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    Overview of the Application and Prospect of Common Chemical Weathering Indices
    LI Xulong, ZHANG Xia, LIN Chunming, HUANG Shuya, LI Xin
    Geological Journal of China Universities    2022, 28 (1): 51-63.   DOI: 10.16108/j.issn1006-7493.2020118
    Abstract3118)      PDF (1109KB)(3997)       Save
    Common chemical weathering indices such as the Weathering Index of Parker (WIP), the Chemical Index of Alteration (CIA), the Index of Compositional Variability (ICV), CIX index and αAlE are often used to evaluate the chemical weathering intensity of source areas. But the factors which controlling the above chemical weathering indices should be considered, otherwise the results of the weathering evaluation will be distorted. This paper argues that the geological survey of source area should be known when chemical weathering indices are used to study the chemical weathering process. The selection of fine sediments or suspended matter can weaken the influence of grain size on chemical weathering indices. The impurities in the sediments are removed by acid treatment. Then, the Sc/Th-CIA diagram was used to reflect the material source information, Th/SC-Zr/Sc diagram was used to further distinguish the control effect of sedimentary differentiation and sedimentary recirculation, and then the samples with ICV value less than 1 were selected to eliminate the interference of recirculation. The A-CN-K diagram or the formula proposed by Panahi (2000) were used to correct the potassium metasomatism, and the strength of chemical weathering of source rocks was evaluated by CIA eventually. To ensure that the calculation of chemical weathering indices can accurately reflect the weathering situation of the source area, SPSS software can be used to analyze the proportion of some factors which affecting the CIA to construct characteristic weathering index of the study area.
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    Advances in the Study of Biogeochemical Cycles of Phosphorus
    ZHOU Qiang, JIANG Yunbin, HAO Jihua, JI Junfeng, LI Wei
    Geological Journal of China Universities    2021, 27 (2): 183-199.   DOI: 10.16108/j.issn1006-7493.2020002
    Abstract1693)      PDF (2398KB)(1700)       Save
    Phosphorus is an essential element for life and an important limiting factor for food production. The biogeochemical cycles of phosphorus not only regulate marine primary production, but also has an impact on the global climate system; it also determines the formation and distribution of phosphate resources and affects the continuity of life on earth. The current theory of “earth system science” integrates the subsystems of atmosphere, hydrosphere, lithosphere (crust and upper mantle) and biosphere, providing a broader view for studying the global phosphorus cycles. Based on the existing research and combined with the theory of “earth system science”, the following important understandings of the biogeochemical cycles of phosphorus has been obtained: The evolution of phosphorus in geological history determines the current cycle pattern of phosphorus on a global scale (terrestrial ecosystems and marine ecosystems); Human industrial and agricultural activities, as an important geological agent, has changed the biogeochemical cycles of phosphorus, resulted in resource crisis of phosphate depletion and environmental problem of eutrophication of water bodies; The key to solve the resource crisis problem of phosphorus shortage and environmental pollution problem of phosphorus surplus lies in regulating the biogeochemical cycle process that cause these problems. 
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    Advances on Surficial Geochemistry Database and Related Research
    XU Yijiang, LI Chenglong, TAN Haolin, SHENG Xuefen
    Geological Journal of China Universities    2021, 27 (1): 58-72.   DOI: 10.16108/j.issn1006-7493.2021003
    Abstract632)      PDF (2242KB)(1100)       Save
    Surficial Geochemistry is an interdisciplinary study of the earth’s surface system, which is closely related to climate, environment, and human being. With the advent of the era of big data, surficial geochemistry is facing new opportunities and challenges. In order to provide reference for the construction of the big data platform of the Deep-Time Digital Earth Project (DDE), this paper conducts a preliminary investigation on the existing surficial geochemical data and databases. The results show that the surficial geochemical data have the characteristics of diversity and inter-disciplinal. Most data are lacking of standards and in an unstructured state; larger databases such as GEOTRACES and PANGAEA have relatively accepted data standards and data management experience; SISAL database has achieved key results in the task of data structuring; which are all worthy of further study. The works of surficial geochemistry big data science construction should be guided by research goals and needs, and by setting up corresponding scientific working groups as joined forces to promote the digitalization of surficial geochemistry discipline.
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    Genetic Types and Accumulation of Crude Oil in the Central Inversion Zone in the Liaoxi Depression, Bohai Sea
    TIAN Derui, NIU Chengmin, WANG Deying, GUO Tao, PAN Wenjing, GUO Longlong
    Geological Journal of China Universities    2021, 27 (4): 444-458.   DOI: 10.16108/j.issn1006-7493.2020093
    Abstract409)      PDF (1211KB)(1037)       Save
    The central inversion zone of the Liaoxi Depression is the enrichment area of high quality light crude oil in the Liaodong Bay exploration area. However, the genetic types, source and accumulation of crude oil have not been systematically studied. Based on the analysis and comparison of the biomarkers, three sets of effective source rocks of the Shahejie Formation were distinguished. The first, third and fourth members of the Shahejie Formation, are obviously different in the source of organic matter and sedimentary environment. It is confirmed that plankton is the main component of organic matter in the three sets of source rocks. The first member of the Shahejie Formation (E2s1) has the highest plankton content and the least terrestrial organic matter input. The content of dinoflagellate in the fourth member of the Shahejie Formation (E2s4) was significantly higher than that in the first and third members of the Shahejie Formation (E2s1, E2s3). Both E2s3 and E2s4 source rocks were deposited in the freshwater and weakly alkaline reducing environment, and the E2s1 source rock was deposited in the brackish to saline alkaline strongly reducing environment. The crude oil found in the central inversion zone can be divided into three source-related types through hierarchical cluster analysis(HCA). The oil-source correlation results show that the type Ⅰ crude oil is the mixed oil originated from the E2s3 and E2s1 source rocks, which is mainly distributed in the middle block and the middle area of the east block on the central inversion zone. The type Ⅱ crude oil is originated from the E2s4 source rocks, which is distributed in the southern area of the east block on the central inversion zone. The type Ⅲ crude oil is the mixed oil originated from the E2s3 and E2s4 source rocks, which is mainly distributed in the west block and the northern area of the east block on the central inversion zone. On this basis,

    the main controlling factors of hydrocarbon accumulation in the central inversion zone of the Liaoxi sag were analyzed. Oil and gas
    reservoirs on the central inversion zone are controlled by multiple factors, including the distribution of effective source rocks and the math of fault and sand bodies.

