Most Download articles

Published in last 1 year | In last 2 years| In last 3 years| All| Most Downloaded in Recent Month | Most Downloaded in Recent Year|

In last 2 years

Please wait a minute...


For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails

Select

Zinc Isotopes in Environmental Geochemistry: A Review CHENG Wenhan, WU Meng, ZHAO Yanli, ZHAO Junzhe Geological Journal of China Universities    2024, 30 (03): 312-321.   DOI: 10.16108/j.issn1006-7493.2024036 Abstract （1744）      PDF（pc） （827KB）（2386）       Knowledge map    Save Zinc is one of the essential trace elements for life activities, but in excess, it can cause environmental pollution, ecological toxicity, and harm to human health. Therefore, the study of the environmental geochemical behavior of zinc is the basis for the scientific and rational use of zinc, and it is also a research hotspot in related fields. Zinc has five stable isotopes, and the isotopic composition of zinc varies from different sources. The determination of zinc isotope composition in different  environmental samples provides a new means for studying the environmental geochemistry of zinc. In recent years, with the development of multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS), the study of zinc isotope environmental geochemistry has covered chemical weathering, pollution tracing, paleoclimate reconstruction, and biological processes, and new research fields are constantly expanding. The article provides a detailed overview of zinc isotope analysis methods and their current research status in environmental geochemistry, and looks forward to the future development of zinc isotope environmental geochemistry, in order to promote further development in this field. Related Articles | Metrics | Comments（0）

Select

Mountain Building and Silicate Weathering: A Review and Perspectives LI Shilei, CHEN Yang, CHEN Jun Geological Journal of China Universities    2024, 30 (03): 336-344.   DOI: 10.16108/j.issn1006-7493.2024024 Abstract （2073）      PDF（pc） （913KB）（2380）       Knowledge map    Save The relationship between mountain uplift and climate change has been a prominent focus of research in recent decades. Since the emergence of the famous “uplift-weathering “ hypothesis in the 1980s, which suggests that tectonic uplift of mountains drives climate change over millions of years through silicate weathering, significant attention has been directed towards this concept. Extensive continental denudation and weathering records have been established to test this hypothesis. Despite the majority of these records aligning with the hypothesis, the presence of alternative interpretations complicates direct hypothesis testing. Consequently, numerous studies have explored contemporary weathering processes to better understand this relationship. However, these studies have unveiled that weathering in mountainous regions is not primarily controlled by physical denudation processes and is unlikely to fluctuate in response to tectonic activities. This challenges the fundamental premise of the “upliftweathering” hypothesis. This paper conducts a comprehensive review and analysis to elucidate the reasons for this contradiction. Moreover, it examines the potential of non-local weathering in floodplains as a novel weathering mechanism to resolve this inconsistency. Additionally, it delves into the opportunities and challenges within the realm of non-local weathering research.  Related Articles | Metrics | Comments（0）

Select

Carbon Sequestration Effect and Prospects for Artificial Sinking Enhancement of Marine Diatoms ZHU Huaxi, XUAN Kun, ZHOU Lingling, ZENG Zhihong, GE Chendong, HU Rong Geological Journal of China Universities    2025, 31 (02): 152-164.   DOI: 10.16108/j.issn1006-7493.2024008 Abstract （949）      PDF（pc） （1560KB）（2349）       Knowledge map    Save The ocean, as the largest active carbon reservoir in the Earth surface system, presents a huge potential for carbon sequestration. Owing to their unique physiological structure, widespread distribution, efficient carbon sequestration mechanisms, and strong proliferative capacity, diatoms contribute about 40% of ocean primary productivity and 40% of particulate organic carbon export, playing an important role in the marine biological carbon pump. These organisms exhibit robust carbon sequestration efficiency and exceptional adaptability through powerful CO2 concentrating mechanisms (CCMs) and efficient biophysical and biochemical carbon fixation processes. They also offer opportunities for Carbon Capture, Utilization, and Storage (CCUS), presenting innovative avenues for biological carbon sequestration technology. Identifying and cultivating fast-growing diatom species, optimizing growth conditions, and enhancing photosynthesis efficiency are critical aspects. Current research has employed indoor physiological experiments to decipher factors influencing their physiological activities and carbon sequestration efficiency and further assessed the response of diatoms to global change from the perspective of global biogeochemical cycling. This provides an important theoretical basis for evaluating diatom-mediated natural carbon sequestration and their artificial augmentation prospects. Envisioned as a “microbial carbon sequestration factory”, diatoms hold promise in maximizing carbon sequestration capabilities while generating commercially valuable products. If the cost of carbon sequestration can be effectively reduced, diatom-driven carbon sequestration will be a technologically sustainable solution to support the “Dual Carbon Plan” in the future. Related Articles | Metrics | Comments（0）

Select

Discovery of Volcanic Clay-type Lithium Deposit in Region of Volcanic Rocks Along the Southeastern Coast of China SHAO Xiaoyang, DENG Fei, ZHANG Zhongjin, WANG Rucheng, LU Xiancai, CHE Xudong Geological Journal of China Universities    2024, 30 (04): 409-417.   DOI: 10.16108/j.issn1006-7493.2024031 Abstract （1868）      PDF（pc） （5089KB）（2243）       Knowledge map    Save We report the lithium enrichment in the late Cretaceous Yetang Formation, located in the Shirenbei Basin, northeast of Guangdong Province. The Li2O content is greater than 0.2%, and can be a target for extracting lithium. Comprehensive crosssections of the Shirenbei Basin, geochemical analyses and lithofacies interpretation suggest that the lithium-enriched layers occur in shale, mudstone and siltstone, located in Middle-Upper Yetang Formation; lithium is mainly stored in clay minerals, whose formation is closely related to volcanic activities. It was initially interpreted as a volcanic-type lithium-rich clay deposit. The basin structure provides the environment for sedimentation and concentration of lithium. The layers containing enriched lithium are approximately 226 meters thick in total, and are in great potential for extracting lithium deposit. This discovery provides fclues on investigating large-scale lithium-rich clay deposits related to volcanic activities along the southeast coast of China.  Related Articles | Metrics | Comments（0）

