: ① generally only developed in ultra-high pressure shale oil reservoirs; ② Generally only developed in clay feldspar shale, pure clay rock is rare; ③ Mainly micron cracks based on foliation; ④ slightly curved tensile cracks, mostly zigzag, bypassing minerals; ⑤ Width 1-tens of microns, up to 150 micron; ⑥ Associated with pyrite, dolomite, apatite and other authigenic minerals; ⑦ It is mostly connected with hydrocarbon generation and expulsion micron pores and expulsion chimneys. In this paper, the pressure to form the hydrocarbon-generating and expandable micropores and microcracks is calculated, and the hydrocarbon-generating and expandable micropores are formed from 44.74 MPa at 1500 m to 74.81 MPa at 2500 m depth. At the same depth, the pressure of hydrocarbon expulsion is 3 MPa larger than that of hydrocarbon expulsion micropore formation. Conclusions: This is a new genetic type of micron pore and micron fracture, is a kind of effective micron pores andmicron fractures, is the most important one in Gulong shale oil reservoir. There are two main driving forces for the formation of hydrocarbon generation and expulsion expansion micron pores: one is the high-pressure expansion tension of hydrocarbon fluids; The second is the chemical dissolution power of hydrocarbon fluids. The pressure to form the micron pore and micron slit of hydrocarbon generation and expulsion is calculated. The expansion of micron pores with hydrocarbon generation and expulsion is connected with other pores to form a storage and transportation network, which greatly increases the storage capacity and permeability of the reservoir, and is the main contributor to the recoverable reserves, which is the basis and guarantee for the development of Gulong shale oil.
ZHANG Chaokun , GONG Mingyue , TIAN Wei , HE Yanxin , ZHU Dongya , WANG Lei
2024, 70(3):1192-1204. DOI: 10.16509/j.georeview.2023.12.001
Abstract:Good sealing conditions are key to the preservation of helium resources, which play a crucial role in evaluating the exploration potential of helium resources in a certain area. Currently, the research on the capping characteristics of the helium reservoir is still in its infancy. In this paper, the characteristics of capping and sealing of helium reservoir are studied.Methods: In this paper, the capping mechanism and the relationship between macroscopic and microscopic characteristics of the capping layer and the sealing effect of helium were investigated by summarizing the capping characteristics of helium reservoirs all over the world. After that, the capping and sealing characteristics of the helium reservoir in Tarim Basin are analyzed.Results: The sealing mechanism of helium reservoir mainly includes three sealing mechanisms: physical property sealing, pressure sealing and concentration sealing. The sealing effect of cap rock on helium reservoir is affected by a series of microscopic characteristics (porosity, permeability, breakthrough pressure, median radius) and macroscopic characteristics (lithology, thickness, diagenesis, continuity, tectonics). The sealing ability of cap rock on helium gas is also different due to the different carrier gas types of helium reservoir. The sealing conditions of Hetianhe Block and Yakela Block are more favorable to the Gucheng Block, conventional methods for evaluating capping conditions of hydrocarbon reservoirs are not fully applicable to the assessment of capping conditions of helium resources.Conclusions: According to the relationship between the cap rock characteristics and the sealing efficiency of the helium reservoir summarized in this paper, the cap conditions of the helium reservoir can be preliminarily evaluated. The research on the method of accurately analyzing the cap conditions of the helium reservoir is still in the exploration stage and will be the focus of future work.
XU Xiaolei , BAI Chenyang , SU Pibo , MA Qian , ZHANG Yu , LIANG Jinqiang
2024, 70(3):1205-1220. DOI: 10.16509/j.georeview.2023.11.061
Abstract:As a new type of clean energy to replace conventional fossil energy, natural gas hydrate research has been increasingly emphasized by the academic community. In the past 40 years, western countries have carried out a large number of investigations and studies on natural gas hydrates, and systematic research has been carried out on the mineralization conditions, distribution law, formation mechanism, exploration technology, economic evaluation and environmental effects of natural gas hydrates. In order to investigate the effect of mineral type on gas hydrate formation, the following studies are carried out in this paper. Methods: Whole rock and clay mineral XRD test analysis, specific surface area analysis, and comprehensive analysis of irreducible water capacity were carried out using the samples from site W07 and their hydrate saturation data in Shenhu Sea, northern South China Sea. Results: The results show that 110~127 meters below sea floor is the hydrate reservoir section and 127~156 meters below sea floor is the non- hydrate reservoir section. The XRD analysis shows that the layers with high quantity of quartz and feldspar and low quantity of I/S mixed- layer mineral have lower specific surface area and irreducible water capacity, which indicates that they have relatively good pore permeability conditions, providing good spatial conditions for hydrate transport and storage, and therefore forming hydrate reservoir sections; while in the layers with high quantity of I/S mixed- layer mineral, the specific surface area is larger, the irreducible water capacity is stronger, and its adsorption and irreducible capacity of methane gas and fluid are stronger, and its adsorption and irreducible capacity for hydrate are stronger irreducible capacity, which plays a potential sealing role for hydrate formation and becomes non- reservoir section. Reservoir and non- reservoir section vertical stacking sequence is conducive to the formation of high- quality hydrate reservoirs. Conclusions: The present study summarizes the relationship between mineral components and high- quality hydrate reservoirs, and reveals the potential genesis links between the two, with a view to enriching the basic theory of hydrate enrichment and reservoir formation, and supporting the future commercial development of natural gas hydrates in the northern part of the South China Sea.
