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Journal of Earth Science 2024年第3期35卷 812-827页

作者： Peiwen Liu Xiaozhong Ding Yanxue Liu Jibiao Zhang Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of Civil and Hydraulic Engineering Xichang UniversityXichang 615000China

In situ zircon U-Pb geochronological and Lu-Hf isotope studies of detrital zircons from Late Mesoproterozoic to Early Neoproterozoic sedimentary units on the southwestern margin of the Yangtze Block have important implications for the tectonic evolution of the Yangtze *** Huili Group contains zircons whose ages are mainly Late Archean to Mesoproterozoic(2650-2450,2100-1800,and 1350-1150 Ma).The Dengxiangying Group has one major age population of 1900-1600 Ma,and two subordinate age populations of 1350-1100 and 2300-2000 *** Group sedimentary rocks have a zircon age population mainly in the range of 970-850 Ma,contemporaneous with the ages of widespread arc-related magmatism in the western Yangtze *** these results with previous work,the Huili and Dengxiangying groups were most likely deposited during ca.1160 to 1000 Ma in an intra-continental rift basin setting,while the Yanbian Group accumulated during>920 to 782 Ma in a back-arc basin setting at the southwestern margin of the Yangtze *** addition,all these results further suggest a tectonic transition from a continental rift basin to a convergent environment at the southwestern margin of the Yangtze Block at 1000-970 Ma.

关键词： Late Mesoproterozoic Early Neoproterozoic zircon U-Pb age Lu-Hf isotope southwestern Yangtze Block geochronology

Cassiterite U-Pb dating of the Yelonggou pegmatite-type lithium deposit in western Sichuan and its metallogenic age constraints

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china Geology 2024年第1期7卷 153-156页

作者： Xiang-yuan Yue Qian Zhang Jun-jun Zhang Wei Zhang Jing Zhang Zhi-quan Jia Li-ping Luo Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological SciencesChengdu610041China Shandong Lunan Geology and Exploration Institute(No.2 Brigade of Shandong BGMR) Jining272100China Sichuan Shudao Advanced Material Science Group Co.Ltd. Chengdu610041China No.3 geological Brigade of Sichuan Province Chongzhou611230China

*** Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type deposits,for which accurate dating of pegmatite formation and mineralization is *** Songpan-Ganzi orogenic belt is a major rare metal metallogenic belt in china,hosting many important pegmatite-type Li deposits,including the Lijiagou,Dangba,Jiajika,Yelonggou,Cuola,and *** age data(mica Ar-Ar and zircon/cassiterite U-Pb)from these Li deposits are sparse,ranging from 210 to 152 ***,obtaining reliable zircon U-Pb dates can be a challenge due to the strong decidualization in *** a result,the formation and mineralization ages of these rare metal pegmatites remain controversial,which hampers the development of pegmatite-type metallogenic model for the Songpan-Ganzi orogenic belt.

关键词： dating metallogenic zircon

Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,china:A review

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china Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao Wang Zhong-jian Zha Hai-jun Bai Jiang Wang Development and Research Center of china geological survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Institute of geological surveying and Mapping Technology of Anhui Province Hefei 230022China Third geological Brigade of Hebei Bureau of Geology and Mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in china containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North china Craton Mineral exploration engineering

Evolution of the Mangrove Wetland since the Holocene:Current Progress and Future Perspectives

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Journal of Earth Science 2024年第5期35卷 1669-1678页

作者： Xueyan Yan Xianzhong Ke Qinghua Li Yiqun Gan Xianjun Xie Yamin Deng geological survey China University of GeosciencesWuhan 430074China Wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China School of Environmental Studies China University of GeosciencesWuhan 430074China

Mangrove wetlands are among the four most productive tropical and subtropical *** are also a core component of the coastal blue carbon ecosystem,which is of great ecological significance to human beings,plants,animals,and the global carbon *** has been a global decrease in the distribution of mangrove forests,and their ecological function has gradually degenerated since the *** from coastal mangrove wetlands can provide records of climate change and human activities,and multiple proxies including palynology,leaf fossil,biomarkers,DNA,phytolith and stable isotopes,can be used to reconstruct the evolutionary stages of paleo-mangroves and to identify the effect of natural processes and human activities on the distribution and evolution of *** information can provide theoretical support for mangrove protection and for improving carbon sequestration *** paper summarizes and compares the multiple proxies for mangrove reconstruction,reviews progress in the study of natural succession of global mangroves since the Holocene,expands on the influence mechanisms of human activities on mangrove growth and development and uses past information to lay a foundation for a model to predict future mangrove development.