Select

The Occurrence State of Lithium in the Middle Mesoproterozoic Wumishan Formation Lithium-rich Rock Series in Eastern Hebei Province GENG Xiaolei, LI Wei, , WANG Kebing, CAI Yuanfeng, , REN Chao, JI Shichao, WANG Jingzhao, , GAO Yanfeng, WANG Yuguang, TONG Xinen, WANG Ruiqi Geological Journal of China Universities    2024, 30 (06): 694-704.   DOI: 10.16108/j.issn1006-7493.2023072 Abstract （605）      PDF（pc） （5627KB）（2052）       Knowledge map    Save In 2021, Hebei Geological Survey Institute discovered an extraordinary enrichment of lithium in the Middle Mesoproterozoic Wumishan Formation in the eastern Hebei, which is the first time that clay type lithium resources were found in Precambrian strata in China. The lithium-rich rock series has large thickness, wide distribution, stable horizon, Li2O grade of 0.1-0.42 wt%, and has great prospecting potential. As a new lithium-endowed horizon, the occurrence state of lithium is directly related to the exploration and development significance of the clay-type lithium resources discovered this time. By using X- ray diffraction (XRD), thermal analysis (TG-DTG) and Fourier transform infrared spectroscopy (FTIR), it is found that the lithium-rich rocks in the study area are mainly composed of dolomite, quartz and clay minerals such as illite and illite/smectite mixed layers. Through solid state nuclear magnetic resonance spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), clay mineral purification and Na ion exchange experiments, it is revealed that the lithium in the Wushan Formation lithium-rich rock series mainly exists in the illite and illite/smectite mixed layers in the form of isomorphic replacement, and a very small amount of lithium exists in the form of ion adsorption between the clay mineral layers or on the surface. The research results provide important theoretical basis and technical support for the selection, metallurgy and exploitation of clay-type lithium resources in eastern Hebei Province in the future. Related Articles | Metrics | Comments（0）

Select

Equilibrium Isotope Fractionation Effect between Zn-containing Minerals and Aqueous Solution in Contaminated Soils HE Hongtao, GU Yifan, XING Lecai, WANG Yanfang, YANG Yang, CAI Xingping, HE Yuyang Geological Journal of China Universities    2024, 30 (03): 297-311.   DOI: 10.16108/j.issn1006-7493.2024006 Abstract （1931）      PDF（pc） （1441KB）（2048）       Knowledge map    Save Zinc (Zn) isotope fractionation, resulting from multiple physicochemical processes under Earth’s surface conditions, confounds the source identification of pollutants. The determination of Zn isotope fractionation factors between typical Zncontaining minerals and aqueous solutions in contaminated soils is crucial to trace Zn sources using isotopic tools. In this study, we used density functional theory based first principles calculations to investigate the most stable geometries of Zn-containing species, including hydrated Zn2+ complexes, Zn in hydroxy-interlayered minerals (Zn-HIM), Zn-rich phyllosilicates (Talc), Zn-layered double hydroxide (Zn-LDH), and surface adsorbed Zn2+. Based on these optimized configurations, we calculated the equilibrium isotope fractionation factors between the aforementioned structures and Zn2+ in aqueous phases. Our results showed that adsorbed Ⅵ Zn2+ is slightly enriched in 64Zn (Δ66/64Zn=-0.29‰~-0.20‰ ), while adsorbed Ⅳ Zn2+ is enriched in 66Zn (Δ66/64Zn =0.45 ‰~0.73‰ ). Secondary mineral phases are evidently enriched in 66Zn (Δ66/64Zn=0.51‰~1.11‰ ), if Zn transferred to stable crystalline precipitates. Using obtained fractionation factors, we successfully simulated the evolution trends of Zn isotope composition under the influence of single pollution sources (electroplating waste, sphalerite ore, emissions and metallurgical sludge) in equilibrium and Rayleigh fractionation modes. By comparing with available isotope data, these trends facilitate to find out the main source of Zn in contaminated soils. Related Articles | Metrics | Comments（0）

Select

Review on Developments and Applications of Decision Support System in Water Resources Management NAN Tongchao, XIE Xiaoting, YE Yu, XU Teng, SHEN Chengji, WU Jichun, LU Chunhui Geological Journal of China Universities    2025, 31 (03): 263-274.   DOI: 10.16108/j.issn1006-7493.2024042 Abstract （1311）      PDF（pc） （915KB）（1945）       Knowledge map    Save Water resources management decision support system is the application and development of decision support system in the field of water resources. It is a human-computer interaction system developed for the decision-making characteristics of water resources problems. It uses computer and corresponding software (including artificial intelligence, expert system and other technologies) to complete the functions of data extraction, logical reasoning, information processing and management decisionmaking. It can not only help decision-makers to understand the current situation of water resources in time, but also provide more comprehensive, scientific and reasonable integrated management programs for decision-makers to improve the efficiency and reliability of decision-making. This review elucidates and analyzes the current application trends and innovative advancements of Decision Support Systems (DSS) in water resources management (especially in groundwater management) domestically and internationally. At the same time, the paper summarizes prevalent issues existing in the development and application of decision support system. It is pointed out that the lack of basic data and unified standards, the lack of reliability of data-driven decisionmaking, the single function of decision support system, the lack of integrity of decision-making participation, the poor reusability and scalability of the system, and the lack of intelligence are the bottlenecks that need to be broken through in the application and development of decision support system in the field of groundwater resources management. Furthermore, the paper conducts an analysis and projection of its future trajectory in close consideration of the challenges currently confronting water resources management. It is underscored that standardization, integration, modularization, and intelligentization represent the prospective directions for the development of water resource decision support systems. These directions are envisioned to furnish some theoretical support for the establishment of comprehensive regional water resource decision support systems in the future.  Related Articles | Metrics | Comments（0）

Select

Changes in Oceanic Ba Cycle Driven by the Neoproterozoic Oxygenation Event WEI Wei, SUI Peishan, CHEN Tingting, HUANG Fang Geological Journal of China Universities    2024, 30 (03): 288-296.   DOI: 10.16108/j.issn1006-7493.2024009 Abstract （2191）      PDF（pc） （946KB）（1881）       Knowledge map    Save The late Neoproterozoic witnessed an increase in the atmospheric and oceanic oxygen levels, namely the Neoproterozoic Oxygenation Event (NOE), likely resulting in the naissance and radiation of metazoans and the establishment of complex ecosystem. Oceanic oxygenation could change oceanic chemistry, such as species and valence states of Fe, C, and S, and the biogeochemical cycle of Ba in the ocean is strongly controlled by the S species and sulfate concentration. This review introduces how the NOE changed the oceanic Ba cycle: (1) Before the NOE, the oceanic sulfate concentration was low and the oceanic Ba cycle was conservative; (2) during the NOE, the oceanic sulfate increase led to excess Ba enrichments in sediments and formation of massive barite deposits; and (3) after the NOE, the ocean kept over-saturated relative to barite until the terminal Paleozoic and the Ba cycle was controlled by biological productivity afterwards. In addition, this review suggests to use Ba isotope system to reconstruct the oceanic Ba concentration, and indirectly to estimate the oceanic sulfate concentration (oxygenation extent) during the late Neoproterozoic. Related Articles | Metrics | Comments（0）