DUAN Zhuang , GAO Jilei , MA Ming , FENG Qiwei , LI Chunjia , LI Siyuan , LI Yong , LIN Lujun , FU Yangang , GAO Jianweng , HAO Zejiang , LI Yan
2024, 70(3):1220-1224. DOI: 10.16509/j.georeview.2023.11.025
Abstract:钴是高温合金、电池材料、防腐材料、磁性材料等重要原料,广泛应用于航空航天、电子电器、机械制造、汽车、化工农业、陶瓷等领域,在国民经济和社会发展中具有特殊的意义。特别是从移动电子设备,到新能源汽车的动力电池,再到电网储能,钴作为锂电池正极材料——钴酸锂的重要组成,都是不可或缺。因此,钴被世界上众多国家列为21世纪重要的关键战略资源(Gulley et al., 2018)。现今我国是世界上最大的钴资源进口国(95%依靠进口)和消费国(US Geological Survey, 2018),而且钴资源紧缺,保障程度低(蒋少涌等,2019;许德如等,2019)。因此,在复杂的国际政治和经济形势下,摸清我国钴资源的家底,增强我国钴矿资源供应保障程度,对我国国民经济发展和国家安全保障具有重要的战略意义。我国钴矿床类型多样,包括岩浆铜镍硫化物型、红土风化型、沉积砂岩型、热液型(如沉积喷流型、矽卡岩型、斑岩型、IOCG型等)(王辉等,2019;许德如等,2019;卢宜冠等,2020)。然而,与世界上钴矿资源相比,我国钴矿规模小、品位低,大部分钴矿为伴生矿,钴多作为副产品回收利用,主要伴生铜、镍金属产出,其次伴生铜铁矿床。其中,矽卡岩型矿床是我国伴生钴矿的一种重要类型,富钴矽卡岩矿床主要发育在东昆仑地区、长江中下游和冈底斯地区。目前,关键金属元素在自然界的矿物和岩石中赋存状态研究已广泛开展,但在矿山尾矿中的赋存状态和可回收利用性研究则相对薄弱。基于山东省新一轮找矿突破战略行动及鲁西地区矽卡岩型铁矿尾矿综合利用程度低等背景,为有效发挥尾矿二次资源的作用,摸清尾矿中伴生的矿产资源的可利用性,本次选取山东省莱芜垂阳铁矿床开展了尾矿中伴生矿产资源的综合利用评价工作,大致查明垂阳铁矿尾矿中可利用伴生资源类型、赋存状态及推荐选矿工艺。通过铁矿尾矿中伴生矿产资源综合利用评价工作,对提高山东矽卡岩型铁矿床中矿产资源综合利用水平,提升战略性矿产资源安全保障能力,助力山东省新一轮找矿突破战略行动具有重要意义。
2024, 70(3):1225-1228. DOI: 10.16509/j.georeview.2023.11.075
Abstract:北碚,地处重庆主城西北部,背靠缙云山,嘉陵江环城而过,拥有宜人的自然风光和厚重的人文底蕴,历史上翁文灏、黄汲清、李春昱、侯光炯等科学巨匠都曾在此耕耘,特别是1937年~1945年日本侵略中国期间,一大批东部地区科研学术机构和科学工作者西迁于此,得以延续中国科学文化的国脉和精华,北碚成为了抗日战争时期大后方闪耀的科技文化中心,当时,在中国近代历史上建立最早、机构最完备、科研水平最高的中央地质调查所(The National Geological Survey of China)就是其中之一。本文追溯了中央地质调查所在抗战时期西迁北碚,在学术研究、科学救亡方面作出的巨大贡献,以供世人追忆和缅怀。
2024, 70(3):2024030000-2024030000.
Abstract:
Fu Yangang , Cai Yongwen , Ma Shengming , Tang Shixin , Lin Jiansui , Hu Shuqi , Su Lei , Gao Jianweng , Gong Jingjing , Yang Jianzhou , Wang Zhenliang , Duan Zhuang , Hao Zejiang , Lin Lujun , Zhao Keqiang , Li Yong
2024, 70(3):2024030002-2024030002. DOI: 10.16509/j.georeview.2024.05.015
Abstract:Soil is the product of rock weathering, and the interplay between rocks and soil is a fundamental aspect of Earth System Science with direct relevance to human activities. To explore the material composition and evolutionary dynamics of the rock—soil system, it is imperative to select in- situ weathered areas for comprehensive soil vertical profile sampling. Drawing upon data from the Hainan Island Regional Ecological Geological Background Survey Project, this article presents a scientifically grounded approach for identifying eluvium profiles. In addition, the paper summarizes the vertical distribution law of chemical elements in the rock—soil system of the basalt formation in northern Hainan. By utilizing the geochemical data from the vertical profiles of Hainan basalt, the following conclusions are drawn: The SiO2 content in the vertical profiles shows a characteristic of high values in the A layer and rock, and low values in the B and C layers, which is opposite to the trend of Al2O3 content. There is an inverse relationship between these two representative components. Other components follow the same trend based on their affinity, while certain trace elements that are significantly influenced by surface activities, such as organic matter and I, do not conform to this pattern.
