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Sorption behavior of U(VI), ^(234.U(VI) and ^(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china.Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, luo Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. Department of Earth sciences, State Key Laboratory of Mineral Deposit Research, nanjing University, nanjing 210093, china.2. Center of Materials Analysis, nanjing University, nanjing 210093, china.3. Department of Environmental Science and Engineering, nanjing University, nanjing 210093, china.4. Beijing geology institute, Nuclear Industry, Beijing 100029, {14. Department of Earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis nanjing University nanjing china Department of Environmental Science and Engineering nanjing University nanjing china Beijing geology institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 234.(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china.are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Jurassic integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science china.Earth sciences 2024年第4期67卷 1195-1228页

作者： Jianguo LI Xin RAO Lin MU Xiaohui CUI Xin LI hui luo Peixue LIU Center for Excellence in Life and Paleoenvironment Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China nanjing College University of Chinese Academy of SciencesNanjing 211135China

The Qinghai-Tibetan Plateau experienced a unique geological evolution during the Jurassic,driven by the termination of the Palaeotethys and the reduction of the *** Indian Plate separated from the northern margin of Gondwana and drifted northward from the Southern *** that the timing of strata serves as the basis for reconstructing geological history,the present work aimed to develop a new multiple stratigraphic and chronologic framework for the Jurassic strata of the Qinghai-Tibetan Plateau region via a synthesis of the material on lithostratigraphy,palaeontology,iso-radiometric dating,magnetostratigraphy,and other techniques with an emphasis on recent progress and *** new framework included the Jurassic System from the four major subdivisions of the plateau:the Baryan Har,Qiangtang,Lhasa-Gandise,and Southern Xizang(Himalaya).Ultimately,a more complete,refined biostratigraphic sequence was proposed,comprising the most common fossils in the plateau and those that are stratigraphically significant for the Jurassic stratigraphy,including ammonites,bivalves,brachiopods,foraminifera,radiolarians,and dinoflagellate cysts for the marine strata,and pollen and spores,and charophytes for the terrestrial *** biostratigraphic framework was correlated with the Jurassic international standard zonation of the Geological Time Scale 2020 via standard or representative species or genera of *** on this framework,we constructed a lateral correlation of the Jurassic strata between different basins of the *** palaeontologic correlation in the present work shows that the Lhasa-Gandise Block had a closer relationship with the Qiangtang Block than with the Southern Xizang Himalaya during the Jurassic ***,the Lhasa-Gandise Block and Qiangtang Block shared similar marine fauna features of the north marginal East *** contrasts the opinion suggesting that the Yarlung Zangbo Tethys was a small back-arc basin.A c

关键词： Biostratigraphy Chronostratigraphy Correlation Yarlung Zangbo suture Bangong Co-Nujiang suture Tethys

Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South china

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 150-167页

作者： FANG Chaogang ZHANG Chengcheng MENG Guixi xu Jinlong xu Naicen LI Hualing LIU Mu LIU bo institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China nanjing Center China Geological SurveyNanjing 210016China Exploration Research institute Anhui Provincial Bureau of Coal GeologyHefei 230088China china.United Coalbed Methane Corporation Ltd. Beijing 100015China Geological Survey of Anhui Province Hefei 230001China Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source ***,the mechanism of organic matter(OM)enrichment throughout this period is still *** on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM *** Phases are distinguished based on the TOC and environmental *** Phase I,anoxic conditions driven by water restriction enhanced OM *** Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM *** Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation *** IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic *** Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary *** I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions.

关键词： geochemistry redox condition primary productivity OM accumulation Lopingian/Changhsingian Lower Yangtze region

Geochemical Forms of Phosphorus in Sediments of Three Large, Shallow Lakes of china

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Pedosphere 2006年第6期16卷 726-734页

作者： ZHU Guang-Wei QIN bo-Qiang ZHANG Lu luo Lian-Cong nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

A sequential extraction method for the fractionation of phosphorus （P） in lake sediments was used to analyze phos- phorus fractions of sediments taken from three large, shallow. eutrophic freshwater lakes of china.Talhu Lake. Chaohu Lake, and *** Lake. All three lakes are located in the lower reaches of the Changjiang River （Yangtze River）. In Taihu Lake and Chaohu Lake, algae blooms occurred every year, while Longgan Lake was a macrophyte-dominated lake. Results showed that exchangeable phosphorus fractions were much higher in the eutrophic lake sediments than in the macrophyte-flourishing lake sediment. Also, the ratio of Fe：P in the sediments of the algae-predomlnant lakes was generally much lower than that in the macrophyte-predominant lakes. Thus, the geochemical fractions of phosphorus in sediments had a closer relationship with the type of aquatic vegetation.