Select

The Generation of Acid Mine Drainage: Insights from Reactive Transport Modeling and Stable Isotope QIU Wenjie, DU Zhuoran, YIN Ziyue, SUN Yuanyuan, ZHU Xiaobin, WU Jianfeng Geological Journal of China Universities    2025, 31 (01): 1-13.   DOI: 10.16108/j.issn1006-7493.2024091 Abstract （2245）      PDF（pc） （2327KB）（1719）       Knowledge map    Save Acid mine drainage (AMD) resulting from mining activities is a global environmental issue. Investigating the acid generation mechanisms of AMD and the biogeochemical processes affecting the release, migration, and transformation of heavy metals and sulfates provides a scientific basis for quantitatively predicting AMD formation and developing remediation strategies. In this paper, a multiphase reactive transport model for water-gas two-phase flow is constructed based on the TOUGHREACT/EOS3 code to simulate the acid generation process of sulfide minerals (such as pyrite) in tailings impoundment under the influence of atmospheric precipitation and oxygen. It further considers the physical and geochemical reaction processes of associated species in the migration and transformation within the aqueous medium. The reaction network includes the release of H⁺ from the oxidation and dissolution of sulfide minerals, the migration and transformation of iron ions and sulfate, and the pH buffering processes caused by the dissolution and precipitation of major minerals. Finally, by incorporating sulfur stable isotopes into the reactive transport model, the study identifies the bacterial sulfate reduction processes and corresponding sulfur isotope fractionation occurring during the formation of AMD. The model quantitatively assesses the acid production contributions under different oxidation pathways of pyrite, revealing that simultaneously considering the parallel oxidation processes of O₂(aq) and Fe3+ increases the concentrations of acid, iron ions and sulfate. The pH is controlled by the release of H⁺ from pyrite oxidation and the neutralization reactions corresponding to mineral dissolution and precipitation. Stable isotope reactive transport model indicates significant differences in δ34S values under different fractionation kinetic enrichment factor, and using the Rayleigh fractionation model in an open system can greatly overestimate the enrichment factor. This research aids in understanding and predicting the formation and migration processes of acidic water in mining environments, which is crucial for addressing environmental pollution issues caused by mining activities.  Related Articles | Metrics | Comments（0）

Select

Rate, Mechanism, and Geological and Geochemical Effects of Fungi Oromoting Silicate Mineral Weathering LI Zibo, LU Xianca, TENG HuiHenry, LIU Lianwen, QIE Wenkun, PANG Ke, ZHANG Wenxuan, JI Junfeng, CHEN Jun Geological Journal of China Universities    2024, 30 (03): 322-335.   DOI: 10.16108/j.issn1006-7493.2024011 Abstract （1972）      PDF（pc） （2420KB）（1612）       Knowledge map    Save Fungi are widespread and can be found from the Earth’s surface to depths of up to 1.4 km in the continental crust. Based on their ecological habits and nutritional modes, fungi can be categorized as saprotrophic, symbiotic, or parasitic. Hyphae are the basic structural units of fungi. Through their tip-elongated growth and robust metabolic capabilities, fungal hyphae play a unique role in the weathering of silicate minerals, especially those containing nutrient elements. This process regulates essential geological and geochemical processes such as soil formation, mineralization, and the biogeochemical cycling of elements. However, the role of fungi in natural silicate weathering has been relatively overlooked. Our review starts by examining fungal growth patterns, aiming to elucidate their impact on the rate and mechanisms of silicate mineral weathering, as well as their contribution to natural silicate weathering. Through a literature review and in the context of global change, we propose key areas of focus for future research: (1) further quantifying the contribution of fungi to silicate mineral weathering in natural environments, (2) clarifying the coupling of fungal-promoted silicate mineral weathering with geological and geochemical processes, and (3) leveraging functional fungi to improve the efficiency of terrestrial enhanced silicate weathering for carbon removal. These investigations will deepen our understanding of the role of fungi in key surface processes, provide important information for Earth system models (GEOCARB, COPSE, and SCION), enhance the accuracy of predictions regarding the interactions of different spheres in Earth systems, and offer new methods and scientific evidence for the effective carbon sequestration through enhanced silicate weathering. Related Articles | Metrics | Comments（0）

Select

Reconstruction of Global Sea Surface Temperatures during the Early Eocene Climatic Optimum Using Paleoclimate Data Assimilation ZHANG Haoxun, LI Mingsong Geological Journal of China Universities    2025, 31 (03): 275-285.   DOI: 10.16108/j.issn1006-7493.2024041 Abstract （1370）      PDF（pc） （2043KB）（1606）       Knowledge map    Save The Early Eocene Climatic Optimum (EECO, 53.26-49.14 Ma) represents the warmest period of the past 66 million years, with global temperatures reaching their highest levels on a million-year scale. This period serves as a geological reference for future Earth temperatures under the most extreme Shared Socioeconomic Pathways (SSP8.5) scenario in the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Previous studies have reconstructed the global sea surface temperature (SST) state of the EECO using Earth system models and paleoclimate proxies. However, Earth system models often lack constraints on boundary conditions, making it difficult to accurately reconstruct the global SST state of the EECO. Additionally, there are discrepancies between different proxy reconstruction results. This study utilizes an emerging paleoclimate data assimilation approach, conducting simulations with the Earth system model of intermediate complexity, cGENIE. Our 100-member ensemble considers three most important uncertainties: atmospheric carbon dioxide concentration, alkalinity, and rain ratio. We assimilate three types of paleotemperature proxies (TEX86, Mg/Ca and δ18O of planktonic foraminifera) from 35 ocean drilling sites to reconstruct high-precision, globally coupled SSTs during the EECO. The data assimilation yielded a global SST of 30.7 ℃ (95% confidence interval: 28.8-33.0 ℃ ), characterized by significantly improved accuracy compared to prior estimates from Earth system model simulations. Sensitivity experiments confirmed that different types of proxies have a significant impact on the data assimilation reconstruction results: SSTs reconstructed without TEX86 proxy data were lower than those assimilating all proxies, while those without δ18O data were higher. This study provides a high-precision reconstruction of globally coupled SSTs during the EECO hothouse period, offering an accurate geological reference for future climate change. Related Articles | Metrics | Comments（0）

Select

Numerical Simulation and Software Development of Fracture Flow and Reactive Transport Based on Upscaled Discrete Fracture Matrix Model LIU Dianguang, YANG Yun, YUAN Yiliang, DOU Zhi, WU Jianfeng, WU Jichun Geological Journal of China Universities    2025, 31 (01): 14-23.   DOI: 10.16108/j.issn1006-7493.2024089 Abstract （1451）      PDF（pc） （3852KB）（1585）       Knowledge map    Save Reactive transport simulation in fractured media is a prominent and challenging research area in the fields of geosciences and environmental engineering. Traditional equivalent porous media models and discrete fracture networks have certain limitations in accurately characterizing groundwater flow and solute transport processes within complex fracture networks. This paper presents the development of FracRTM, a numerical simulation software for groundwater flow and reactive transport in the fractured media. FracRTM, based on Discrete Fracture Network (DFN) modeling, employs the Upscaled Discrete Fracture Matrix Model (UDFM) to construct continuum meshes and calculate equivalent permeability and porosity. The software integrates open-source reactive transport simulation programs to model the physical and chemical processes of groundwater flow, solute transport, and chemical reactions within fractured-matrix systems. This paper describes the overall design and functional modules of FracRTM , followed by a numerical simulation case study of acid mine drainage migration, which is used to validate the software’s effectiveness. Related Articles | Metrics | Comments（0）