关键词： mangrove Holocene multiproxy sedimentary environment climate change environ-mental geology

Co-occurrence, sources and co-enrichment mechanism of arsenic, fluoride in groundwater from Huaihe River Basin, china

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Emerging Contaminants 2024年第1期10卷 90-99页

作者： Naizheng Xu Lin Liu Tan Mengjiao Xiaohu Tao Liang Li Hesheng Wang Jianshi Gong china geological survey Nanjing Center Nanjing210016China Key Laboratory of Watershed Eco–geological Processes Ministry of Natural ResourcesNanjing210016China Chinese Academy of geological Sciences Beijing10037China china Science and Technology University Hefei230026AnhuiChina

Arsenic(As),fluoride(F^(−))are both ubiquitous in groundwater,and co-exposure to these elements through contaminated drinking water may cause detrimental effects on human health more in comparison with individual ***,F^(−)co-occurrence in groundwater of the inland plain in Huaihe River Basin,china is a major concern,where inhabitants are rely on groundwater as the leading water source for drinking to *** work employs an approach of hydrochemical analysis and modelling to identify the possible origin of As and F^(−),to analyze co-enrichment mechanism,and to estimate the associated exposure *** results shows presence of elevated As and F^(−)concentrations is an important factor affecting groundwater quality from 62 groundwater *** recorded As concentrations vary from 0.23 to 20.40μg/L,with a mean of 5.95μg/L,F^(−)concentrations vary from 0.54 to 2.60μg/L,with a mean of 1.29 mg/L,and 8%of samples are simultaneously above their permissible limits in drinking water by the *** with As,F^(−)co-contamination is occurred within reducing and alkaline aquifers,and its chemical type is HCO_(3)–*** hydrochemical processes involved in the co-contamination are reductive desorption,evaporation,and ion exchange,which are controlled by local geology,geomorphology,and *** As is derived and released by reductive desorption and F^(−)is mainly originated by fluorite *** As,F^(−)are geogenic sources,and the mechanisms for co-contamination are associated with high elemental abundance,flat terrain,alkaline and reductive groundwater *** research provides a case study about groundwater As,F^(−)co-contamination,which may be enhance understanding the co-enrichment mechanism in semi-humid areas.

关键词： Arsenic Fluoride Co-contamination Source and co-enrichment processes Huaihe River Basin,china

Structural,^(40)Ar/^(39)Ar Geochronological and Rheological Feature Analysis of the Guoxuepu Shear Zone:Indications for the Jitang Metamorphic Complex in the Northern Lancangjiang Zone

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 32-49页

作者： FENG Yipeng WANG Genhou WANG Shulai LI Dian WANG Huan LU Yang LIU Han ZHANG Peilie Beijing Institute of Geology for Mineral Resources Co. Ltd.Beijing 100012China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China College of Earth Sciences Chengdu University of TechnologyChengdu 610059China Rock Analysis Laboratory Regional Geology Survey Institute of Hebei ProvinceLangfangHebei 065099China Chengdu Center China Geology SurveyChengdu 610081China

The Jitang metamorphic complex is key to studying the tectonic evolution of the Northern Lancangjiang *** structural-lithological mapping,structural analysis and laboratory testing,the composition of the Jitang metamorphic complex was *** macro-and microstructural analyses of the ductile detachment shear zone(Guoxuepu ductile shear zone,2–4 km wide)between the metamorphic complex and the overlying sedimentary cap show that the shear sense of the ductile shear zones is *** presence of various deformation features and quartz C-axis electron backscatter diffraction(EBSD)fabric analysis suggests multiple deformation events occurring at different *** average stress is 25.68 MPa,with the strain rates(έ)ranging from 9.77×10^(−14)s^(−1)to 6.52×10^(−16)s^(−1).The finite strain of the Guoxuepu ductile shear zone indicates an elongated strain *** average kinematic vorticity of the Guoxuepu ductile shear zone is 0.88,implying that the shear zone is dominated by simple *** muscovite selected from the protomylonite samples in the Guoxuepu ductile shear zone yields a 40Ar-39Ar age of 60.09±0.38 *** is suggested that,coeval with the initial Indo–Eurasian collision,the development of strike-slip faults led to a weak and unstable crust,upwelling of lower crust magma,then induced the detachment of the Jitang metamorphic complex in the Eocene.