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    Construction of Nb-Ta Deposit Knowledge Graph and Its Application
    RAN Yizao, DONG Shaochun, WANG Rucheng, HU Huan, FANG Siyuan, CHANG Fengnian, KONG Jia
    Geological Journal of China Universities    2023, 29 (3): 359-371.   DOI: 10.16108/j.issn1006-7493.2021107
    Abstract145)      PDF (4845KB)(319)       Save
    As an important resource for emerging industries, critical metals have gradually gain attention both domestically and overseas in recent years. However there are still some bottlenecks existing in the critical metal research due to its low abundance, difficulty to trace, identify and separate. As an important infrastructure of big data and artificial intelligence, knowledge graph provides new insights to tackle these issues. Most of the research achievements related to critical metal deposits are published in academic journals, which are written in natural language and is difficult to be understood and directly used by machines. In this paper, the ontology layer of Nb-Ta deposit knowledge graph was constructed and data extracted from literatures consists of the fact layer of the Nb-Ta deposit knowledge graph. Based on the Nb-Ta deposit knowledge graph, the features and relationships among the metallogenic periods, types of Nb-Ta deposits and the co-occurrence of niobium and tantalum related minerals were analyzed. It will help to further reveal the spatio-temporal distribution and evolution characteristics of China Nb-Ta deposits. 
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    Enzyme-induced Calcium Carbonate Precipitation (EICP) and Its Application in Geotechnical Engineering
    CAO Guanghui, LIU Shiyu, YU Jin, CAI Yanyan, HU Zhou, MAO Kunhai
    Geological Journal of China Universities    2021, 27 (6): 754-768.   DOI: 10.16108/j.issn1006-7493.2020200
    Abstract1721)      PDF (4975KB)(1287)       Save
    The technique of improving soil by enzyme-induced calcium carbonate precipitation is called EICP, which has attracted more and more attention over the past decade due to its wide application. The article describes the mechanism of EICP and summarizes the extraction methods of plant urease and bacterial urease. In addition, the influence of factors such as urease, calcium source, urea, skimmed milk powder, temperature and pH on the cementing effects of EICP is explored. Furthermore, methods for testing the strength, calcium carbonate content, microstructure and composition of EICP reinforced samples are summarized, and the application of EICP in geotechnical engineering is evaluated. The purpose of this article is to summarize the current status of EICP research and potential problems that need to be overcome in future research.
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    Predevonian Tectonic Evolution of South China: from Cathaysian Block to Caledonian Period Folded Orogenic Belt
    SHU Liang-shu
    J4   
    Abstract2090)      PDF (501KB)(4169)       Save
    The interpretation of Predevonian tectonics of South China is controversial long time both on its age and distribution. Based on the middle-high grade metamorphic rocks, ductile slipping rheologic structures exposed in the the Zhejiang- Fujian-Jiangxi-Guangdong domain and high quality dating data published recently, the author believes that an ancient continental block existed certainly in South China, which is composed of Proterozoic schist, gneiss and migmatite with an oldest age of 2 Ga, their protolites are clastic rocks, volcanic rocks and plutons. This old land is temporarily called as Cathaysian Continental Block which is limited in the domain between Shaoxing-Jiangshan-Pingxiang fault and Zhenghe-Dapu fault, and its scope is less than that defined by Grabau. During 800-900 Ma, following the closure of paleo-South China ocean, Cathaysian block collided with Yangzi block and then became a part of Rodinia supercontinent. Not long time after converging, by affection of breakup of Rodinia supercontinent, proto-Cathaysian continental block was split into three sub-blocks, namely the southeastern Zhejiang-northwestern Fujian, the central-southern Jiangxi and the Yunkaidashan, and several rifts or sea channels occurred among them. From Early Sinian to Late Ordovician, these sea channels were expanded and were filled by 10000-20000 m thick clastic rocks (containing limestone) and turbidites. However coeval ophiolite and volcanic rocks are absent, implying extended fault did not reach to upper mantle. New geochronological results indicate that the ophiolite and volcanic rocks in the study areas, which were described as Early Paleozoic by previous researchers, yielded pre-Sinian ages, concentrating mainly between 800 Ma and 900 Ma. Thus, the previous Early Paleozoic tectonic framework needs to be re-constructed. In Silurian, a strong tectono-thermal event took place in South China, causing closure of Sinian-Early Paleozoic sea channels and folding-uplifting of mega-thick sediments. The South China Caledonian fold and orogenic belt was formed on the Proterozoic metamorphic basement. In the study area, folding deformation and ductile slipping rheology are very common, including thrust and strike-slip deformation, the peak period of deformation is 420-400 Ma. At the same time, a violent granitic magmatism was started, forming numerous strongly peraluminous S-type granites with A/CNK (molar Al2O3/[CaO + Na2O + K2O]) > 1.1, and I-type granitoids is rare. Peak period of granitic magmatism took place in the 430-400 Ma. Then, the whole South China Caledonian folded geological bodies were overlain unconformably by Late Devonian conglomerate and coarse sandstone, indicating termination of folding and orogeny. From Late Devonian, a united paleo-geographic and sedimentary environment occurred really in the study domain and its neighboring areas.
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    3D Digitization of Geological Outcrops and Specimens:Status and Prospects
    XU Qi, SHEN Hanxiao, DONG Shaochun, SHI Yukun, FAN Junxuan
    Geological Journal of China Universities    2023, 29 (3): 403-418.   DOI: 10.16108/j.issn1006-7493.2022092
    Abstract167)      PDF (3613KB)(370)       Save
    In the era of big data, the high techniques such as knowledge graph, artificial intelligence and virtual simulation rapidly developed, and as a result the research methods of geosciences are evolving with the times. Compared to the traditional two-dimensional images and texts, three-dimensional digital models can provide more diverse data, and therefore hold enormous potential for both the scientific research and technology fields. The digitization of geological outcrops and specimens are two typical cases of 3D modeling technology in geoscience. This paper investigated the construction of digital outcrop and 3D specimen digitization, introduced the common digitization technologies, data sharing and development services, and the current representative digital geological outcrop and 3D specimen database. The investigation results were summarized and analyzed. Moreover, some problems that exist at present were summarized, and the future development was prospected in terms of data construction standard specification, construction content and function expansion.