Select

Exploration of New Methods in Marine Strontium Isotope Stratigraphy CAI Yue Geological Journal of China Universities    2024, 30 (03): 253-268.   DOI: 10.16108/j.issn1006-7493.2024015 Abstract （2755）      PDF（pc） （2031KB）（1571）       Knowledge map    Save Strontium Isotope Stratigraphy (SIS) is an important tool for establishing age models for oceanic sedimentary deposits. It has wide applications in many fields including oil and gas exploration and paleoclimate reconstructions. SIS is based on the premise that global seawater is homogeneous relative to Sr isotopes but with variations through time. A key assumption of SIS is that the samples retain the Sr isotope composition of the original seawater where they form. However, diagenesis and loosely attached impurities can alter the Sr isotope composition of the fossil samples, thereby undermining the meaningfulness of the SIS age. Therefore, sample selection and preparation are crucial for obtaining meaningful SIS ages. This article evaluates existing methods for SIS, including sample preparation and Sr isotope analysis. In recent years, to precisely extract the composition of ancient seawater, studies using Nd, Pb, and Li isotopes in carbonates have thoroughly investigated different methods of sample preparation. Based on these technical advances, this paper thoroughly investigated an oyster sample with independent age constraints from the Miocene shallow-marine deposits of the Gulf of Suez, Egypt. By comparing the elemental composition of sequential leachates of the oyster with those of present-day organisms, this paper proposes a new protocol for SIS sample preparation. This paper also compiles and compares the accuracy and precision of Sr isotope data measured using Thermo-ionizing mass spectrometry (TIMS) vs. Multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). While for samples with abundant Sr, the new generation of MC-ICP-MS can reach similar precision and accuracy as the old generation TIMS, for smaller samples and samples that require higher precision, the new generation TIMS is still the best choice for SIS research. Finally, this paper makes some suggestions for Sr analysis on the MC-ICP-MS.  Related Articles | Metrics | Comments（0）

Select

The Origin of Orbicular Granitoids CAO Yufei, LI Shuting, ZHANG Shaobing, HUANG Fang Geological Journal of China Universities    2024, 30 (06): 635-645.   DOI: 10.16108/j.issn1006-7493.2023067 Abstract （962）      PDF（pc） （5289KB）（1517）       Knowledge map    Save Granitoids with orbicular structure are very rare because of their unique orbicular structure. They stand as unique objects to study magma processes. When high-temperature magma contacted or mixed with low-temperature magma, due to their difference in viscosity and temperature, high interfacial tension leads the high-temperature magma to form orbicules in low-temperature magma. The temperature of orbicules decrease rapidly and result in high degrees of supercooling. Induced by exsolution of volatiles or other factors, the orbicules begin to crystallize and branched or feathery crystals are formed. The rapid crystallization in orbicules results in rapid change of local melt and the alternating crystallization of different minerals, forming dark and light rings. During this process, the crystallized minerals can exhibit branched or feathery structures. However, it is still unclear how viscosity and temperature control spheroidization, and how minerals crystallize after spheroidization, and how long the crystallization process lasts. These issues are waiting to be studied and revealed. Related Articles | Metrics | Comments（0）

Select

Petrogenesis of the Biotite Quartz Monzonite from Shangshuiqiao Fluorite Deposit, North Wuyi Area: Constraints from Geochronology and Geochemistry ZENG Xianghui, MENG Delei, ZENG Runling, JIANG Qibao, OUYANG Yongpeng Geological Journal of China Universities    2024, 30 (05): 559-576.   DOI: 10.16108/j.issn1006-7493.2024040 Abstract （919）      PDF（pc） （4598KB）（1451）       Knowledge map    Save Shangshuiqiao fluorite ore is a newly discovered medium fluorite deposit with great exploitation prospect in northern Wuyi area in recent years. However, little research has been carried out on this deposit. In this paper, petrographic, zircon U-Pb chronological and whole-rock geochemical analyses have been carried out on the biotite quartz monzonite from the the Shangshuiqiao fluorite deposit. The zircon LA-ICP-MS U-Pb ages show that the biotite quartz monzonite was formed at  235~236 Ma, which is the product of Indosinian magmatism. According to the geochemical analyses, the biotite quartz monzonite samples are characterized by high alkali (Na2O+K2O), Mg and Fe contents and low P and Ti contents. They have high σ values (2.59 and 3.61) and low A/CNK ratios (0.96 to 1.16), belonging to the typical high-K series with metaluminous to weakly peraluminous. In terms of trace and rare earth elements, the biotite quartz monzonite is enriched in Rb, Th, U, K and light rare earth elements (LREEs), but depleted in Ba, Sr, Nd, Ta, P, Ti and heavy rare earth elements (HREEs), as well as high rare earth elements (ΣREE varying from 356×10-6 to 448×10-6) and weak negative Eu anomalies (Eu/Eu* between 0.61 and 0.76). Besides, the biotite quartz monzonite displays high Zr+Nb+Ce+Y content (varying from 381×10-6 to 546×10-6) and Ga/Al ratio (104×Ga/Al between 2.60 and 3.07), with lower Rb/Sr (0.31 to 0.82), Rb/Ba (0.11 to 0.18) and TFeO/MgO ratios (2.02 to 2.22), belong to post-orogenic (PA type) aluminous A-type granites. In addition, based on the results of geochemical mapping and characteristics of regional magmatism and sedimentation, we suggest that the biotite quartz monzonite from Shangshuiqiao fluorite deposit may be formed in the postorogenic extensional tectonic environment at the end of intracontinental orogeny under the background of multi-plate convergence. During the mineralization stage, the biotite hydrolysis and sericitization of plagioclase in biotite quartz monzonite may provide F and Ca sources for fluorite mineralization. Related Articles | Metrics | Comments（0）