GAO Zhujun , WANG Dong , LI Zhongdong , YANG Jinshan , HU Jian , PENG Xiangrong
2024, 70(3):2024030003-2024030003. DOI: 10.16509/j.georeview.2024.05.042
Abstract:Daocheng County, located in the southern part of the Yidun island arc belt, has rich types of geological relics, huge vertical elevation difference, three- dimensional climate and unique landforms, which have created many magnificent natural landscapes. It is known as “the last pure land on the blue Mercury”. However, it has never comprehensively and systematically sorted out the geological relics resources in Daocheng area. We have classified and summarized the geological relics in Daocheng, clarified their distribution characteristics and scientific connotation, and put forward corresponding protection and utilization suggestions, laying a scientific foundation for the development of local tourism economy.Methods: Through the detailed investigation of geological relics and the data combing of the previous investigation work, according to the “Geological Relics Investigation Specification” (DZ/T0303- 2017), the geological relics in the study area are classified and summarized, and their types and distribution characteristics are clarified. Excavate and enhance its scientific connotation, and from the perspective of tourism geology, put forward suggestions for protection and utilization, and provide ideas for the construction of the Aden Geopark in Daocheng and the protection and utilization of geological relics.Results: There are abundant types of geological relics in Daocheng area, which are divided into 3 groups, 8 types and 17 subtypes, including basic geology, geomorphological landscape and geological disasters, with a total of 194 sites. Among them, there are 171 geomorphological landscapes, accounting for 88.14% of the total number of geological relics, accounting for the absolute dominant position; there are 69 water landforms in the class, accounting for 35.57% of the total. Among the subtypes, only the ancient glacial relics subtypes≥50, the largest number. These 194 geological relics are intrinsically linked in genesis and space, and can be summarized as 15 important geological relics concentration areas.Conclusions: ① The geological relics of Daocheng are controlled by the influence of strata and structures, characterized by various geomorphological landscapes, showing “linear” and “agglomeration” distribution; ② due to the influence of the “north—south high middle low” geomorphological pattern, the distribution of geological relics is obviously controlled by altitude, and each has its own characteristics. All kinds of canyon forms and glacier landforms are distributed. Based on the types, characteristics and distribution of the geological relics landscape in Daocheng area, some suggestions for protection and utilization are put forward: ① Strengthen the integration of geological culture; ② the rational planning of geological tourism products; ③ innovate the way of popular science propaganda ; ④ pay attention to all kinds of “Geology+” brand creation.
JIN Bingfu , WU Bo , ZHANG Yunji , YU Jian , HAN Xujiao , HASI Eerdun , SU Zhizhu , KONG Deyong , LI Xiubin
2024, 70(3):2024030004-2024030004. DOI: 10.16509/j.georeview.2024.05.012
Abstract:A significant quantity of lithic fragments is observed in the sediment of the Kumtagh Desert, which predominantly comprising coarse- grained materials such as gravel and coarse sand, as a temporary intermediate product of weathering in sedimentary parent rock, the lithic fragments, serve as the most reliable and direct indicator for determining the nature and provenance of the Desert sediments. Methods: we quantitatively analyzed the rock and mineral composition of various landforms in different parts of the Kumtagh Desert, including graben valley terrace, marginal platform, feathery dune in the northern region, as well as diluvial platform, dry riverbed, marginal dune and interdune in the southern region. For the first time in the Kumtagh Desert research history, we employed lithology microscopy identification methods using a large number of multiple samples to obtain results. Results: The findings reveal that there is a diverse range of fine gravel and coarse sand debris types present in the Kumtagh Desert. These include three major classes (igneous rock, metamorphic rock and sedimentary rock), 14 third- grade classes and 121 fifth- grade rocks. The predominant lithologies consist mainly of middle—acid effusive rocks and regional metamorphic rocks such as rhyolite, felsite, andesite, trachyte, quartzite and quartzitic rock. Whether it is a rock or a mineral is closely related to the size of the sand particles, about >90% of the gravel and 50% to 90% of the coarse sand are rock debris. The maximum lithology species is found at the grain size of 1.0mm, and the finer the sand grain, the higher the content of detrite minerals. This situation results in regional differences in lithology distribution in different regions and geomorphologic locations of the Desert due to the different grain size of the sand. Various major lithic fragments may exhibit different colour, with the dark particles are mainly composed of medium—acid extrusional rocks, while the light particles are mainly composed of quartzy rocks and felsic minerals, some of which have both dark and light colors. Notably, the lithology found in the Desert closely resembles that observed in the Altyn Tagh. The Kumtagh Desert contains not only typical dynamic metamorphic rocks found in the Altyn Tagh but also various rock types belonging to the unique ophiolite hybrid series present within Hongliugou—Lapeiquan member of the Altyn Tagh. This observation strongly suggests that coarse debris composition of the Kumtagh Desert originates from weathering processes acting upon parent rocks located within the Altyn Tagh; meanwhile differences in weathering patterns among parent rocks and the detrital output at different historical stages of mountain uplift contribute to variations between Desert lithology composition and that found within mountain parent rocks. Microcrystalline and cryptocrystalline resistant rock types are predominant components among Desert sand debris due to their resistance against weathering processes; in contrast, granitic rocks and intermediate—high grade metamorphic rocks characterized with coarse- grained (megacrystalline) structures are more prone to decomposition into individual minerals, serving as primary material sources for fine sands found within Deserts.The distribution pattern of coarse crystalline rocks and clastic single minerals exhibits a greater prevalence in the southern region compared to the northern region, while resistant rock debris is more abundant in the north and less so in the south within the Kumtagh Desert. Conclusions:The lithology of the gravel and coarse sand in different areas of the Kumtagh Desert is comparable to that of the predominant lithology in the Altun Tagh area, suggesting that the Desert debris primarily originates from alluvial and diluvium sediments in the Altun Tagh area. The southern edge of the Desert exhibits a higher proportion of coarse crystalline lithic fragments and single mineral content, while the northern part contains a greater amount of fine crystalline debris resistant to weathering. It can be inferred that initially, water power transports the Desert material along the terrain from south to north, which is then further modified by wind power near its source and in situ.