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    An Overview of Characteristics and Prospecting of Gold Ore Deposits in China
    WANG Bin,LI Jingchao,WANG Chengxi,ZHENG Xiao,SUN Kefeng
    Acta Metallurgica Sinica    2020, 26 (2): 121-.   DOI: 10.16108/j.issn1006-7493.2019033
    Abstract474)      PDF (2571KB)(836)       Save
    Based on the geodynamic settings of gold metallogenesis and the basic geological features of gold ore deposits, China’s gold deposits can be classified into 11 categories. Among these categories, the structurally-fractured altered-rock type, inner and outer contacting belts type of plutonic intrusives, the Carlin or quasi-Carlin type, hydrothermal type within low-grade metamorphic clastic rocks, and continental volcanic rock types are the types of interest in prospecting. As far as metallogenic ages concerned, those that occurred in Mesozoic and Cenozoic are the major types. According to their geotectonic units, geological evolution, metallogenic geological conditions, spatial-temporal distribution, gold deposit types, regional metallogenic factors, and volumes of mineral resources, totally 42 gold ore concentration areas, which are spatially distributed in clusters, have been preliminarily identified on the basis of China’s III-graded classification scheme of metallogenic zones (belts). According to gold prospecting borehole quantities per unit area, China’s gold ore concentration areas can be categorized into 3 levels, i.e., highly, moderately, and lowly developed. The highly developed ones are mainly distributed in Central and Eastern China. Except the placer gold deposits, about 88.12% boreholes for primary gold (rock gold or associated gold) deposits are less than 500 m with deep in China, suggesting that the quantities and depths of gold exploration drillings in China are less and shallower than in other countries. As for the gold resources exploration potentials, we propose that (1) in Central and Eastern China, the deep parts and the peripheries of the existing gold mines are key locations to be focused on; (2) for Western China, the gold ore concentration areas, which are located especially in Xinjiang Uygur Autonomous Region, Qinghai Province, and Tibet Autonomous Region, are the future key regions with immense potentials for unexplored gold resources.
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    Construction Method and Comparison of Global Paleogeographic Reconstruction Models and Associated Knowledge Discovery
    HOU Zhangshuai, FAN Junxuan, ZHANG Linna, SHEN Shuzhong
    Geological Journal of China Universities    2020, 26 (1): 86-.   DOI: 10.16108/j.issn1006-7493.2019105
    Abstract611)      PDF (2615KB)(1108)       Save
    Paleogeographic models contain reconstructions on position and motion of the tectonic plates and their surface features, and
    serve as the framework for geological history reconstruction in the Deep-time Digital Earth (DDE) Big Science Program. Based on different data and methods, a lot of global paleogeographic models have been proposed in the past decades. Recently, it has become more common to use data from various fields such as paleomagnetism, paleontology, sedimentology, geophysics, geochemistry, and geodynamics to establish a digital, detail-adjustable, and self-evolving model. The current paper reviews the existing methods of global paleogeographic reconstruction models, and conducts a comprehensive comparison of the six main reconstruction models (PaleoMap, PLATES, UNIL, GOLONKA, GMAP, and EarthByte), as a reference for domestic research. We also introduced the applications and knowledge discoveries of reconstructed paleogeographic models in the field of paleoclimate, plate tectonics, and basin evolution. Under the framework of DDE program, a unified four-dimensional paleogeographic model will be reconstructed with efforts from paleogeographic scientists all over the world.
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    High Precision Analytical Method for Stable Strontium Isotopes
    CHEN Xuqi, ZENG Zhen, YU Huimin, HUANG Fang
    Geological Journal of China Universities    2021, 27 (3): 264-274.   DOI: 10.16108/j.issn1006-7493.2021031
    Abstract995)      PDF (922KB)(722)       Save
    Because of the development of high-precision stable Sr isotope analytical method, stable Sr isotopes have been paid more attention in recent years. Great progress has been made in studies on supergene geochemistry, paleoenvironment, archaeology, endogenesis, and meteorites. This paper summarizes the key techniques of δ88/86Sr analytical methods. Ion exchange method with Eichrom Sr Specific Resin has been widely used to purify Sr. But this specific resin is expensive and may result in contamination during the chromatographic processes. Thus it could be replaced by cation-exchange resin. MC-ICP-MS and TIMS are the instruments for isotope measurement. Normally, MC-ICP-MS has higher measurement efficiency but slightly lower precision than TIMS. Standard-Sample-Bracketing method, Zr-Empirical-External-Normalization method, and double spike method are used to correct the instrumental mass bias. The Double Spike method may have relatively high measurement precision, but there are only a few studies using this method on MC-ICP-MS. Furthermore, there is no detailed comparison of δ88/86Sr of international standard materials. Therefore, optimizing the analysis process, improving the measurement precision, and more determination of δ88/86Sr of standard materials are necessary for the future studies of stable Sr isotopes.

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    Late Mesozoic Bansin and Range Framework and the Related Tectono-Magmatism of Southeast China
    DONG Changchun, SHU Limin, SHU Liangshu
    Geological Journal of China Universities    2023, 29 (2): 223-239.   DOI: 10.16108/j.issn1006-7493.2021053
    Abstract1326)      PDF (2209KB)(291)       Save
    The Southeast China Block was located in the back margin of the Late Mesozoic Japan-Taiwan volcanic arc. The middle Jurassic-late Cretaceous extensional basins and volcanic-intrusive rock series are widely developed in the Southeast China region as a response of ancient Pacific Plate subduction toward the eastern Asia Continent leading the back-arc expansion. The types of basin include the middle Jurassic rifts, the late Jurassic-early Cretaceous volcanoclastic and lava faulted-depression basins and the late Cretaceous-Paleogene redbed faulted-depression basins. The igneous rock series consists mainly of granitoids, bimodal magmatic rocks, A-type granites, metamorphic core complexes and doming-shape plutons, which were formed in the early Cretaceous with a peak value of 140-110 Ma). The basins coexist together with coeval plutons and constituted the Early Cretaceous Southeast China Basin and Range tectonics. This study summarized the principal geological features of the Late Mesozoic Southeast China basin and range geomorphology and analyzed the petrological and geological structural marks and the constraint factors forming the Southeast China bansin and range framework. Finally we discussed the Late Mesozoic geodynamic process of the Southeast China region.