Select

Oceanic Lithium Cycling and Implications for Carbon Cycle CAO Cheng Geological Journal of China Universities    2024, 30 (03): 269-287.   DOI: 10.16108/j.issn1006-7493.2024022 Abstract （1990）      PDF（pc） （3114KB）（1425）       Knowledge map    Save How the carbon cycle influences the atmospheric carbon dioxide level is of a major concern for Earth’s habitability.The oceanic lithium (Li) cycle can be used to trace carbon cycle because both cycles are controlled by chemical weathering, hydrothermal-seafloor interaction, and marine clay authigenesis which also known as reverse weathering. The variations in seawater Li isotope compositions posit changes in the sink and source processes such as continental weathering intensity and/or rate as well as reverse weathering rate. This paper reviews the global cycle of oceanic lithium and the mass balance for seawater lithium isotopes, focusing on the present-day fluxes and associated isotope fractionation mechanisms. Challenges still remain to better constrain the budgets as well as isotope fractionation factor especially in hydrothermal alteration and reverse weathering. The review also extends to the use of seawater li isotope records in tracing carbon cycle during climate events and critical time periods in the earth history. Collectively, this review highlights the potential as well as limitations of utilizing seawater Li isotope records to trace global carbon cycle in deep time.  Related Articles | Metrics | Comments（0）

Select

Experimental Study on Seepage and Heat Transfer of A Single Fracture in Sandstone during Shallow Geothermal Extraction WU Hongtao, WANG Huimin, ZHENG Huifeng, SHENG Jinchang, HUANG Tairen, TIAN Jiali, SHENG Danna Geological Journal of China Universities    2024, 30 (05): 593-602.   DOI: 10.16108/j.issn1006-7493.2023056 Abstract （705）      PDF（pc） （2395KB）（1422）       Knowledge map    Save The development and utilization of shallow geothermal energy is related to the successful achievement of the “doublecarbon” target. The study on seepage and heat transfer characteristics of the rock fracture in the target reservoir is critical to the effectiveness of the groundwater source heat pump system. However, most of the previous studies on seepage and heat transfer in fractures considers a single factor such as rough surface, flow velocity, confining pressure, temperature for the evaluation of its heat transfer efficiency. The understanding of the evolution mechanism of seepage and heat transfer and its contribution degree by the change of shallow geothermal reservoir (confining pressure and rock temperature) at multiple flow rates have not been systematically investigated. Therefore, based on a self-developed seepage and heat transfer system of fractured rocks, this paper carried out the seepage and heat transfer test under multiple flow rates for sandstone with a single fracture. Subsequently, the evolution characteristics of single fracture seepage and heat transfer under multiple flow rates were analyzed. Finally, the influenced mechanism and contribution degree of sensitive parameters (confining pressure and rock temperature) in shallow geothermal on seepage and heat transfer were discussed. The test results show that: (1) The trends of outlet water temperature and convective heat transfer coefficient with the increase of water flow rate have obvious transition stages. (2) The increase of confining pressure leads to the fracture closing and the thinning of flow boundary layer, while the increase of temperature gradient causes a higher outlet water temperature and convective heat transfer coefficient due to the increase of heat flux density. (3) The contribution of rock temperature is significantly higher than that of confining pressure. Especially when the temperature increases from 60 ℃ to 70 ℃ , the convective heat transfer coefficient increases dramatically. Related Articles | Metrics | Comments（0）

Select

Anomaly Data Identification Method for Geological Disaster Monitoring Based on Generate Adversarial Network LIU Jiangcheng, HAO Guangyao, TAO Hong, XU Yanyan, WANG Heng, JIANG Xianhui, CHEN Qun Geological Journal of China Universities    2025, 31 (02): 174-184.   DOI: 10.16108/j.issn1006-7493.2024002 Abstract （596）      PDF（pc） （769KB）（1410）       Knowledge map    Save Reliable geological hazard warning depends on accurate sensing data. In order to solve the problems of large noise and long time sequence characteristics of geological monitoring sensor data, we propose a method to identify abnormal data of geological disaster monitoring based on generative adversarial network. Firstly, the RandAugment algorithm is used to enrich the diversity of training data and improve the robustness to noise. Secondly, multi-head self-attention mechanism is used to extract long time series features, and the stability of early warning performance is improved by adversarial training mechanism. Experiments on four real-time series sensor data streams extracted from hidden geological disaster points in Shaanxi Province show that the proposed method has a 5%-10% improvement in AUROC and F1 indexes, compared to widely used machine learning methods.  Related Articles | Metrics | Comments（0）

Select

Numerical Modeling of Groundwater Dynamic Response to Agricultural Irrigation in a Typical Arid Area WANG Beida, SONG Jian, YIN Ziyue, LIN Jin, WU Jianfeng Geological Journal of China Universities    2025, 31 (01): 92-103.   DOI: 10.16108/j.issn1006-7493.2024010 Abstract （1611）      PDF（pc） （4614KB）（1383）       Knowledge map    Save Researching the impact of agricultural irrigation on the groundwater dynamic under different crop growth conditions in arid and semi-arid area holds significant practical importance for the rational development and utilization of regional groundwater. Using the MODFLOW-NWT program and unsaturated zone simulation subroutine package UZF1 in GMS software, a numerical model was established for the northern bank of the Kaidu River in the Yanqi Basin. The model was calibrated using daily groundwater level data. Water balance analysis was also conducted. Water requirement for five typical crops (peppers, tomatoes, wheat, sugar beets, and corn) was computed using the crop coefficient method. The calibrated groundwater model was used to simulate the effects of agricultural irrigation on the groundwater depth dynamic under different planting scenarios. The results show that planting the high-water-consumption sugar beets corresponds to the greatest average groundwater depth, while planting wheat results in the smallest average groundwater depth. Average Groundwater depth are similar when planting tomatoes, peppers, and maize. During sugar beets cultivation, the average groundwater depth is 0.85 meters greater than during wheat cultivation. With a 100-millimeter-increase in water demand, the average groundwater depth increases by 0.31 meters during the growing season. It indicates that crop water requirement is a crucial factor affecting groundwater level fluctuation in study area. The finding can provide a scientific guidance for the sustainable management of water resources and the formulation of agricultural planting strategy of arid and semi-arid area.  Related Articles | Metrics | Comments（0）