关键词： algal bloom macrophyte phosphorus sediment shallow lakes

Characteristics of Paleontological Communities in Surface Sediments of the Southern South china.Sea and Their Paleoclimatic and Paleoenvironmental Significance

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Journal of Earth Science 2024年第1期35卷 144-154页

作者： Jing Zhao Li Zhang Xiaoyan Wang Jinglian Ge Min xu Wei Chen Mao luo Qianyong Liang Qiuhua Yu Shuaibing luo Wenkun Qie Key Laboratory of Marine Mineral Resoures Ministry of Natural ResourcesGuangzhou Marine Geological SurveyChina Geological SurveyGuangzhou 511458China National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Understanding the spatial and temporal distribution of different paleontological communities in the southern South china.Sea(SCS)is fundamental to explore its paleoclimatic and paleoenvironmental *** this study,foraminifera,pollen and diatoms from 100 surface sediment samples covering 4.000 km^(2) of sea floor in the southern SCS were comprehensively investigated in terms of their assemblage and *** results showed the existence of abundant foraminifera and pollen in most of the samples,although diatom communities were relatively *** were dominated by ***,***,***,while diatoms were characterized by ***,*** and ***,indicating a typical tropical marine *** pollen assemblages showed a better reflection of montane rainforest,tropical rainforest and *** spatial differences among foraminifera assemblages may indicate the effect of water depth and a warmer environment in the southeast part of the study area,while the spatial patterns of diatom and pollen assemblages imply the influence of coastal *** study also noted that the compositions of paleontological communities in the SCS can vary significantly in a short distance,and synthesized studies on multiple biological groups are needed to reconstruct the Quaternary climate and the oceanographic environment.

关键词： southern South china.Sea sediments foraminifera diatom pollen

THE UNIQUE GENUS PALAEONTINODES (INSECTA, HEMIPTERA,PALAEONTINIDAE) FROM DAOHUGOU AND ADJACENT REGION:SYSTEMATICS, INDIVIDUAL ABERRATION AND TAPHONOMY

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THE UNIQUE GENUS PALAEONTINODES (INSECTA, HEMIPTERA,PALAEONT...

Permian integrative stratigraphy,biotas,paleogeographical and paleoclimatic evolution of the Qinghai-Tibetan Plateau and its surrounding areas

第二届国际古生物学大会

作者： bo WANG, Haichun ZHANG, Yan FANG State Key Laboratory of Palaeobiology and Stratigraphy, nanjing institute of {4. and palaeontology, chinese academy of sciences, nanjing 210008, china.

The extinct family Palaeontinidae comprises more than thirty genera. However, none of them was erected on the basis of both a complete forewing and hindwing. Very recently, more than three hundred palaeontinid specimens have been discovered from Daohugou and adjacent regions. About half of them are attributed to Palaeontinodes, comprising five new species. Strange-

关键词： Palaeontinidae individual aberration convergence taphonomy

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Science china.Earth sciences 2024年第4期67卷 1107-1151页

作者： Shuzhong SHEN Yichun ZHANG Dongxun YUAN Haipeng xu Qi JU Hua ZHANG Quanfeng ZHENG Mao luo Zhangshuai HOU State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of chinese academy of sciences Nanjing 210049China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China

The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical *** supercontinent Pangea was formed to its maximum during this interval,hampering a global east-to-west trending equatorial warm ocean ***,a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea,and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic *** and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan *** distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics,reflecting these blocks’different paleolatitude settings and drifting *** Himalaya Tethys Zone south to the Yarlung Zangbo suture zone,located in the northern Gondwanan margin,yields fossil assemblages characterized by cold-water organisms throughout the Permian,and was affliated to those of the *** of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian(Middle Permian)to Early Triassic in *** exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions,suggesting that they most probably represent seamount deposits in the Neo-Tethys *** the Asselian to Sakmarian(Cisuralian,also Early Permian),the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian,and contained typical Gondwana-type cold-water *** the middle Cisuralian(~290-280 Ma),the Cimmerian microcontinents rifted off from the Gondwanaland,and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian *** slices of micro

关键词： Permian Tethys Ocean Qinghai-Tibetan Plateau Biotas Paleogeography

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and luo Xinrong (Postgraduate School of Guizhou University, Guiyang 550025, china.nanjing institute of {4. and Mineral Resources, nanjing 210016, china.Geological Survey of No. 3 Geological Party, Xinjiang, Kurle 84.000, china. [a]Postgraduate School of Guizhou University Guiyang China [b]nanjing institute of geology and Mineral Resources Nanjing China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3-1. 4.mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

Devonian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science china.Earth sciences 2024年第4期67卷 1036-1070页

作者： Wenkun QIE Kun LIANG Wen GUO Biao GAO Junjun SONG bo CHEN Pu HUANG Li QIAO Honghe xu Jitao CHEN Yucong SUN Yichun ZHANG State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of chinese academy of sciences Nanjing 211135China

The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in *** records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern ***,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical *** blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning *** two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana *** on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of *** results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South china.Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South china.and Australian *** the Emsian(Early Devonian),the South china.Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaosh

关键词： Devonian Paleo-Tethys Ocean Integrative stratigraphy Biotas Provenance Analysis Paleogeography