LI Wenqi , LIU Huichuan , LIU Xiaoping , YU Zhiqi , Wang Yiren , WANG Yingying
2024, 70(3):2024030005-2024030005. DOI: 10.16509/j.georeview.2024.05.022
Abstract:The North China Craton stands as one of the most ancient cratons worldwide, with its continental crust undergoing multiple episodes of crustal growth events. Considerable research has been conducted on the growth of the continental crust in the North China Craton. However, previous discussions on the crustal growth of basement beneath the Yanliao Rift Basin, obscured by extensive deposits of thick sedimentary cover, have been relatively scarce.Methods: Taking the sedimentary rocks of the Mesoproterozoic Changcheng System above the basement of the Yanliao Rift Basin as example, this study systematically analyzes the detrital zircon age spectra and Lu—Hf isotope data from the Changcheng System strata within the Yanliao Rift Basin. The investigation aims to elucidate scientific inquiries concerning the sedimentary age of the Changcheng Formation, the provenance of detrital zircons and crustal growth events.Results: The isotopic ages constrain the sedimentary age of the Changcheng System in the Yanliao Rift Basin as ca. 1680 Ma, which represent the timing of initiation of the Yanliao Rift. The detrital zircon age spectrum from the Changcheng System in the Yanliao Rift Basin primarily exhibits two stages: 2.7~2.5 Ga and 2.2~1.9 Ga. The Hf isotope εHf(t) values manifest in a high positive range of 0.1 to 34.6. By comparing the detrital zircon U- Pb dating, Lu—Hf isotope εHf(t), and TDM2 model age data of the Changcheng System with the crystalline basement of the North China Craton, it is inferred that the sediment source of the Changcheng System in the Yanliao Rift Basin is the underlying basement of the Yanliao Rift Basin.Conclusions: ① The detrital zircon age spectrum of the Changcheng System in the Yanliao Rift Basin defines two major age populations two main stages: 2.7~2.5 Ga and 2.2~1.9 Ga. The Hf isotope εHf(t) values exhibit a high positive range between 0.1 and 34.6. ② Combining zircon U- Pb dating, zircon Lu—Hf isotope εHf(t) and TDM2 model age, it is suggested that there are three distinct episodes of crustal growth in the Yanliao Rift Basin of the North China Craton during the Neoarchean to Paleoproterozoic Eras, occurring at 2.7~2.5 Ga, 2.2~1.9 Ga, and 1.7~1.6 Ga.
WANG Xiaorui , YANG Ruidong , CHEN Rong
2024, 70(3):2024030006-2024030006. DOI: 10.16509/j.georeview.2024.05.055
Abstract:Scandium (Sc) and its compounds have been widely used in scientific, technology and military fields due to the excellent properties, thus Sc has been listed as strategic mineral resource in China. The Sc was found enriched in the weathering crust of the Emeishan basalt in Dali, Yunnan Province, specifically, the average content of Sc is 43.7 μg/g, which is equivalent to scandium oxide (Sc2O3) of 67.01 μg/g. The content of Sc2O3 in the reddish-brown clay layer within the weathering crust is relatively higher at 81.31 μg/g, which reaches the industrial grade of Sc deposit. Sc derived from the parent rock Emeishan basalt is enriched in the weathering products probably due to its low migration ability in the weathering process. Since the Emeishan basalt distributes widely in the Yunnan, Guizhou and Sichuan area, SW China, the Sc-rich basalt weathering crust may become a potential Sc source.
YAN Houbei , WANG Zhiqiang , SUN Keke , YUAN Feng , TAO Nai , ZHANG Jun
2024, 70(3):2024030007-2024030007. DOI: 10.16509/j.georeview.2024.05.035
Abstract:In order to study the possible formation mechanism of MME in the Jingde pluton. Mineral chemical analyses of granodiorite and biotite in the MME were conducted to qualify the magma crystallization conditions and establish the diagenetic link between the MME and host granodiorite.Methods: Combined with field work and microscope observation, using EPMA and LA- ICP- MS analysis of biotite and plagioclase to constrain the origin of MME.Results and conclusion:(1) In the Jingde pluton granodiorite and MME formed at analogous temperatures (824~864 ℃, 802~828 ℃), pressures (0.354~0.787 GPa, 0.279~0.353 GPa) and oxygen fugacity (-13.4~-12.7, -12.8~-11.2), respectively.(2)The compositions of biotite and plagioclase in the Jingde pluton MME are comparable to that of the host granodiorite, indicating that MME is not of crust—mantle mixing origin, but a cognate magmatic evolutionary relationships.(3)The enriched mantle was partially melted induced by the subduction of the Paleo- Pacific plate and formed basaltic magma. The underplated basaltic magma evolved to intermediate melt by differentiation. Early low-evolving magma is the magma chamber cooled first by upward introsions due to lower viscosity, followed by a large-scale upward intrusion of highly evolved granodiorite magma. The cooled semi- plasticized intermediate rocks in the magma channel were dragged and wrapped to form MMEs in the granodiorite.