Select

Heat Flow and Deep Temperature Distribution in Kuqa Foreland Basin, Northwestern China FENG Guanzhong, LIU Shaowen, ZHU Chuangqing, LI Xianglan Geological Journal of China Universities    2024, 30 (04): 460-475.   DOI: 10.16108/j.issn1006- 7493.2023021 Abstract （1522）      PDF（pc） （6800KB）（1383）       Knowledge map    Save Geothermal regime of the sedimentary basins is key for understanding the formation and evolution of the basins and assessing hydrocarbon and geothermal energy, and has attracted much attention from the academia and industrial circles. Kuqa Foreland Basin, located between the Tarim Basin and Southern Tianshan Mountain, is one of major hydrocarbon exploration targets in China, and accurate knowledge of geothermal regime of this basin is beneficial for hydrocarbon potential assessment. Here we integrate updated steady-state temperature logs and oil testing temperature, with thermal properties data, to decipher the thermal characterization of the Kuqa Foreland Basin. The geothermal gradient of the basin ranges from 17.3 to 25.7 ℃ /km, with an average of 21.5±2.6 ℃ /km; while the heat flow varies from 27.4 to 57.9 mW/m2, with a mean of 40.9±7.2 mW/m2. The range and average of estimated formation temperatures at 1000-6000 m in the basin are 26-49 ℃ (36±4.6 ℃ ), 42-82 ℃ (59±7.5 ℃ ), 64-113 ℃ (82±10.3 ℃ ), 85-127 ℃ (102±11.6 ℃ ), 98-140 ℃ (119±12.8 ℃ ) and 110-155 ℃ (133±13.9 ℃ ), respectively. Generally, the present-day thermal state of the Kuqa Foreland Basin is relatively low and the thermal pattern is characterized by hot in the north and east, cold in the south and west, which is attributed to the east-west differences in the thickness of the Cenozoic sediments and the lateral variations in the intensity of active deformation associated with the far field effects of the Indo-Asian continental collision. The large thickness of the sediments in the western part of the basin, which forms the thermal blanketing effects owing to their low thermal conductivities, preventing the transport of heat from the deep to the surface. In addition, the active deformation in the eastern part of the basin is more intense, and the friction heating effect of fault movements is obvious. These two factors are combined to account for the observed present-day geothermal field pattern of Kuqa Foreland Basin. Related Articles | Metrics | Comments（0）

Select

pH Swing-Evaluation of Economic Potential of Mineralized Carbon Fixation Process of Steel Slag XIE Kui, ZHAO Liang, ZHU Chen, FENG Henan, SUN Jiajia, ZHOU Yiyang Geological Journal of China Universities    2024, 30 (04): 476-484.   DOI: 10.16108/j.issn1006-7493.2023034 Abstract （1629）      PDF（pc） （1219KB）（1364）       Knowledge map    Save The CO2 mineral sequestration-based ammonium slag recycling carbon sequestration process has promising economic potential and CO2 emission reduction benefits, which can help steel companies achieve high-value comprehensive utilization of steel slag solid waste and waste resources containing CO2 flue gas. Raw material loss, reaction time and impurity ion behavior directly affect the operation cost and product quality of the process, and ultimately determine its application value. In this study, the economic potential of the steel slag ammonium salt recycling carbon fixation process was evaluated through laboratory scale test data, and suggestions were made for process parameter determination and optimization directions from the cost control perspective. The results show that the freshness of the solution remains basically unchanged during 10 cycles of leaching solution, and the main reason for the loss of raw materials is the loss of solution volume; the precipitation process CO2 flow rate reaches 15-20 L/min when the precipitation time drops to 20-30 min, at this time the precipitation process is not a limiting factor of the process operation rate; no obvious enrichment of impurity ions is seen in the circulating solution, and the precipitated calcium carbonate products of ten rounds of reactions are in line with industry standards; the CO2 reduction factor of this process to produce precipitated calcium carbonate is 1.543; the profit of this process to reduce 1 ton of CO2 is 1325.25 RMB, and the profit can reach 1654.74 RMB by reducing the solution loss, which has significant economy.  Related Articles | Metrics | Comments（0）

Select

Niobium Mineralization in the Miaoya Alkaline Complex, Hubei Province: Constraints from Rutile Mineralogy and Geochronology YING Yuancan, CHEN Wei, LIU Jiajun, YANG Fan, JIANG Shaoyong Geological Journal of China Universities    2024, 30 (03): 345-361.   DOI: 10.16108/j.issn1006-7493.2024019 Abstract （2679）      PDF（pc） （6817KB）（1350）       Knowledge map    Save The Miaoya alkaline complex is mainly composed of syenite and carbonatite enriched in Nb and REE, with a verified Nb2O5 reserve of 0.93 Mt @ 0.12%. It is the second largest carbonatite-hosted Nb-REE deposit in China, second only to Bayan Obo. Previous studies have focused on the genesis of carbonatite and the process of REE enrichment, but the occurrence and enrichment mechanism of Nb in syenite are still unclear. Based on field geological surveys, detailed petrography, mineral chemistry, and U-Pb dating of the Nb-bearing minerals in syenite were obtained using TIMA, EMPA and LA-ICP-MS analyses. The results show that the main Nb-bearing mineral in the Miaoya syenite is rutile, which can be divided into magmatic and hydrothermal generations based on texture and chemical composition. Magmatic rutile is rare, while hydrothermal rutile is common in various syenites, mostly disseminated along the edges or fissures of primary rutile or closely associated with biotite and ilmenite. Magmatic rutile shows low contents of Nb2O5 (1.43%~2.56%), FeO (0.74%~1.01%), and other trace elements (e.g., Ta, Cr, V, W, Mo, Sb); while hydrothermal rutile has variable enrichments of Nb2O5 (3.48%~20.68%), FeO (1.18%~6.92%), and other trace elements. In-situ U-Pb dating of rutile illustrates that the formation age of magmatic rutile is 446±21 Ma, while the formation age of hydrothermal rutile is 240±19 Ma, indicating that Nb mineralization in syenite experienced initial enrichment during the early Paleozoic magmatic stage and secondary enrichment during the Triassic hydrothermal metasomatic stage. In summary, we believe that Nb enrichment and mineralization in the Miaoyao complex are controlled by both magmatic and hydrothermal processes. During the early Paleozoic magmatic stage, niobium within syenite is mainly hosted by rutile, biotite and Ti-bearing minerals (e.g., ilmenite); in the Triassic hydrothermal metasomatic stage, hydrothermal fluids can decompose biotite to form secondary Nb-rich rutile and columbite, or metasomatize primary rutile and ilmenite to generate hydrothermal Nb-rich rutile.  Related Articles | Metrics | Comments（0）

Select

Study on Soil Suction Measurement Method Using PSYPRO Dew Point Water Potential Technique ZHANG Dazhan, TANG Chaosheng, XU Jinjian Geological Journal of China Universities    2024, 30 (04): 451-459.   DOI: 10.16108/j.issn1006-7493.2023020 Abstract （1414）      PDF（pc） （1760KB）（1324）       Knowledge map    Save Soil suction measurement is crucial for the stability assessment of geotechnical engineering, real-time and accurate measurement of suction changes in soil from saturated to dry state has always been a hot topic and challenge in the field of unsaturated soil mechanics. Dew point water potential technique is a novel measurement method of soil suction. This paper detailly introduces the working principle of the PSYPRO dew point water potential meter and the significance of the required debugging parameters, and combines the calibration test and the evaporation test to give the optimal time parameter setting recommendations for the PSYPRO dew point water potential meter to measure different soil suction intervals. In this paper, the PST-55 psychrometer was firstly calibrated with different concentrations of NaCl solutions and the correction coefficient was obtained, and then the laboratory soil evaporation test was carried out, the PST-55 psychrometer and ML3 soil moisture sensor were used to measure the drying process. The changes in soil suction and water content verified the feasibility and accuracy of dew point water potential technique for real-time continuous monitoring of soil suction.  Related Articles | Metrics | Comments（0）