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    Geology and Geomorphology of Tarim Basin and Its Evolution in the Cenozoic
    LI Jianghai,WUTongwen,LEI Yuting
    Acta Metallurgica Sinica   
    Characteristics and Formation Mechanism of Zeolite in the Northwestern Margin of Junggar Basin: A Case Study of the Permian Urho Formation in Manan Area
    LIAN Lixia, WANG Jian, YANG Zhao, MA Cong, LUO Zhengjiang, YANG Shengchao, ZHANG Wenjie, HU Wenxuan
    Geological Journal of China Universities    2021, 27 (1): 102-110.   DOI: 10.16108/j.issn1006-7493.2019107
    Abstract416)      PDF (4202KB)(520)       Save
    Zeolite is a type of special cement developed in the Permian Wuerhe Formation in the Manan area of the northwestern Junggar Basin. The mineralogical characteristics, spatial distribution, genetic mechanism and reservoir formation mechanism of zeolite cement in the study area were investigated, by using combined methods including core observation, thin section identification, SEM analysis and rock composition statistics. Results show that laumontite and heulandite are the two main types of zeolites developed in the Wuerhe Formation of the study area. Specifically, the heulandite has two phases, i.e., iron-rich in the early phase and iron-poor in the late phase. They can also be distinguished by the color of the cements under microscope: the early phase in red and the late phase without color. The spatial distribution of the zeolites in the study area does not have an obvious pattern. In contrast, vertically the content of laumontite and heulandite has a gradual decrease trend from the Wuerhe Formation to the Baikouquan Formation. The formation of zeolite is mainly controlled by the components of tuff gravel in the parent rock. The intermediate-acid rock gravel is unfavorable for the formation of laumontite, and there is no obvious relationship between the other volcanic gravels and the formation of all kinds of zeolites in the study area. The widespread secondary dissolved pores of laumontite are the main reservoir space in the study area for hydrocarbon accumulation. The precipitation and dissolution of zeolites are a complex diagenetic effect that can be summarized into a two-stage diagenesis processes. In the early stage, the normal diagenesis formed diverse kinds of zeolite cements under an alkaline environment that rich in metal ions. In the late stage, deep fluid upwellings that contain acidic hydrocarbon-bearing fluids dissolved and altered the reservoirs. The deep fluid alteration is the key stage of reservoir formation in the Manan and its adjacent areas of the northwestern Junggar Bsin, which is important for the formation of commercial oil accumulation.

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    The Petrogenesis of Baishuizhai Granitic Pluton and Its Significance to Uranium Mineralization in the Xiazhuang Area, Guangdong Province
    LI Kun, CHEN Weifeng, GAO Shuang, SHEN Weizhou, HUANG Guolong, LIU Wenquan, FU Shuncheng, LING Hongfei
    Geological Journal of China Universities    2023, 29 (4): 497-513.   DOI: 10.16108/j.issn1006-7493.2021117
    Abstract316)      PDF (2375KB)(379)       Save
    The Baishuizhai pluton is one of the main ore-bearing wall rocks of the Zutongjian uranium deposit in the northwestern part of the Xiazhuang granite-related uranium ore filed, yet its petrogenetic mechanisms and its relationship with uranium mineralization are still unclear. Thus, in this study, we present zircon SHRIMP U-Pb ages, whole-rocks and mineral geochemical data for the Baishuizhai granite. Field and petrographic investigations show that the Baishuizhai granitic pluton was emplaced into the Xiazhuang granitic batholith, mainly composed of fine-grained two-mica granite and muscovite granite, and the zircon SHRIMP U-Pb dating reveals that both granites were formed during the Indochina period with ages of 229.4 Ma and 231.8 Ma, respectively. They show typical peraluminous S-type granitic geochemical characteristics that are high SiO 2 contents, total alkalis contents and ACNK values ( ≥ 1.1), low FeOt+MgO+TiO 2 contents and P 2O 5 contents, enriched in Rb, Th and U, depleted in Ba, Sr, P and Ti, and enriched in aluminum-rich minerals. Compared with the Xiazhuang granite, both types of granites in the Baishuizhai pluton show enriched in inherited zircon, higher SiO 2 contents and Rb/Sr ratios, but lower FeOt+MgO+TiO 2 contents, P 2O 5 contents, Zr/Hf ratios, and Fe 2+/(Fe 2++Mg) ratios of biotites, indicating that they were derived from low partial melting of reducing material-rich feldspathic meta-pelites, and are not formed by the differentiation evolution of the parent magma of the mafic meta-pelites-derived Xiazhuang granite. Furthermore, compared with the two-mica granite, the muscovite granite display significant tetrad REE patterns, lower REE, Zr/Hf ratios and Eu/Eu* values, indicating that an interaction of F-rich fluids with the magma occurred in the formation of the muscovite granite. Both types of granites in the Baishuizhai granitic pluton are enriched in uranium and can be important uranium-bearing granites in the region. Relative to the 2-mica granite in the Baishuizhai pluton, the muscovite granite is more enriched in uranium and more favorable to be uranium source rocks for hydrothermal uranium mineralization.