ZHOU Tangbo , LI Jun , JIANG Weibing , ZHONG Fujun , LI Haidong , GUO Xinwen , XU You
2024, 70(3):2024030008-2024030008. DOI: 10.16509/j.georeview.2024.05.025
Abstract:The Huangshaqiao uranium deposit is located in the southern part of the Zhuguangshan composite pluton, on the west side of the Chengkou ore concentration area. In this paper,zircon LA- ICP- MS U- Pb dating,Hf isotope and geochemical composition measurements have been carried out for the granite of the Huangshaqiao uranium deposit. The results show that the ages of the medium—coarse grained porphyritic Biotite granite and the medium—fine grained porphyritic Biotite granite are 152.8±1.1 Ma and 154.1±1.4 Ma,respectively. The results of element analysis show that the two types of Biotite granites are rich in silicon,alkali,high K2O/Na2O ratio and low CaO/Na2O ratio,both of which have relatively consistent REE and trace distribution curves;They are relatively enriched in large ion lithophile elements Rb and high field strength elements Th,U,and Hf,with significant depletion of elements such as Ba,Nb,and Ti. Both have obvious light and heavy rare earth fractionation characteristics,with rare earth partitioning curves showing a right- dipping pattern and distinct negative Eu anomalies. Both types of Biotite granite have lower εHf(t)values (-15.24~-8.96and-13.60~-9.65),and their Paleoproterozoic model ages(2171~1778Ma and2063~1821Ma).Both types of Biotite granites belong to strongly aluminous S- type granites,which are mainly partially melted from clay rich argillaceous Sedimentary rock. Both are products of Yanshanian magmatic activity,formed by low degree partial melting of the crustal source area dominated by the Paleoproterozoic era under the extensional tectonic background caused by the subduction of the Pacific Plate.
2024, 70(3):2024030009-2024030009. DOI: 10.16509/j.georeview.2024.05.021
Abstract:To clarify the law of vertical distribution of oil and gas in the middle and upper part of oil and gas-bearing basins under the combination of fault-cap configurations.Methods: based on the research on the characteristics of the closed combination of fault-cap configurations and the vertical distribution of oil and gas transportation and gathering under them, a set of methods for the depiction of the vertical distribution of oil and gas transportation and gathering in the middle and upper part of oil and gas-bearing basins under the combination of fault-cap configurations are established through the superposition of the source rock-rooted fault transmission and gas transmission parts, and the source rock-rooted fault and the upper, middle, and lower part of regional mudstone caprock configurations that are closed and closed parts. It was used to delineate the longitudinal distribution of oil and gas transportation and gathering in the Gangdong fault of the Qikou sag in the Bohai Bay Basin and the regional mudstone caprock configuration combination of the middle part of the 1st member of the Shahejie Formation (Es1z), the 2nd member of Dongying Formation (Ed2) and the Minghuazhen Formation (Nm) in the lower sub-member of the 1st member of the Shahejie Formation (Es1x). The 3rd member of the Dongying Formation (Ed3) and the Neoproterozoic Guantao Formation (Ng). Results: The results show that the longitudinal distribution of oil and gas transport in the Es1z, Ed2and Nm under the combination of Gangdong fault and the Es1z, Ed2 and Nm is mainly in the east and west, and the longitudinal distribution of oil and gas transport in the Es1z, Ed2 and Nm under the combination of Gangdong fault and the Es1z, Ed2 and Nm are mainly in the east and west. The vertical distribution of oil and gas transport in Ed3 and Ng under the combination of the Gangdong fault and the regional mudstone caprock configurations of Es1z, Ed2 and Nm is mainly located in the middle of them. The vertical distribution of oil and gas transportation is relatively developed in Es1x under the combination of the Gangdong fault and the configuration of Es1z, Ed2, and Nm, which is favorable for oil and gas transportation and the formation of reservoirs. The vertical distribution of hydrocarbon transport in Ed3 and Ng under the configuration combination of the Gangdong fault with Es1z, Ed2 and Nm is relatively undeveloped, which is not conducive to the formation of reservoirs by hydrocarbon transport. This coincides with the current oil and gas distribution in Es1x, Ed3 and Ng at the Gangdong fault.Conclusions: This method is feasible to delineate the longitudinal distribution of oil and gas transport under the fault-cap configuration combination.
GUO Lifei , PAN Baolin , WANG Junping , CHENG Xinlin , YANG Yong , ZHOU Rui , LIU Xiuying , CAI Zhuoyun
2024, 70(3):2024030010-2024030010. DOI: 10.16509/j.georeview.2024.05.041
Abstract:A series of Cenozoic basins are formed in the Hexi Corridor in the northeast. Clarifying the sedimentary history of these Cenozoic basins is of great significance for understanding the tectonic growth process and dynamic mechanism and the sedimentary evolution history of the Wuwei Basin since the Late Middle Pleistocene in thenortheast margin of Tibetan plateau.Methods: This paper takes investigated the WV3 borehole core in the middle and lower reaches of Shiyang River in the Wuwei Basin, in the eastern part of Hexi Corridor. The OSL dating andgrain size testing were employed for reconstructing the chronological framework and the sedimentary characteristics of sediments above 17 m in WV3 borehole since late Middle Pleistocene.Results and Conclusions: The results of 19 two-step PIR200IR290s and 2 multi-step MET-pIRIR dating were obtained, and the OSL dating framework of sediments above 17 m in WV3 borehole since late Middle Pleistocene was established. The results show that the two-step pIR200IR290 and multi-step MET-pIRIR test ages are consistent within the margin of error. During the period of 220~128 ka, the deposition rate was the lowest, 0.35 mm/ka, and the hydrodynamic conditions were strong. During the 128~108 ka (MIS 5d, MIS 5e) period, the sedimentation rate was 1.94 mm/ka, and the sediment grain size changed from coarse to fine, indicating that the hydrodynamic conditions changed from strong to weak. From the last glacial maximum to the early Holocene (19-9 ka), the deposition rate was 2.78 mm/ka, and the sediment grain size was relatively fine, indicating that the hydrodynamic conditions were weak at this time and the deposition rate was maximum. The neotectonic movement is relatively active in this area, and there are thrusting activities during the last interglacial to the last glacial maximum. This study is of great significance for revealing the sedimentary characteristics of Shiyang River Basin in eastern Qilian Mountains since late Middle Pleistocene.