Select

Using Vanadium Isotopes to Constrain the Proportion of Lunar-forming Material SHI Zhen, QI Yuhan, HUANG Fang, DING Xin Geological Journal of China Universities    2024, 30 (03): 371-378.   DOI: 10.16108/j.issn1006-7493.2023065 Abstract （2092）      PDF（pc） （1037KB）（1253）       Knowledge map    Save The classic giant impact model is currently the most widely accepted hypothesis for explaining the lunar formation process. It posits a collision between a proto-Earth in its late accretion stage and a Mars-sized impactor named Theia. According to this model, the majority of the Moon’s material is derived from Theia. However, there is still a lack of precise constraints on the contribution percentage of the impactor to the lunar mass. In this study, high-precision measurements of mantle peridotites and komatiites are employed to reevaluate the V isotope composition of the Bulk Silicate Earth (BSE). Unlike previous studies, the new data indicate δ51VBSE=-0.91±0.02‰（2SE, n=18）. We incorporated this into a two-component mixing model for the Earth-Moon system, considering a system with pre-impact (proto-Earth, Theia) and post-impact (Earth, Moon, escaping mass) components. The best estimate for the mass fraction of Theia in the present Moon ranges from 73% for MTheia=0.8MMars to 83% for MTheia=0.45MEarth This represents a reduction of approximately 5% in Theia’s contribution compared to earlier studies. These findings provide more reliable parameters for the classic collision model, contributing to a deeper understanding of the lunar formation process. Related Articles | Metrics | Comments（0）

Select

Application of HydroSHEDS Dataset in Climate Change and Biodiversity Evolution HOU Zixi, ZHENG Dongyu, XIANG Fang, BAI Jie, CHEN Anqing, MA Chao, HOU Mingcai Geological Journal of China Universities    2025, 31 (02): 238-254.   DOI: 10.16108/j.issn1006-7493.2024023 Abstract （608）      PDF（pc） （4646KB）（1222）       Knowledge map    Save Climate and biodiversity changes affect the environment, and they are also the consequences of environmental change. The HydroSHEDS dataset is a multi-source of global natural-human dataset that is based on basic hydrological information from basins, which forms a nested basin dataset with 12 levels. This dataset provides valuable support for studying how environmental characteristics of basins impact climate change and species distribution. The study investigates the content and application examples of the dataset, and then summarizes the research significance of the HydroSHEDS dataset for climate changes and biodiversity evolution in modern and Quaternary. The results indicate that: (1) HydroSHEDS v1 contains basic global basin information, including flow directions, flow accumulation, and river networks. It incorporates 6 categories (hydrology, physiography, climate, soil & geology, land cover & use, and anthropogenic influences) which comprise 56 variables, a total of 281 attributes on a global scale. (2) By utilizing the fundamental or core data of HydroSHEDS, modern and deep-time climate change research can be conducted, including investigating the impacts of climate changes on other components of the surface system by model simulating, calculating the relationship between basin attribute characteristics and the changes of greenhouse gas concentrations, and the quantitative assessment of proxy data to improve the reconstruction of precipitation and evaporation within the climate model. (3) By directly overlaying or integrated weighting analysis, the environmental attributes of HydroSHEDS dataset could analyze the impacts on species habitats or actual ranges, and simulate their potential distributions in the present and future. (4) Although HydroSHEDS can be used as a prerequisite for the analysis and application of surface systems, the timeliness and sequence of the environmental attribute information recorded by this dataset are not emphasized, rendering this dataset as suitable auxiliary data in time series research. Enriching the time series data of HydroSHEDS is expected to provide valuable support for predicting future climate change and biodiversity evolution and deep-time research. Related Articles | Metrics | Comments（0）

Select

Macroscopic and Spectroscopic Study on Phosphate Adsorption by Ce-Al Oxide NIE Hongda, REN Chao, LI Wei Geological Journal of China Universities    2024, 30 (05): 505-513.   DOI: 10.16108/j.issn1006-7493.2023046 Abstract （934）      PDF（pc） （2775KB）（1199）       Knowledge map    Save Eutrophication caused by excess phosphate in water bodies is an important issue in China and many countries (regions) around the world. Therefore, it is crucial to investigate the environmental geochemical behavior of phosphate and to explore phosphorus removal techniques and principles. In this study, a Ce-Al oxide was synthesized as the adsorbent material to investigate the adsorption behavior and mechanism of orthophosphate. The effects of system parameters such as reaction time, initial phosphate concentration, pH and ionic strength on the phosphate adsorption by the Ce-Al oxide were examined. The results showed that the phosphate adsorption reached equilibrium within 24 hours; the adsorption isotherm (pH=7) was best fitted by Langmuir adsorption mode, yielding a maximum adsorption amount of 75.5 mg·g-1; and importantly the adsorption was insensitive to pH and maintained a high efficiency in the studied pH range (i.e. pH=3-10). This study further employed zeta potential measurement, microscopic analyses (SEM and TEM) and spectroscopic methods (XRD and XPS) to investigate the phosphate adsorption mechanisms by the Ce-Al oxide. It can be concluded that surface precipitation and inner-sphere adsorption dominates the phosphate adsorption mechanisms by the Ce-Al oxide. The study demonstrates that the Ce-Al oxide is a candidate material for phosphate removal. Related Articles | Metrics | Comments（0）

Select

Reconstructing Humidity Using the Triple Oxygen Isotopes of Pedogenic Carbonates DA Jiawei Geological Journal of China Universities    2024, 30 (03): 241-252.   DOI: 10.16108/j.issn1006-7493.2023069 Abstract （2058）      PDF（pc） （1107KB）（1168）       Knowledge map    Save The secondary carbonate formed during the soil formation process (pedogenic carbonate) is a crucial material in paleoclimate studies. In previous research, it has been widely used to reconstruct atmospheric CO2 concentrations, paleoaltimetry, the evolution of regional paleovegetation (C3, C4 plants), precipitation, and temperature. However, like most other paleoclimate indicators, proxies based on pedogenic carbonate (such as stable carbon and oxygen isotopes, trace elements, etc.) are influenced by multiple climate factors, resulting in ambiguity. Therefore, obtaining reliable paleoenvironmental information requires the integration of multiple indicators. With the recent development of isotope testing methods, in addition to the traditional 18O/16O, triple oxygen isotope analysis (17O/16O) has been increasingly applied in paleoclimatology. Pedogenic carbonates inherit the oxygen isotope signal of soil water. Combined with the carbonate-clumped isotope temperature, the 17O anomaly of soil water can be reconstructed. The soil-water-Δ′17O is mainly controlled by the evaporation process, thus providing information about past humidity. This article provides a detailed introduction to the theoretical basis of pedogenic carbonate triple oxygen isotopes. It quantitatively discusses the impact of various climate factors on pedogenic carbonate triple oxygen isotopes using existing soil water triple oxygen isotope models. Related Articles | Metrics | Comments（0）