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    Characteristics and Genesis of Mesozoic A-Type Granites and Associated Mineral Deposits in the Southern Hunan and Northern Guangxi Provinces along the Shi-Hang Belt, South China
    JIANG Shao-Yong, ZHAO Kui-Dong, JIANG Yao-Hui, DAI Bao-Zhang
    J4   
    Abstract2849)      PDF (2672KB)(2525)       Save
    The Shi-Hang belt is an important magmatic zone composed of granites with relative higher εNd(t) values and younger tDM model ages and trends NNE. The granites in Southern Hunan and Northern Guangxi include the Qianlishan, the Qitianling,the Xishan, the Jinjiling, the Huashan and the Guposhan granites. Recently a series of zircon SHRIMP U-Pb ages indicate that all these granites were emplaced in a narrow time interval of 151~163 Ma. However, ages of granites decrease from the southwest to the northeast. These granites have similar geochemical characters. All of them are enriched in alkalies and potassium, and have high contents of LILE and HFSE. In geochemical discriminating plots, these granites fall in A-type granite field. Thus, the Southern Hunan-Northern Guangxi granite belt belongs to an A-type granite belt. These granites are further classified to A2 type.These granites have relatively lower (87Sr/86Sr)i values, higher εNd(t) values and younger t DM model ages. From the southwest to the northeast, εNd(t) values gradually decrease. Abundant mafic microgranular enclaves were found in most granites. Petrogeology and geochemistry, especially Hf isotopes of zircon from the MMEs and host rocks indicated that these granites formed by crust-mantle magma mixing processes. The mantle-derived magma end-member came from depleted mantle, and might be directly related with the asthenospheric mantle. The A-type granite belt might form at back-arc or intra-arc extension environment triggered by subduction of palaeo-Pacific plate. The strong mantle-crust interaction caused by upwelling and underplating of the asthenospheric mantle across the trans-crustal faults is the major mechanism for generating the A-type granites in the belt. The extension and thinning of the continental crust began from the southwest to the northeast, and the intensity of extension decreased from the southwest to the northeast. The Shi-Hang South Belt is an important W-Sn mineralization belt. All these granites belong to Sn-rich granite. Mechanism of tin concentration in these granites is different with common tin granites, in which tin is concentrated by fractional crystallization. Tin mineralization models are abundant in the belt. Different with traditional tin mineralization model,tin mineralization in the Furong tin deposit was related with chloritization of granites by later meteoric water hydrothermal system.Studies on these granites and related tin mineralization may enrich mineralization theories of A-type granites.
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    Comparison and Subdivision of Loess Strata in the Chinese Loess Plateau
    WANG Yang,SUN Hongyan,TIAN Mingzhong
    J4    2015, 21 (2): 346-.   DOI: 10.16108/j.issn1006-7493.
    Abstract1280)      PDF (953KB)(1862)       Save
    Based on the comprehensive analyses of the previous research on the loess stratigraphic classification in the Chinese Loess Plateau, and results from the three type loess/paleosol profiles, i.e., Luochuan, Baoji, and Xifeng, this article conducted detailed comparison and further subdivision of the loess strata in the Chinese Loess Plateau by using soil stratigraghy, sedimentology, magnetostratigraghy, paletontology, chronology, and geochemistry. This article adjusted the boundary of the Early Pleistocene and the Middle Pleistocene to the top of L9, which corresponds to the start time of the B/M polarity boundary, divided the Lishi Loess into three parts according to the difference in lithology and climate cycle periods, and added S8/L9 as a new boundary. As a result, S1-L5 are in the upper Lishi Loess, S5-S8 are in the middle Lishi Loess, and L9-L15 are in the lower Lishi Loess. A new problem arises that the ages of some key horizons such as the S0, L1, S1, S5, L9, L15 and L33 are different among these profiles.
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    W-Sn-Nb-Ta-Bearing Granites in the Nanling Range and Their Relationship to Metallogengesis
    CHEN Jun, LU Jian-Jun, CHEN Wei-Feng, WANG Ru-Cheng, MA Dong-Sheng,ZHU Jin-chu, ZHANG Wen-lan and JI Jun-Feng
    J4   
    Abstract2968)      PDF (3275KB)(3709)       Save
    The large-scale mineralizations of W, Sn, Nb and Ta related to granites took place in the Late Jurassic period in Nanling Range, South China. According to the petrological and geochemical features of ore-bearing granites and their relationship to mineralizations, they can be grouped into the following three major types: W-bearing granites, Sn-W-bearing granites and Ta-Nb-bearing granites. The W-bearing granites show low TiO2 and Ba+Sr contents and LREE/HREE ratios,intensive Eu depletion, high Rb and Y abundances and Rb/Sr ratios, and oversaturation in Al. They commonly underwent intensive differentiation and evolution. The Sn-W-bearing granites are characterized by enrichment of TiO2, total REE, HFSEs,Ba+Sr and Rb, higher CaO/(K2O+Na2O) and LREE/HREE ratios, metaluminous-weakly peraluminous feature and lower Rb/Sr ratios, and weaker differentiation and evolation. The Ta-Nb-bearing granites have very low TiO2, Ba+Sr, total REE and HFSEs contents and CaO/(K2O+Na2O) ratios, higher Al2O3/TiO2 and Rb/Sr ratios, higher Rb and Nb contents, and ACNK values. They are highly evolved. Good discrimination can be obtained between these three types of W-Sn-Nb-Ta-bearing granites on plots employing Nb-Y-Ce, (Ba+Sr)-Rb-(Zr+Nb+Ce+Y), LREE/HREE-Rb/Sr and LREE/HREE-(Zr+Nb+Ce+Y) diagrams. These three types of ore-bearing granites have obviously different evolutional trends. Metallogenesis is intimately related to the evolution of the ore-bearing granites. Mineralizations of Sn, W or W-Sn and Nb-Ta or Sn-W-Nb-Ta are closely related to biotite granites, twomica granites or muscovite granites and albite granites respectively. The important deposit types of W, Sn, Nb and Ta and their major features in the Nanling Range are summarized in the paper. The chloritized granite type tin deposit is proposed. This paper indicates that an attention to searching for both the chloritzed granite type tin deposits and greisen-quartz vein type W-Sn deposits in W-Sn-bearing granites in the Nanling Range should be especially paid.
