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Science china Earth {1. 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2.& SU Li3 1 institute of geology, Chinese Academy of {2. sciences, beijing 100037, china 2.College of Earth sciences, Jilin University, Changchun 130061, china 3 The {2. Laboratory Center and State Key Laboratory of {2. Processes and Mineral Resources, china University of Geo- sciences, {12. 100083, china 1. institute of {1. Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 1.6Hf/1.7Hf ratios range from 0.2.2.1. to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2. Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research, Department of Earth sciences, Nanjing University, Nanjing 2.0093, china 2. Tarim Oilfield Company Exploration & Development Research {2., Ku’erle 841000, china 3. {2. of Mineral Resources, Chinese Academy of geological sciences, beijing 100037, china) State Key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China arim Oilfield Company Exploration & Development Research institute Ku’erle 841000 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-{1.). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 1..8‰ and 1..0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (1..9‰—1..9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures ({1..4—{1..3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china Earth {1. 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2. XIONG Shangfa3 & HUANG Fengbao1 1. Nanjing institute of geology and Paleontology,Chinese Academy of {2.,Nanjing 2.0008,china 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. institute of geology and Geophysics,Chinese Academy of {2.,beijing 10002.,china Nanjing institute of {1. and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of {1. and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium Chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 1.000 and 872. a BP, the Aneurolepidium Chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 872. to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

Metallogenic characteristics of epithermal gold deposits in china

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Chinese Science Bulletin 1999年第S2期44卷 136-138页

作者： FENG Jianzhong~1.and WANG Jingbin~2.1. Department of {1., Peking University, beijing 1.0871.{2. 2. beijing institute of {1. For Mineral Resources, beijing 1.001.0}{2. Department of geology Peking University Beijing 100871 China beijing {1. of {2. for Mineral Resources Beijing 100012 China

VOLCANIC-SUBVOLCANIC rocks are extensively distributed in china, in which a series of epithermal golddeposits related to volcanism have been discovered. 1.Metallogenic tectonic settings of epithermal gold deposits The epithermal gold deposits are mainly formed under the following tectonic settings: (i) ancient island arc collision, such as Xingxingxia island arc, Armantai island arc, Beishan island arc and Jueluotage island arc, etc. in periphery of Gunggar, Altai, Baishan, etc. in ancient Europe domain; (ii) extension area of continental margin of back arc, such as Fujian, Zhejiang, Jiangsu and Henlongjiang, *** circum-Pacific metallogenic domain; (iii) Mesozoic-Cenozoic island arc, such as the Tethys-Himalayametallogenic domain and Taiwan; (iV) intracontinental faulting depression or intraplate deep-seatedfaults, such as northern Hebei, Liaoning, Inner Mongolia at the north margin of the North china platformand periphery of Taicheng-Loujiang fault.

关键词： metallogenic characteristics gold deposits china.

Lithosphere types in North china:Evidence from {1. and geophysics

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Science china Earth {1. 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. institute of geology, Chinese Academy of {2. sciences, beijing 100037, china 2. Development and Research Center, china {2. Survey, beijing 100037, china 3. china University of Geosciences, {12. 100083, china 4. china University of Geosciences, Wuhan 430074, china 5. Information Center of Ministry of Land and Resources, {12. 100812. china 6. institute of geology, State Seismological Bureau, {12. 10002., china 1. institute of {1. Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of Geo{1. 100083 Beijing China 4. china University of Geo{1. 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. institute of {1. State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North{1., three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North{1. platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North{1. Platform is a remnant of cratonic lithosphere after the North{1. platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North{1. craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North{1. platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North{1. in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

High-temperature phases of pyrophyllite and their evolutionary characteristics

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Chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, Chinese Academy of {1., Changsha 41.01.,{2. 2. institute of geology, Chinese Academy of {1., beijing 1.002.,{2. Changsha institute of Ceotectonics Chinese Academy of Sciences Changsha China institute of {1. Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1.50℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1.1.℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

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

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Science china Earth {1. 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,{2. 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, beijing 100083,{2. 3.{2. University of Geosciences, beijing 100083,{2. 4. institute of geology,{2. Earthquake Administration, beijing 10002.,{2. 1. Research institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petro{1. 100083 Beijing China 3. china University of Geo{1. 100083 Beijing China 4. institute of {1. 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.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth {1. 2006年第1期49卷 77-87页

作者： MA Jinlong1.2. TAO Mingxin2.3 & YE Xianren2.1. Resources and Environmental School, Lanzhou University, Lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, institute of {2. and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china 3. College of Resources Science & Technology, beijing Normal University, beijing 1.0875, china 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of Resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_{1. CO and H_{1. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.8{1.Ra to {1.74 Ra, whereas^(40)Ar/^(36)Ar from {1.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from {1..6 x 1.~9 to 1.50 x 1.~9,N_{1.Ar from 9{1. to 5661.1. and N_{1.~3He from {1.5 x 1.~9 to {1. x 1.~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Oxygen isotope compositions of eclogites in Rongcheng,Eastern china

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Chinese Science Bulletin 2003年第4期48卷 372-378页

作者： CHU Xuelei1.2. GUO Jinghui1.2. FAN Hongrui1.2.& JIN Chengwei1.1. institute of geology and Geophysics, Chinese Academy of {2., beijing 1.002., china 2. Key Laboratory for Mineral Resources Research, Chinese Academy of {2., beijing 1.01.1. china Correspondence should be addressed to Chu Xuelei institute of {1. and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory for Mineral Resources Research Chinese Academy of Sciences Beijing 100101 China

Collected from the Rongcheng region, Shan-dong Province, the three types of eclogites suffering the UHP (i.e. ultra-high pressure) metamorphism have obviously dif-ferent oxygen isotope compositions. The eclogites occurring in regional orthogneisses and ultramafic rocks have the oxy-gen isotope compositions of normal eclogites in the world,but the eclogites existing in marbles are extremely enrichedin 1.O. By applying oxygen isotope geothermometry, for theall types of eclogites, the temperature estimates of quartz-garnet pair, in principle, indicate the formation temperatures of eclogites, so that the peak-metamorphic temperatures are estimated to be averagely little higher than 800℃, which are consistent with the estimates by using other geothermome-ters according to cation partitioning between coexistingphases. The d 1.O values of eclogitic inclusions hosted inmarbles from Yangguantun, Rongcheng region, are farhigher than the values of eclogites (including eclogitic inclu-sions in marbles) from the Dabieshan and other places of the Sulu. The oxygen isotope compositions of various mineralsindicate that the formation temperatures of eclogites fromthe Rongcheng region, in general, are higher than that from the Dabieshan and the southwestern part of the Sulu, but the dispersive temperatures estimated by different mineral pairs probably reflect that the UHP eclogites from the Rongcheng region generally suffered overprinted metamorphisms dur-ing the exhumation.

关键词：苏鲁超高压变质带 UHP 山东荣成榴辉岩氧同位素成分

Effect and mechanism of stresses on rock permeability at different scales

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Science china Earth {1. 2006年第7期49卷 714-723页

作者： YIN Shangxian1.& WANG Shangxu2.1. Safety Engineering College, North{1. institute of Science and Technology, Yanjiao, {2. 1.1.01.{1. 2. Key Laboratory of Geophysics Exploration,{1. University of Petroleum, {2. 1.0083,{1. 1. Safety Engineering College North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of Geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1. At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2. At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.