Select

Hydroclimate Changes in Southwestern China Over the Past 800 Years and its Dynamics ZHAO Bin, CUI Yingfang, KONG Xinggong, ZHAO Kan, WANG Yongjin Geological Journal of China Universities    2024, 30 (06): 747-755.   DOI: 10.16108/j.issn1006-7493.2023063 Abstract （704）      PDF（pc） （7662KB）（1155）       Knowledge map    Save Southwestern China is a high-risk area of drought. However, hydroclimate behavior and its mechanism on various timescales in southwestern China are still unclear, largely due to scarce long-term high-resolution hydrological reconstructions. Moreover, the speleothem-based oxygen isotope record shows an ambiguous relationship between Asian summer monsoon variation and regional hydrological change. Here, we present a nearly 800-yr-long (1180-1969 AD) annually resolved and accurately dated regional hydroclimate record based on annual laminae thickness data from a stalagmite (NO. DX1) in Dongge Cave, Guizhou Province. The regional climatic conditions are dominantly influenced by the Asian summer monsoon and the Intertropical Convergence Zone (ITCZ). In the continuously-growing section (from 0-58.2 mm), regular laminations can be observed under a microscope. The microscopic features of the lamina resemble those from Shihua and Hulu caves in the monsoonal regions of China. Therefore, we obtain a layer-counting timescale and an annual laminae thickness record from 1180 to 1969 AD. The close similarity between the annual laminae thickness and δ13C records suggests that annual laminae thickness of stalagmite DX1 can serve as a proxy for regional hydroclimate. Centennial-scale hydroclimate changes are broadly similar to the Northern Hemisphere (NH) temperature variations, with a significant drought event (-1540-1630 AD) during the Little Ice Age (LIA), supporting that the NH temperature has an important influence on low-latitude hydrological changes, via meridional shifts of the ITCZ. The mathematical analyses reveal that the regional hydrological changes display significant -3-year and -7-year periodicities (accounting for -44% of the total variance), likely related to the interannual El Niño-Southern Oscillation (ENSO) variations. In addition, the 31-yr running biweight variance for the regional hydroclimate gradually decreased from the Medieval Warm Period to the LIA, reached the minimum during the coldest LIA interval (-1540-1630 AD), then gradually increased, and became unusually high during the Current Warm Period. This hydroclimate variance is largely consistent with the reconstructed ENSO variance and further modulated by secular NH temperature background states. Our observation implies that the ENSO and low-latitude hydrological variance will increase, and the frequency and amplitude of extreme climate events will increase under the scenario of continuous global warming. Related Articles | Metrics | Comments（0）

Select

Using the Thickness of Delta Foredeposits to Restore the Maximum Paleo-water Depth of Lakes: A Case Study of Qinnan Sag in Bohai Bay Basin and Huizhou Sag in Pearl River Mouth Basin DANG Zhaoqing, CHEN Ying, LYU Chengfu, BAI Zhizhao, XIAO Yueye, ZHOU Qianshan Geological Journal of China Universities    2024, 30 (06): 726-736.   DOI: 10.16108/j.issn1006-7493.2023058 Abstract （697）      PDF（pc） （8320KB）（1111）       Knowledge map    Save Water depth plays a decisive role in the redox conditions of a basin and plays an important role in the enrichment and preservation of organic matter in sedimentary basins. Previous studies mainly relied on paleontology, element geochemistry, stratigraphic thickness, and other methods for qualitative and semi-quantitative palaeodepth restoration. However, these methods have a high dependence on original samples and low prediction accuracy and are not suitable for Palaeogene Lake basin palaeodepth restoration in offshore basins. In this study, the depth of paleowater is mainly restored based on the thickness of the delta for deposits in seismic profiles. By using this method, the maximum palaeobathymetric during the sedimentary period of the third Member of the Shahejie Formation of the Eocene in Qinnan west subsag of Bohai Bay Basin is 595 m, and the maximum paleowater depth during the sedimentary period of Wenchang Formation in the southwest of Huizhou Sag of Pearl River Mouth Basin is 526 m. Combined with previous research results, it is found that the rate of sag-controlling fault activity is strong in the third Member of the Shahejie Formation period of Qinnan Sag and the Wenchang Formation period of Huizhou Sag, and they are during the strong rifting of the basin, which controls the formation of deep water lake basins. During this period, many Sags in Bohai Bay Basin and Pearl River Mouth Basin are in deep-water-ultra-deepwater environments, so it is inferred that the deep water environment is the result of strong fault activity. Then the redox conditions of the lake basin are controlled, and more organic matter is preserved in the lake basin to form high-quality source rocks.  Related Articles | Metrics | Comments（0）

Select

Petrography and Mineralogy of Lunar Magnesian Anorthositic Meteorite Northwest Africa 8599 ZHANG Zhenguang, ZHANG Lang, DU Tianran, ZHAO Kai, ZHANG Aicheng Geological Journal of China Universities    2025, 31 (03): 286-300.   DOI: 10.16108/j.issn1006-7493.2024047 Abstract （1082）      PDF（pc） （3895KB）（1106）       Knowledge map    Save Northwest Africa (NWA) 8599 is a lunar breccia meteorite found in Northwest Africa. We performed detailed petrographic and mineralogical study on this lunar meteorite. Our observations reveal that NWA 8599 is an olivine-rich magnesian anorthositic noritic breccia, with abundant mineral fragments and minor fine-grained magnesian anorthosite clasts. Our NWA 8599 sample contains a coarse-grained highly magnesian olivine fragment (Fo=84-87), which is closely associated with highly magnesian pyroxene (Mg#=85-89) and geikielite (Mg#=52-54). The geikielite grains in NWA 8599 are reported for the first time among lunar meteorites and mission-returned lunar samples. The CaO contents in the highly magnesian olivine and thermobarometric calculations of pyroxenes indicate that the highly magnesian mineral assemblage is likely derived from a highly magnesian rock from deep crust of the Moon. Our results show large variations in modal abundance and grain size for the magnesian anorthosites in NWA 8599, indicating diversity of the magnesian anorthositic lithologies in the Moon. We suggest that the magnesian anorthosites may be produced by variable degrees of assimilation of primordial ferroan anorthositic crust by mantlederived magnesian melt during lunar mantle overturn. Related Articles | Metrics | Comments（0）