关键词： ^(40)Ar/^(39)Ar dating strain pattern vorticity EBSD Guoxuepu shear zone Jitang metamorphic complex

Middle Devonian ostracods from Jiwozhai patch reef(Dushan,Guizhou Province,South china):Biostratigraphic and palaeoecological implication

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Journal of Palaeogeography 2024年第3期13卷 581-593页

作者： Jun-Jun Song Jia-Yuan Huang Wen Guo Kun Liang Yu-Cong Sun Zhi-Hong Wang Wen-Kun Qie State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina Hubei Key Laboratory of Paleontology and geological Environment Evolution Wuhan Center of China Geological SurveyWuhan 430205Hubei ProvinceChina University of Chinese Academy of Sciences NanjingNanjing 211135Jiangsu ProvinceChina

The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South china were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South china and Laurentia-Baltica during the Middle Devonian.

关键词： Ostracods Givetian Jiwozhai patch reef Dushan Palaeoecology

Pan-African metamorphism and magmatism in the Prydz Belt,East Antarctica:a geochronological perspective

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Advances in Polar Science 2024年第2期35卷 143-156页

作者： BAO Hong WANG Wei-(RZ) LIU Xinshu ZHAO Yue GONG Tingnan LIU Xiaochun CUI Ying TIAN Zuolin Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural ResourcesBeijing 100081China china University of Geosciences(Beijing) Beijing 100081China MOE Key Laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The Prydz Belt in East Antarctica underwent extensive reworking during the late Neoprotertozoic–early Paleozoic Pan-African orogeny,which is characterized by granulite facies,clockwise P–T paths,and high dT/dP *** study compiles the existing age and composition data of zircon and monazite from metamorphic rocks and links their key characteristics to the metamorphic evolution of the Prydz *** frequency of zircon U–Pb ages starts to increase noticeably from~555 Ma,peaking between 530 Ma and 520 Ma,followed by a dramatic decline after 520 *** Th/U values(>0.1)of zircon are observed from~545 Ma,displaying a noticeable increasing trend in Th/U values before a rapid decline from~520 *** frequency of monazite ages progressively increases from~540 Ma,reaching its peak at 515 Ma,and then rapidly decreases after 490 *** with the crystallization behaviors of zircon and monazite,this study suggests that the systematic changes in Th/U values of zircon after 545 Ma indicate a transition in the thermal regime of the Prydz Belt towards the cooling *** growth of zircon and monazite corresponds to the post-peak cooling process,while the crystallization peak of monazite lags behind that of zircon by~5–15 Ma,which indicates a relatively low cooling *** the granitic intrusions accompanied the entire metamorphic evolution,the majority of them are younger than 520 *** results suggest that the Pan-African event likely peaked at~555–545 Ma and gradually cooled to near-solidus conditions at~520–510 Ma,with a relatively slow average cooling process.

关键词： East Antarctica Prydz Belt Pan-African orogeny zircon monazite U–Pb dating

Responses of Nutrients to the Precipitation Variation and Land Use in Subtropical Monsoonal Small Mountainous Rivers:A Case Study of Baixi Watershed

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Journal of Ocean University of china 2024年第2期23卷 383-391页

作者： TIAN Yuan GAO Fei CAO Ke LV Shenghua DUAN Xiaoyong YIN Ping Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266237China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China

Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and *** order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry *** concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),*** by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle *** rainstorms during the Meiyu period in the watershed caused the pulse runoff in the *** maximum daily runoff reached 70 times that before *** maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,*** view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.

关键词： small mountainous river uneven precipitation rainstorm pulse runoff nitrogen and phosphorus

Evaluation of the Shallow Gas Hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method

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Journal of Ocean University of china 2024年第1期23卷 119-128页

作者： CHEN Qiang WAN Yizhao WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei Key Laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao 266071China Laboratory for Marine Mineral Resources Laoshan LaboratoryQingdao 266071China CNPC Offshore Engineering Company Limited Beijing 100028China Technology Innovation Center for Marine Methane Monitoring Ministry of Natural ResourcesQingdao 266071China

It has been evidenced that shallow gas hydrate resources are abundant in deep oceans *** geological back-ground,occurrence,and other characteristics differ significantly from deep-seated *** of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production *** a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling ***-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas *** information collected from an investigation site close to the offshore production well in the South china Sea is used to assess the essential components of this plan,including well construction stability and gas production *** demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid ***,the traditional well structure is unstable,and the suction anchor is advised for better mechanical *** gas produc-tion rate can be significantly increased by combining hot water injection and depressurization ***,the suitable produc-tion equipment already in use is discussed.

关键词： shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation