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Progress and review of the studies on the end-Triassic mass extinction event

Science china Earth sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2. LU Yuanzheng1,2.3 & XU Daoyi4 1. Research institute of Petroleum Exploration and Development, Beijing 100083, china 2. {2. laboratory of Oil and gas Reservoir of Petrochina, Beijing 100083, china 3. china University of Geosciences, Beijing 100083, china 4. institute of geology, china Earthquake Administration, Beijing 10002., china 1. Research institute of Petroleum Exploration and Development 100083 Beijing China 2. key laboratory of Oil and {2. Reservoir of Petrochina 100083 Beijing China 3. china University of Geosciences 100083 Beijing China 4. institute of geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3 & DENG Jun1 1 State key laboratory of Geological Processes and Mineral Resources,{2. University of Geosciences,Beijing100083,{2. 2.laboratory of Nuclear Analysis Techniques,institute of High Energy Physics,chinese academy of sciences,Beijing 100039,{2. 3 Department of geology,Peking University,Beijing 100871,{2. 1. State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―350℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132.Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

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Characterization of MASDs of surface soils in north china and its influence on estimating dust emission

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chinese Science Bulletin 2004年第20期49卷 2169-2176页

作者： MEI Fanmin1,2. ZHANG Xiaoye1, LU Huayu1, SHEN Zhenxing1 & WANG Yaqiang1 1. State key laboratory of Loess and Quaternary {2., institute of Earth Environment, chinese academy of sciences, Xian 710075, china 2. Xian University of Engineering Science and Technology, Xian 710048, china State key laboratory of Loess and Quaternary {2. Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Xi''an University of Engineering Science and Technology Xi''an 710048 China

The micro-aggregated size distribution (MASD) of surface soil is an important parameter for modelling dust emission. However, there is no dataset of MASDs of all sur-face soil types in north china. The MASDs are here pre-sented, measured by dry sieving, for typical surface soil sam-ples, including sandy soil, gravelly sand soil, gravelly loam soil, loam soil and silt loam soil, collected from sandy deserts, Gobi deserts, oases, farmlands in steppe regions and steppe areas in north china. The MASDs of various surface soil types exhibit a combination of several log-normal distribu-tions of five separated sizes with mean mass median diame-ters (MMDs) of 90, 2.0, 390, 600 and 980 mm, respectively, and mean standard deviations (SDs) of 1.2., 1.40, 1.2., 1.35 and 1.2. respectively. The log-normal distributions corre-spond to very fine sand, fine sand, medium sand, coarse sand and very coarse sand population. On the basis of characteri-zation of the retrieved MASDs of various surface soil types in north china, dust emission fluxes are modelled by a dust production model (DPM model). It is shown that dust emis-sion has been significantly influenced by MASDs. Fine sand and very fine sand are always associated with the highest dust emission fluxes. Emission fluxes of the medium sand, gravelly sand soil, gravelly loam soil and loam soil are lower than those of very fine sand and fine sand, but larger than those of the coarse sand. The differences in dust emission fluxes vary among the different soil types from 101 to 103 mg·m-2.s-1. Dust emission fluxes from sandy deserts and farmlands covered with sand sheets in north china rang from 101 to 104 mg·m-2.s-1 while those from Gobi deserts, farmlands and steppes with gravelly desertification range from 101 to 102.mg·m-2. s-1. The modelled results indicate that deserts and farmlands with sand are the major dust sources in north china.

关键词：华北地区 MASDs 微块状粒度分布地面土壤粉尘排放壤土大气污染气溶胶

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Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2.FANG Xiaomin 1,2.GAO Junping1, NIE Junsheng1,YAN Maodu1,3,XU Xianhai1 & SUN Dong1 1. MOE National laboratory of Western china抯 Environmental Systems & College of Resource and Environment,{2. University,{2. 730000,china 2. State key laboratory of Loess and Quaternary geology ,institute of Earth Environment,chinese academy of {12.,Xi抋n 710075, china 3. Department of Geological {12.,University of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National laboratory of Western china\'s Environmental Systems & College of Resource and Environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3An *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.2.,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the chinese elephant Anancus sinensis are firstly constrained at about 5.2. MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

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The history of crustal uplift and metamorphic evolution of Panzhihua-Xichang micro-palaeoland, SW china:Constraints on Sm-Nd, ^(40)Ar/^(39)Ar and FT ages of granulites

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Science china Earth sciences 2004年第8期47卷 689-703页