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    Cited: Baidu(96)
    Cathaysia Block:A Young Continent Comprising Ancient Materials
    YU Jin-Hai,WEI Zhen-Yang,WANG Li-Juan,SHU Liang-shu,SUN Tao
    J4   
    Abstract2096)      PDF (224KB)(2822)       Save
    Analyses of detailed dating results of zircons from metamorphic rocks in three areas of the Cathaysia block, where Precambrian rocks are exposed, indicate that the Cathaysia block may be subdivided into the Wuyishan and Nanling-Yunkai terrains. The Wuyishan terrain is composed of Paleoproterozoic basement metamorphic rocks and Neoproterozoic (730-820 Ma) meta- sediments, which is an oldest terrain in Cathaysia block. There may be Neoarchaean basement in the depth. Neoproterozoic sediments are from the old Wuyishan mirco-terrain itself. The Nanling and Yunkai regions have similar Precambrian crustal components, which consist of Neoproterozoic sediments and minor interbedded volcanic rocks. These sediments comprise very ancient Mesoarchaean and Neoarchaean components, even Paleoarchaean ones. The Grenvillian and Mesoproterozoic materials are most abundant in these sediments. However, these major components have no exposed counterpart rocks found in the Cathaysia block, implying that their provenance are from other continents previously linking with the Cathaysia block. This source continent is likely the Eastern India and East Antarctica. The Nanling-Yunkai area is originally a rifted sedimentary basin forming during the breakup of Rodinia supercontinent. Caledonian orogeny made the sediments in the basin compress, fold and uplift, forming a new young continent with old Wuyishan micro-continent
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    Status and Advances of Research on Caprock Sealing Properties of CO 2 Geological Storage
    CHEN Bowen, WANG Rui, LI Qi, ZHOU Yinbang, TAN Yongsheng, DAI Quanqi, ZHANG Yao
    Geological Journal of China Universities    2023, 29 (1): 85-99.   DOI: 10.16108/j.issn1006-7493.2023010
    Abstract1472)      PDF (6425KB)(551)       Save
    CO 2 Geological storage is one of the key technologies to address global climate changes and reduce greenhouse gas emissions. Large-scale CO 2 injection into the formation is prone to inducing CO 2 leakage problem. In particular, the leakage problem of CO 2 through caprock includes capillary leakage, hydraulic fracture and leakage along pre-existing faults crossing caprock. Therefore, evaluation of caprock seal is crucial for prediction of long-term safety and stability of CO 2 geological storage. This paper provides an overview of the current status of research on sealing mechanisms, influencing factors, and damage modes affecting caprock seal of CO 2 geological storage. It is concluded that caprock seal mechanisms include capillary seal, hydraulic seal, and overpressure seal. The main influencing factors of caprock seal characteristics include caprock lithology, mudrock-sand ratio, caprock mechanical properties, and sequestration pressure. Then, the damage modes of caprock seal during CO 2 injection are illustrated, and some insight into the shortcoming of caprock seal is provided.
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    Current Status of Paleontological Databases and Data-driven Research in Paleontology
    DENG Yiying, FAN Junxuan,WANG Yue,SHI Yukun,YANG Jiao,LU Zhengbo
    Acta Metallurgica Sinica    2020, 26 (4): 361-383.   DOI: 10.16108/j.issn1006-7493.2020018
    Abstract533)      PDF (7547KB)(728)       Save
    Fossils are invaluable information resources for understanding the deep-time Earth history. Over hundreds of years, a huge amount of paleontological data recording those information has been published. With the rapid development of computer, database and internet technologies during the past 30-40 years, those data have been gathered into various paleontological databases under different goals. The databases all have distinguished system structure, data organization method and service objects. In the present study we reviewed the development of major paleontological databases around the world, including their history, architecture, data characteristics and data volume. Their data organization methods, key online functions, data sharing mechanisms as well as the quality control technique of taxonomic data have also been compared and evaluated. Moreover, several cutting-edge data-driven paleontological research have been introduced. Based on the experience of their data application routine, a concept of establishing a harmonized paleontological big data platform containing data compilation, standardization, sharing, analysis and application, was proposed. It can serve as an example in the Deep-time Digital Earth (DDE) Big Science Program for the construction of multi-disciplinary geosciences big data platform.
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    Study on Heating Characteristics and Prediction Model of Igneous Rock under Microwave Irradiation
    ZHAO Qinhua, ZHAO Xiaobao, ZHAO Jianxin, LIU Hanwen, ZHENG Yanlong, LI Jianchun, HE Lei, HE Julong, YU Jiawang
    Geological Journal of China Universities    2021, 27 (1): 94-101.   DOI: 10.16108/j.issn1006-7493.2020003
    Abstract389)      PDF (1607KB)(429)       Save
    Microwave-assisted rock breaking can effectively reduce cutting tool wear and improve breaking efficiency, which has a broad prospect of engineering development. 10 kinds of igneous rocks were heated under microwave irradiation. The results illustrated that the heating rate depends on mineral species and content as well as the Fe content. The heating rate is higher when the rock contains more sensitive minerals and Fe. Generally, basic rock has the highest heating rate, followed by intermediate rock, acid rock the lowest. This phenomenon is related with the law of mineral and element composition in igneous rocks. Heating prediction model of rock was proposed based on experimental study. Except for mineral species and content, ratio and structure correction coefficients related to the temperature increment were also taken into consideration. In the heating prediction model, the ratio correction coefficient of sensitive mineral is bigger than 1, decreasing with the rise of its content, and eventually tending to 1. The ratio correction coefficient of non-sensitive mineral is smaller than 1, increasing with the rise of its content, and eventually tending to 1. The heating rate of block is twice to three times that of powder. The structure correction coefficient of basic rock is bigger than that of intermediate rock and acid rock.
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    Chloritization Sequences in Mudstone during Diagenesis and Its Geological Significance
    FU Yu, DING Qingfeng*, WU Changzhi
    Acta Metallurgica Sinica   
    Bio-geoengineering Technology and the Applications
    TANG Chaosheng, PAN Xiaohua, LYU Chao, DONG Zhihao, LIU Bo, WANG Dianlong, LI Hao, CHENG Yaojia, SHI Bin
    Geological Journal of China Universities    2021, 27 (6): 625-654.   DOI: 10.16108/j.issn1006-7493.2021011
    Abstract780)      PDF (4447KB)(763)       Save
    Bio-geoengineering technology is defined as a technology that using various types of microbial biochemical process to improve the hydro-mechanical behavior of soil and rock, aiming for the prevention and mitigation of engineering geology problems. Previous studies indicate that bio-geoengineering technology is a hot research topic in recent years and has the advantages of low cost, environmental friendliness, low energy consumption and process controllable. It has been recognized as an important development direction of modern engineering geology. Based on research progress on this topic, this paper systematically summarizes the principles and application fields of three representative bio-geoengineering technologies that can be well controlled and efficiently used, including bio-mineralization, bio-film growth and bio-gas production. It focuses on the engineering properties (i.e. mechanical behavior, permeability, and erosion resistance) and the corresponding involved mechanisms of the rock and soil improved by bio-mineralization that have been studied the most and with the broadest application prospects. Moreover, the key factors (i.e. bacteria species, bacterial solution concentration, environmental temperature, pH value, cementation solution composition, soil nature and grouting technology) that affect the improvement effect of bio-mineralization are discussed in depth. In addition, the application status of bio-mineralization in foundation treatment, island and reef construction, wind and sand fixation, soil and water conservation, crack resistance and seepage prevention, cultural relics protection, geological disaster prevention and other fields are introduced in detail. The main challenges of the application of bio-mineralization are listed, and the future research directions on this topic are proposed.