HUO Hongliang , LIU Chenglin , LI Wenda , ZANG Qibiao , LI Guoxiong , LU Zhendong , SU Jiajia , YANG Yizhuo
2024, 70(3):2024030011-2024030011. DOI: 10.16509/j.georeview.2024.05.041
Abstract:This paper aims to study the characteristics and distribution of tight sandstone reservoirs deposited by gravity flow in deep water. Specifically, the study focuses on the 7th Triassic Yanchang Formation (Chang 7) member in the Heshui area of Ordos Basin. Methods:The analysis is conducted through the core description, cast thin slice, and scanning electron microscope observation. By combining physical property data and analytical laboratory data, the study analyzes the petrology, pore types, and diagenetic characteristics of the Chang 7 reservoir in the study area. Additionally, the formation mechanism of a high-quality reservoir is discussed based on sedimentary and diagenetic characteristics. Results: The reservoir of Chang 7 in the Heshui area mainly comprises feldspar lithology. The pore types are mainly solution and residual intergranular pores, which belong to the ultra-low porosity and ultra-low permeability reservoirs. The main diagenetic processes are compaction, cementation, and dissolution. The quality of gravity flow tight sandstone reservoirs is controlled by sedimentary facies, compaction resistance, illite mineral content, and feldspar and other minerals dissolution. Reservoirs deposited in restricted channels generally have the best reservoir quality under relatively weak compaction, cementation, and strong dissolution. Sandstones in different sedimentary environments have differences in particle size, sorting, and sedimentary thickness, which can control reservoir quality by influencing diagenetic type and intensity. Conclusions: There are differences in particle size, sorting and thickness of reservoirs formed in different sedimentary environments, which lead to differential diagenesis and affect reservoir quality. Based on this, a quality evolution model of tight sandstone reservoirs under gravity flow sedimentary background is established. The research results can provide a reference for predicting and evaluating the same type of reservoir.
LIU Chuangxin , GAO Hongyan , LIU Binbin , LI Wenjun , HUANG Zhilong , QU Tong , YANG Yizhuo , XIA Yu , SHAN Lijun
2024, 70(3):2024030012-2024030012. DOI: 10.16509/j.georeview.2024.05.031
Abstract:Huagang Formation sandstone reservoir is an important exploration target in Xihu Depression, and the study of reservoir heterogeneity is crucial. Based on the analysis of reservoir diagenesis and diagenetic evolution, this paper clarifies the difference between the north and south of the central inversion zone, and further analyzes the causes of the difference.Methods: In this study, one type of thin sections were made, including casting thin sections and the production process was all in accordance with the Chinese oil and gas industry standard (Y/T5162- 2014). All the thin sections could be used to analyze the mineral composition and pore geometry. The casting thin sections were stained with blue epoxy resin to identify the pore type and size distribution, and a Leica DM4500P/DFC450C high-precision microscope was used for the observation. SEM is a common electronic imaging technique, which is mainly used to observe the pore structure of rocks at micro/nano scale. This study adopted two methods to observe SEM, one was to use Quanta-200F field emission SEM (with X-ray energy spectrometer) with a minimum resolution of 1. 2 nm to observe the pore type, mineral composition, diagenesis, and pore connectivity. The XRD experiment could be used to analyze the mineral composition. Before the experiment, samples need to be crushed in an agate container to a particle size of < 200 mesh. Take 100~200 g of the original sample, bake until dry, then weigh it, take an appropriate amount of sediment sample into a container, add water to diffuse, and use a 63~125 μm copper sieve for sorting. After screening out the particle size, it is weighed dry and its mass fraction is calculated; Take 1~2 grams of sorted samples, separate them with tribromomethane heavy liquid, dry and weigh them, and calculate the mass fraction of heavy minerals.Results:The northern region has stronger compaction and dissolution, and can be divided into three diagenetic zones, acid, acid-base transition and alkaline, with two stages of siliceous cementation and three stages of calcareous cementation. The southern area has two stages of calcareous cementation with shallow burial depth and low geothermal temperature, and can be divided into two diagenetic zones, acidic and alkaline. The analysis of heavy minerals and hydrocarbon generation intensity shows that the Huagang Formation reservoir in the northern region has the characteristics of low porosity and high permeability.Conclusions: Through thin section observation, scanning electron microscopy, reservoir physical properties, heavy mineral composition, clay mineral content, and other research and analysis, it is believed that the northern region has stronger compaction and dissolution effects. Vertically, it is divided into three diagenetic zones, acid, acid-base transition and alkaline with boundary of 3500 m and 4000 m. It undergoes two stages of siliceous cementation and three stages of calcareous cementation. The southern area, with shallow burial depth and low geothermal temperature, has only two stages of calc cementation, and is divided into two diagenetic zones, acidic and alkaline, with a boundary of 4000 m. Due to the contribution of more magma source rocks, the compressive strength of the Huagang Formation reservoir in the northern region is poor, and it is subjected to stronger compaction, and the stronger hydrocarbon generation strength of source rocks makes the reservoir suffer stronger dissolution. Therefore, the reservoir of Huagang Formation in the northern region has the characteristics of low porosity and high permeability.