作者： XU Shijin1, LIU Wenzhong1, WANG Rucheng1, YU Hangbo1, LI Daming2. WAN Jinglin2.& FANG Zhong1 1. Department of Earth sciences and State key {2. for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, china 2. institute of geology, china Seismological Bureau, Beijing 10002., china 1. Department of Earth sciences and State key {2. for Mineral Deposits Research Nanjing University 210093 Nanjing China 2. institute of geology China Seismological Bureau 100029 Beijing China

Panzhihua-Xichang (Panxi) micro-palaeoland is the oldest terrane on the western margin of the Yangtze Block. Some intermediate-basic granulites are considered to be the crys-talline basement of lower crust in the terrane. Granulite-facies metamorphism of the granulites was developed in the period from 1186 Ma to 112. Ma. The origin of granulites was related to the collision orogenic process occurring when the micro-palaeolands merged to form the Rodinia Supercontinent. Amphibolite-facies retrogressive metamorphism of granulites took place in the period from 877 Ma to 82. Ma. This period was consistent with the breakup time of the Rodinia Supercontinent. 40Ar/39Ar ages and fission track (FT) ages of granulites in the Panxi mi-cro-palaeoland show that the vertical movement history of crustal rocks was a slow uplift process of the rigid terrane in the time from Neoproterozoic to Mesozoic. The subduction of India Plate towards Euroasia Plate resulted in the rapid uplift of the Qinghai-Tibetan Block in Cenozoic. Meanwhile, the Qinghai-Tibetan Block moved towards east. Consequently the Panxi terrane was uplifted rapidly. As a result of the collision orogeny between the Qinghai-Tibetan Block and the Panxi terrane, the granulite-facies crystalline basement in this region was exhumed and exposed to the surface.

关键词： granulite,isotope geochronology,crustal uplift movement,Panzhihua-Xichang region,western margin of Yangtze Block.

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Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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Science china Earth sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2.LIN XueHui1,2.YAO De3,4 & GUO WeiDong5 1 key laboratory of Marine Oil and {2. Resources and Marine Environment,Ministry of Land and Resources,Qingdao 2.6071,china 2.Qingdao institute of Marine geology,china Geological Survey,Qingdao 2.6071,china 3 institute of Resources and Environment,Shandong University of Technology,Zibo 2.5049,china 4 institute of Oceanology,chinese {12. of sciences,Qingdao 2.6071,china 5 Department of Oceanography,Xiamen University,Xiamen 361005,china 1. key laboratory of Marine Oil and {2. Resources and Marine Environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2.combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

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INTRODUCTION TO FOSSIL ALGAE AND STROMATOLITES

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微体古生物学报 2003年第1期 2-4页

作者： MU Xinan 1,2. YUAN Xunlai 1 1 Nanjing institute of geology and Palaeontology,{2., Nanjing 2.00082.State key laboratory of Palaeobiology and Stratigraphy, Nanjing 2.0008

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Serpentinization of peridotites from the southern Mariana forearc

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Progress in Natural Science:Materials International 2009年第10期19卷 1287-1295页

作者： Xiaomei Wang a,b,Zhigang Zenga,Junbing Chenc a key laboratory of Marine {2. and Environment,institute of Oceanology,chinese academy of sciences,7 Nanhai Road,Qingdao 2.6071,china b Graduate School of chinese academy of sciences,19 Yuquan Road,Beijing 100049,china c Geological Brigade of Hydro{2. and Engineering {2.,Zhejiang Geological Prospecting Bureau,2.6 Baoshan Road,Ningbo 315012.china [a]key laboratory of Marine {2. and Environment Institute of Oceanology Chinese Academy of Sciences 7 Nanhai Road Qingdao 266071 China [b]Graduate School of chinese academy of sciences 19 Yuquan Road Beijing 100049 China [c]Geological Brigade of Hydrogeology and Engineering geology Zhejiang Geological Prospecting Bureau 206 Baoshan Road Ningbo 315012 China

A detailed petrologic and mineralogic study was carried out on serpentinized peridotites dredged from the southern landward slopes of the Mariana Trench,in order to reveal the serpentinization process of these unusual rocks and to identify the sole presence of the mineral *** constituent minerals of these southern Mariana forearc peridotites are olivine,amphibole and spinel,as well as serpentine,chlorite and *** with serpentinite seamounts,the serpentinized peridotites from the southern Mariana forearc are characterized by the absence of magnetite and brucite,and the common presence of talc;besides,the serpentine mineral variety is simplex,only *** mineral chemistry and mineral phase relationships,we conclude that(1) the absence of magnetite in the serpentinized peridotites is due to incomplete serpentinization,other than magnetite,the iron end-member in olivine forms Ferich brucite and Fe-rich serpentine;(2. brucite is not stable with high silica activity,reacting with later SiO2.rich fluid and then forming lizardite,leading to a lack of brucite in these serpentinized peridotites;(3) the occurrence of talc is the result of later SiO2.rich fluid reactions with lizardite;and(4) the reason for the sole occurrence of lizardite is that the temperature condition of our study are awas nothig henough for the formation of antigorite(whichisstable at >500 °C).Despite the broad overlap of lizardite and chrysotile in growth temperature,differences in the modes of occurrence of lizardite and chrysotile,such as the scarcity of H2.,low porosity and permeability,as well as the actual situation of initial serpentinization in the study area,result in the absolute prevalence of lizardite over chrysotile in the area.

关键词： Peridotite Serpentinization Mineral chemistry Lizardite Mariana

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Dating of the Karakorum Strike-slip Fault

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Acta Geologica Sinica(English Edition) 2001年第1期75卷 10-18页

作者： ZHOU Yong, XU Ronghua, YAN Yuehua, PAN Yusheng,Tsanyao Frank YANG, Wei LO and WU Chunming laboratory of Lithosphere Tectonic Evolution, institute of geology and geophysics,{2., Beijing 10002.Department of geology, National Taiwan University, 2.5 Choushan Road, Taipei 106-17, TaiwanDepartment of geology, chinese Culture University, Hwa-kang, Yang-Ming-Shan, Taipei, Taiwan institute of geology, chinese academy of Geological sciences, Beijing 100037 laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 Department of geology National Taiwan University 245 Choushan Road Taipei 106–17 Taiwan Department of geology Chinese Culture University Hwa-kang Yang-Ming-Shan Taipei Taiwan institute of geology Chinese Academy of Geological Sciences Beijing 100037 [?]5Zhou Yong Male born in 1968 graduated from Chengdu College of geology with a master's degree in 1991. From 1991 to 1995 he focused on ore deposit investigation. Since 1995 he has studied structural geology associated with the Qinghai-Tibet plateau. Tel: (010) 62008438.

This paper mainly discusses the timing of the Karakorum strike-slip fault, and gives a brief introduction of its structures, offset, and deformational style. This fault strikes NNW-SSE. Asymmetrical folds, stretching lineation, S-C fabrics, feldspar and quartz s?-porphyroclasts, domino structure, shear cleavages and faults in the fault zone are products of tectonic movements. They all indicate a dextral slip sense of faulting. Mylonitic bands are widely developed along this fault. Phengite appears, indicating rather high deformational pressure. Geochronological data indicate that the Karakorum strike-slip faulting occurred from 6.88±0.36 to 8.75±0.2. Ma. The cumulative displacement from Muztag Ata to Muji is about 135 km.

关键词： Karakorum fault kinematics timing displacement

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Youger Dryas and Heinrich events recorded by magnetic susceptibility of sediments from the central temperature area of Western Pacific Warm Pool

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chinese Science Bulletin 2003年第8期48卷 808-813页

作者： TANG Xianzan, CHEN Zhong,YAN Wen & CHEN Muhong The Open laboratory of geology and Paleoenvironment of Marginal Sea, South{2. Sea institute of Oceanology, chinese academy of sciences, Guangzhou 510301,{2. The Open laboratory of geology and Paleoenvironment of Marginal Sea South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Three short geomagnetic excursions, the Go thenburg, Mono Lake and Mungo (or Maelifell) in the Brunhes Positive Polarity period, were revealed based on the studies of magnetostratigraphy, susceptibility (c) and d 18O of sediments in core WP 92.5 from the central temperature area of the Western Pacific Warm Pool (WPWP), and the ages of them are 12.111.3 kaBP, 2..02..0 kaBP, and 31.02..0 kaBP respectively. Furthermore, the Younger Dryas (YD) and Heinrich (H) cold events were also discov- ered in this core by the susceptibility record. The YD cold event occurred at the depth of 302. cm with an age of 11.510.6 kaBP; H1, H2.and H3 cold events occurred at depths of 5139 cm, 10891 cm and 14012. cm with ages of 15.113.0 kaBP, 2..02..1 kaBP and 30.62..2.kaBP respectively, which well correspond to the H1, H2. H3 events recorded by susceptibility of core SU90-09 from middle At- lantic, indicating that the susceptibility change of marine sediments can be an important sign of climatic frequent fluc- tuations.

关键词：磁化率沉积物西太平洋磁性地层学

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