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    DistributionSummaryofCenozoic Basalts in CentralandEasternChina
    CHEN Xiayu, CHEN Lihui*, CHEN Yang, ZENG Gang, LIU Jianqiang
    J4    2014, 20 (4): 507-.  
    Abstract1956)      PDF (4273KB)(3051)       Save

    Abstract:Distribution information of Cenozoic basalts were extracted by pixel from the geological map of central and Eastern China,
    and overlaid on the high-precision geomorphologic map, utilizing a digital-rimage processing program. Based on this method, we
    estimated the total and sub-regional area of Cenozoic basalts exposed in Central and Eastern China. The main observations include:(1)
    The total area of Cenozoic basalts in Central and Eastern China is 78 525 km2. (2) The area of Cenozoic basalts in Central China is
    35 487 km2, while that in Eastern China is 43 038 km2, with a ratio of 45∶55. (3) The area of Cenozoic basalts increases along with
    younger age, and the ratio of which from Paleogene, Neogene, to Quaternary is 0.36∶21.65∶77.99. (4) Cenozoic basalts of Central China
    are mainly distributed in the north. Three main regions include: Great Xing'an Range, Xilin Gol region and northern edge of North
    China, with an area of 7334 km2, 13 843 km2, and 14 310 km2, respectively. (5) In Eastern China, Cenozoic basalts are more widely
    distributed, from Heilongjiang province in the north to Hainan Island in the south, and they can be divided into three regions: Northeast
    China to the east Songliao basin (33 324 km2), Eastern China including Shandong, Zhejiang, Jiangsu and Fujian provinces (1 707 km2),
    and Leiqiong region including Hainan Island and Leizhou Peninsula (8 007 km2). (6) Taken Shandong province as the boundary,
    Cenozoic basalts in Central and Eastern China are mainly distributed in the north with an area of 69 191 km2, while that of the southern
    part is 9334 km2, and their ratio is 88∶12.

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    Cited: Baidu(11)
    Research Progress and Prospect of the Gangdese Magmatic Belt in Southern Tibet
    MENG Yuanku, YUAN Haoqi, WEI Youqing, ZHANG Shukai, LIU Jinqing
    Geological Journal of China Universities    2022, 28 (1): 1-31.   DOI: 10.16108/j.issn1006-7493.2020057
    Abstract627)      PDF (2414KB)(986)       Save
    The Gangdese magmatic belt is the product of the northward subduction of the Neo-Tethys oceanic lithosphere beneath the Lhasa terrane and subsequent India-Asia collision. The Gangdese magmatic arc belongs to the typical continental magmatic belt and is the target area for studying plate accretion, crustal growth and reworking and collisional orogeny. Numerous lines of evidence indicate that the Neo-Tethys oceanic lithosphere experienced four distinct stages of evolution: the early-stage subduction (>152 Ma), late-stage subduction (100 to 65 Ma), main-collisional (55 to 40 Ma), and post-collision extentional stages (23 Ma to present). Multiple studies were carried out in the Gangdese belt and much progress has been made during past decades. However, the formation and evolution of the Neo-Tethys Ocean and magma source of igneous rocks are still debated, especially the detailed petrogenetic dynamic processes. This paper reviews the evolution history and tectonic background, and then summarizes related

    scientific problems from thirteen aspects. It is shown that the Gangdese magmatic belt is a typical magmatism-tectonismmineralization-deformational metamorphism belt and experienced multi-stage evolution processes rather than a simple
    continental magmatic arc aggregated in the Lhasa terrane. The review shows that (1) the Gangdese magmatic belt is a natural
    laboratory for studying the evolution history of the Neo-Tethys, and provides better constraints on the styles of the subducting
    slab. (2) The different-stage granitoid stocks and batholiths might be formed by multiple additions and incremental assembly of
    magmas over a span of millions of years or even longer. Therefore, we should use a mush model to reconstruct petrogenesis and
    petrogenetic secnarios of granitoid rocks in detail. (3) The mantle nature of the Gangdese region shows complicated features that
    are characterized by geochemical heterogeneity along the arc strike direction. (4) The reversed isotopes exist in the Gangdese belt, probably indicating an ancient nucleus. (5) The Gangdese belt is tilting and has different crustal compositions that are characterized by lower crustal compositions in the eastern segment and middle-upper crustal compositions in the middle-western segment. Crustal tilting of the Gangdese region suggests a differential and imbalanced exhumation process. (6) At present, numerous studies are focused on igneous rocks with methods mainly including radioactive Sr-Nd-Hf isotopes, whereas non-traditional stable isotopes (Mg-O-Li-B-Mo) are rarely reported. In addition, research topics are mainly associated with petrogenesis and geochronology, but few studies focus on the magma emplacement and post-magmatic deformation and uplifting-denudation processes. (7) Research in structural geology of the area is few and usually tectonic evolution is inferred from magmatic evolution in the Gangdese belt, southern Tibet. Finally, we also provide future prospects based on the current research status of the Gangdese magmatic belt in southern Tibet.

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    A Review of the Establishment Methods of Training Image in Multiple-point Statistics Modeling
    WANG Mingchuan, SHANG Xiaofei, DUAN Taizhong
    Geological Journal of China Universities    2022, 28 (1): 96-103.   DOI: 10.16108/j.issn1006-7493.2020049
    Abstract676)      PDF (1268KB)(778)       Save
    Multiple-point statistics (MPS) modeling has been the research hotspot of reservoir modeling technology in recent years, and its practicability is restricted by training image. The quality of training image determines the accuracy and reliability of MPS modeling, and is a key factor for the successful application of MPS modeling. This study addresses the characteristics and significance of training image, and systematically introduces the establishment methods of training image creation from the definition, usage and instance, etc., including hand drawn, object-based simulation, 3D seismic information extraction or transformation, prototype- ased model, process-based simulation and 2D image method. Then, our study comprehensively compares the data sources, advantages and disadvantages of various training image creation methods, and discusses the problems caused by MPS modeling relying on training images. Combined with reviewing prior works and MPS modeling practice, the research direction of training image and its establishment methods in the future is pointed out, which provides reference for MPS modeling researchers and users, and provides some thoughts for improving MPS modeling methods.