PEI Xiaolong , TIAN Ye , YUAN Shisong , QIN Tian , LIU Hang , ZHU Xiaosong
2024, 70(3):2024030013-2024030013. DOI: 10.16509/j.georeview.2024.05.061
Abstract:The construction of ecological civilization in the new era has put forward higher requirements for scientific management of natural resources and modern governance of national land and space. Based on this, the Ministry of Natural Resources has issued the "Overall Plan for the Construction of a Natural Resources Survey and Monitoring System", proposing the concept of "ground substrate" for the first time, and has organized pilot investigations of ground substrate in typical areas. However, there is currently no unified understanding and standard for the three-level classification, survey objects, survey content, and technical system of ground substrate, which seriously restricts the research work of ground substrate investigation. Methods: This study deeply analyzes the scientific connotation of ground substrate, comprehensively considers the data support needs of land agricultural space, land ecological space, and land urban spatial planning, and establishes a layered classification model of ground substrate based on the spatial attribute characteristics of ground substrate. Based on the classification principles of scientificity, uniformity, operability, and applicability, a three-level classification scheme for ground substrate has been proposed, further exploring and clarifying the investigation objects and contents of ground substrate layered classification, and establishing a set of ground substrate investigation and monitoring technology system.Results: ① A spatial stratification model for ground substrate is constructed in the form of "soil layer-sedimentary layer-bedrock layer", which realised the articulation and correspondence between ground substrate layers and substrate types. ② A three-level classification scheme for ground substrate is proposed, which divided the surface substrates into 4 first-level classes, 14 second-level classes and 55 third-level classes. ③ The survey objects and contents of surface substrates are clarified, and the investigation should focus on the distribution of each surface substrate type, physical and chemical properties and geological landscape attributes. ④ A technical system for surface substrate investigation and monitoring has been established, which mainly includes data integration, field investigation, results analysis, simulation and prediction, and other key technical links.Conclusions: In this study, a systematic technical system for ground substrate investigation and monitoring is established through the study of the theoretical model, research object, investigation content, technical methods, and application of ground substrate, which can provide a theoretical basis and reference for further investigation and research of ground substrate.
XIANG Xibin , LI Haixia , LIU Huipeng
2024, 70(3):2024030014-2024030014. DOI: 10.16509/j.georeview.2024.05.001
Abstract:To verify the electromagnetic interference effects of multi-rotor UAV in semi-airborne transient electromagnetic exploration, and develop effective noise reduction methods to improve the quality of exploration signal data.Methods: The time-frequency noise analysis is carried out to detect the electromagnetic interference generated by multi-rotor UAV (taking DJI T20 as an example) under different working conditions.The influence of the distance between the noise source (UAV) and the receiving point on the noise level is studied.A recursive least square method based on moving window is proposed and applied.Results: It is found that the main frequency band of periodic electromagnetic interference generated by motor rotation of DJI T20 UAV is 550~900 Hz.When the distance between the receiving coil and the UAV is 10m, the above interference can be ignored.Noise reduction experiments prove that the proposed adaptive noise reduction method can suppress the interference effectively and restore the original characteristics of the signal.Conclusions: It is proved by experiments that the electromagnetic interference of multi-rotor UAV in semi-airborne transient electromagnetic exploration can be observed, especially at close range.By applying recursive least square method based on moving window, the electromagnetic interference generated by UAV can be effectively reduced and the original characteristics of the disturbed signal can be restored.The application of the noise reduction technology to actual geological exploration data processing can significantly improve the data quality, and is conducive to further geological interpretation and mineral resource evaluation.
YAN Xinyue , GU Bingluo , SUN Zhiguang , ZHANG Yongjie , ZHANG Xinyi
2024, 70(3):2024030015-2024030015. DOI: 10.16509/j.georeview.2024.05.011
Abstract:With the continuous deepening of oil and gas exploration in China, complex high-steep structural areas have increasingly become the focus of oil and gas exploration. The existing imaging methods cannot meet the imaging requirements of high-steep structures around wells. According to the principle of seismic interferometry, different wave field components of VSP data are separated, and different wave field components are mathematically calculated to generate interference gathers. The seismic interferometry can make the virtual observation system closer to the target area, improve the imaging resolution of the high-steep interface, and achieve high-precision imaging for the high-steep structure around the well.Methods: For the high-steep structure in the well, the seismic interferometry method is based on the source-receiver reciprocity theorem. The VSP data at different detection points are processed by correlation / convolution, and the virtual source data is reconstructed to obtain a virtual SWP seismic record with one detection point as the virtual source and the other detection point.Results:The perturbation theory is used to analyze the role of different wave field components in the interference process. Through the window function filter and seismic interference imaging method, the salt dome model is imaged and compared with the reverse-time migration imaging effect, and the high-precision imaging of the salt dome model is obtained.Conclusions:Using seismic interferometry, VSP wave field can be transformed into SWP wave field, which makes the observation system closer to the underground structure and realizes high-precision imaging of underground high-steep structures.
SONG Jiye , QIN Mingkuan , CAI Yuqi , WANG Jianfei , ZHANG Yuhui , ZHANG Xiao , LIN Shuangxing
2024, 70(3):2024030016-2024030016.