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    Petrogenesis and Geologic Implication of the Late Paleoproterozoic A-type Xiaohe Pluton along the Southern Margin of the North China Craton
    WANG Meixuan, WANG Zhiyi, ZHAO Jingxin, QI Zeqiu, HE Jun, CHEN Fukun
    Geological Journal of China Universities    2023, 29 (6): 809-830.   DOI: 10.16108/j.issn1006-7493.2022053
    Abstract97)      PDF (3050KB)(141)       Save
    Paleoproterozoic granitoids in the southern margin of the North China Craton are important carriers for studying the crustal evolution in Precambrian. In this study, we report zircon U-Pb ages and whole-rock geochemical compositions of the Xiaohe pluton exposed along the southern margin of the North China Craton in order to discuss its petrogenesis and significance for Precambrian crustal evolution. The Xiaohe pluton is composed of biotite-bearing monzogranite, geochemically, which can be divided into two categories according to its rare earth element characteristics. Type I shows the right dip distribution mode of light rare earth elements enrichment and heavy rare earth elements depletion, which has the characteristics of medium differentiation. Type II has a distribution pattern of rare earth elements with low total rare earth elements, insignificant fractionation of light and heavy rare earth elements, and depletion of middle rare earth elements, which has the characteristics of high differentiation. The zircon U-Pb dating on these two types of granite yielded ~1.80 Ga ages for the emplacement time of the magmas, indicating both of them emplaced in single magmatic period. All the analyzed rocks are rich in silica and alkaline and weakly peraluminous, having high-K alkali-calcareous and calc-alkaline characteristics. They are enriched in Rb, Th, U, K, etc., but depleted in Ba, Sr, P, and Ti. Both types granites have similar Nd-Hf isotopic compositions and their magmas should originate from partial melting of the Late Archean basement rocks along the southern margin of the North China Craton. The magmatism of A-type granite probably represents the tectonicsthermal event closely related to extension, implying a post-collisional/post-orogenic extensional setting along the southern margin of the North China Craton at ca. 1.80 Ga. 
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    Application of the Weighted Logistic Regression Model in Prediction of Volcanic Rock-Hosted Copper Deposits-Taking the Middle Part of Ning-Wu Basin as an Example
    ZHAO Zengyu, CHEN Huogen, PAN Mao, JIA Gen, LI Xiangqian, XU Shiyin,GUO Gang, ZH
    J4    2016, 22 (1): 105-.  
    Abstract1030)      PDF (1967KB)(1143)       Save

    Application of the Weighted Logistic Regression model in prediction of volcanic rock type Copper deposits in the Middle
    part of Ning-Wu Basin is studied. First, the geological setting of ore-forming processes is analyzed. Three kinds of factors including
    geological body, structure and wall rock alteration are extracted based on the spatial distribution of copper deposits from the geologic
    map. Then, the spatial relationships between Copper mineral occurrence and each evidence factor are analyzed. It is suggested that
    Niangniangshan and Gushan volcanic edifice play an important role in spatial distributions of volcanic rock-hosted Copper deposits.
    The ten evidence raster layers including Longwangshan Formation, Gushan Formation, trachyte porphyry of Gushan volcanic edifice,
    monzonite porphyry of Niangniangshan volcanic edifice, buffers of the structure lines with NE, NW and EW trending, and the alteration
    areas of chalcopyrite, silicide and Limonite are selected. Finally, metallogenic probabilities are calculated using the Weighted Logistic
    Regression model. Four ore-forming prospects, including P1, P2, P3 and P4, are indicated based on the geological conditions of

    metallogenesis and model results. Among these prospecting areas, P1, P2 and P3, which are controlled by Niangniangshan and Gushan
    volcanic edifice, are spread in the northeast direction. P4 extends in the west-east direction and is controlled by Longwangshan volcanic
    edifice. The copper ore bodies are already found in these prospecting areas, suggesting that the results should be generally reliable.

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    Grain-size Characteristics and Environmental Implication of Neogene Red Clays in the Chinese Loess Plateau
    LU Keke, CHEN Zhong, YANG Yanpeng, ZHANG Jialin, ZHAO Zhongqiang, XIA Dinghong, NI Chunzhong, SONG Yinxian, ZHANG Shitao
    Geological Journal of China Universities    2023, 29 (5): 713-725.   DOI: 10.16108/j.issn1006-7493.2022020
    Abstract139)      PDF (1237KB)(312)       Save
    The aeolian origin of red clays in the Loess Plateau has been unanimously recognized. The earliest red clay was found in the late Oligocene and early Miocene, indicating that the arid environment had been formed in the inland northwest of China at the end of Paleogene. The grain size characteristics of red clay in the loess plateau show that the average grain size gradually decreases from the north to the south, indicatin g that the initial monsoon system has been established, and the winter wind played an important role in the transport of aeolian dust. The grain size distribution of red clay indiactes that it is composed of two components. The coarse grain (>20 μm) represents those transported by the near surface wind (winter wind), while the fine grain (<5 μm) represents those transported by the upper westerly wind. The grain size composition characteristics of red clays well record the development and change of atmospheric circulation. Since the end of Oligocene, the average grain size and sedimentation rate of red clays in the west of Liupanshan Mountain increased at 21.3-20.2 Ma, 16.0-13.3 Ma and 8.7-6.9 Ma, which may be related to global cooling and the Qinghai-Tibet Plateau uplift, and the 8.7- 6.9 Ma increase was mainly controlled by global cooling. In the red clay section to the east of Liupanshan, the grain size of variation characteristics shows that the grains deposited during 7.6 Ma to 6.2 Ma or to 5.4 Ma is coarse, indicating that the winter monsoon was strong. After that, the average particle size was fine up to 3.6 Ma, and the deposition rate was low, indicating that the winter monsoon was weak climate environment. From 3.6 Ma to 2.6 Ma, most profiles show an increase in mean grain size, an increase in sedimentation rates, and an increase in both winter and summer monsoon, which indicates to the transition to Quaternary glacial period. The development of the Arctic ice sheet and the uplift of the Qinghai-Tibet Plateau may have contributed to these changes.
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