Abstract:At present, the importance of energy security (especially uranium resources) has become more prominent. Real-time tracking of the exploration and development status and investment environment of major overseas uranium resources and uranium-producing countries is of great significance to support Chinese enterprises to go out for overseas uranium resource exploration and development. Based on the latest data, the uranium resources characteristics in Namibia have been systematically analyzed. The results show that Namibia is rich in uranium resources, and its main genetic types of uranium resources are intrusive and surfical deposits. From 2010 to 2021, Namibia's natural uranium production has overall increased with an increase of 76.6%. Exploration progress has been made in resource additions, prospecting space expansion, new potential type discoveries and some mine are expected to begin commercial production in the future. Namibia is generally a country with a better investment environment for uranium resources exploration and development. We think it’s a good pattern for our national enterprises to carry out uranium resources exploration and development in Namibia, that the existing mines controlled by Chinese enterprises can be taken as the center, and radiate uranium projects in the surrounding areas while paying attention to distance, production center sharing, etc., and adopt three levels and three modes for Namibian uranium resources exploration and development.
PAN Feifei , CHEN Danli , BAI Heling , LIU Guannan , HUANG Haitao , LIU Jing , ZHAO Yuanyi
2024, 70(3):2024030017-2024030017. DOI: 10.16509/j.georeview.2024.05.075
Abstract:A great amount of heavy metals were discharged into the surface water in west Henan molybdenum ore concentrated area during mining activities, resulting in obviously negative influence on the quality of the surface water and human health. However, the sources of heavy metals in surface water and their pollution level have been unclear.Methods: Some surface water samples were collected from five rivers in the Luanchuan ore concentration area during the wet and dry seasons in 2019. Heavy metals (Mo、Cd、Hg、As、Cr、Cu、Pb、Zn) in the surface water were determined. Pollution level and human health risk induced by drinking surface water were also assessed by single factor assessment, comprehensive pollution index and health risk assessment model. Results: The results indicated that Mo/Zn/Cd and Mo/Hg/Cd were the primary pollutions in the surface water during wet season and dry season, respectively. In the surface water, Mo was mainly originated from Mo min; Pb and Zn were mainly derived from Pb/Zn mine and Mo mine; Cd was mainly originated from Au mine and Pb/Zn mine; Hg was mainly derived from Au mining activities. All rivers in the studied area were suffered by heavy pollution. Moreover, the quality of surface water in dry season was worse than that in wet season. For the different rivers, the quality of surface water was followed by Yi River>Shibaogou River>Taowanbeigou River>Yu River>Beigou River in wet season and Yi River>Shibaogou River>Yu River >Taowanbeigou River>Beigou River in dry season. The results were attributed to the types of mines and intensity of mining activities along the rivers. The levels of total individual annual health risk were all lower than the acceptable risk levels of US EPA. However, the levels of total individual annual health risk for children in wet and dry season and adults in dry season were higher than the acceptable risk levels of ICRP.Conclusions: The investigation and assessment of the heavy metal pollution in the surface water in Luanchuan ore concentrated area can contribute to pollution control and environmental management of heavy metal pollution in the surface water.
WU Haowen , SU Zhongtang , PEI Wenchao , WEI Liubin , REN Jing , ZHANG Chenggong , FU Shiyi
2024, 70(3):2024030018-2024030018. DOI: 10.16509/j.georeview.2024.05.002
Abstract:The Ordovician Majiagou Formation in the Ordos Basin has become the most popular carbonate formation in the Ordos Basin, because of its potential for oil and gas exploration, but its age attribution is still controversial. The Upper Member of the Ordovician Majiagou Formation (referred to as the “Ma- 5” Member) is characterized by the presence of two layers of tuffs, which are commonly used as regional marker beds for stratigraphic correlation. Investigation of the zircon ages of these tuffs can help establish the chronostratigraphic framework of the Majiagou Formation and provide insights into its depositional period and tectonic settings. Methods: We performed zircon SHRIMP U- Pb dating and zircon microzonation in situ Hf isotope characterization of the Ma- 5 Member tuffs in the Well S148 and the Well T56 in the Ordos Basin.Results: The zircon SHRIMP U- Pb dating data of tuff shows that the 206Pb/238U age of tuff samples from the Well T56 ranges from 442.3 Ma to 474.3 Ma, with a weighted average age of 460.9±2.9 Ma, and that of tuff samples from the Well S148 ranges from 442.0 to 471.6 Ma, with a weighted average age of 458.4±2.4 Ma. The measured n(176Hf)/n(177Hf) ratios of in- situ zircon Hf isotopes range from 0.282687 to 0.280820, and εHf(t) values vary from 6.67 to 11.32, with two- stage model ages ranging from 720 to 1024 Ma.Conclusions: Based on the zircon dating results of the tuffs of the Majiagou Formation, the deposition of the Majiagou Formation is constrained to the Middle Ordovician Darriwilian to Upper Ordovician Sandbian stages. Comparison of the zircon U- Pb ages and Hf isotope characteristics of the tuffs surrounding the basin suggests that the volcanic tuffs of the Majiagou Formation may have originated from the North Qinling Mountains and/or North Qilian Orogenic Belts in the southwestern part of the basin. Furthermore, it is inferred that prior to the emplacement of the tuffs, the North Qinling and/or North Qilian Ocean initiated a northward subduction and entered a stage of ocean—land transition, indicating the transformation of the western and southern margins of the basin into an active continental margin during the late Middle Ordovician.
Editor in chief:YANG Wencai
Inauguration:
International standard number:ISSN 0371-5736
Unified domestic issue:CN 11-1952/p
Domestic postal code:2-382