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REE Geochemistry and Mineralization Characteristics of the Zudong and Gnanxi Granites, Jiangxi Province

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 139-157页

作者： Huang Dianhao, Wu Chengyu institute of Mineral Deposits, chinese academy of geological sciences, {2. and Han Jiuzhu Southern Jiangxi geological Survey Party, Jiangxi Bureau of geology and Mineral Resources, Ganzhou Zhang Zhong min institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

The Zudong and Guanxi granites are original rocks of the ion adsorption-type HREE and LREE deposits in weathering crust of granites. The ΣREE value and LREE/HREE ratio of the Zudong granite are 2.4 ppm and 0.81-0.2. respectively, and the average Y/ΣREE ratio is 35.8-54.5%. This is mainly due to magmatic crystallization and evolution and deuteric metasomatism (albitization, muscovitization and fluorite-doveritization). These alterations resulted in endogenic mineralizations of yttrium-group REE fluorine carbonates, silicates and arsenates. The Guanxi granite is characterized by LREE enrichment (the average LREE/HREE ratio is 2.43).

关键词： REE Geochemistry and Mineralization Characteristics of the Zudong and Gnanxi Granites Jiangxi Province

Virtual ChuanDian--A parallel numerical modeling of Sichuan-Yunnan regional strong earthquake activities: Model construction and parallel simulation

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Science china Earth sciences 2009年第10期52卷 1585-1598页

作者： ZHANG Huai1, WU ZhongLiang1,2. ZHANG DongNing2. LIU Jie2. WANG Hui2. YAN ZhenZhen1,2.& SHI YaoLin11 Laboratory of Computational Geodynamics, Graduate University of chinese academy of {2., beijing 100049, china 2.institute of Geophysics, chinese Earthquake Administration, beijing 100081, china 1. Laboratory of Computational Geodynamics Graduate University of Chinese Academy of Sciences Beijing 100049 China 2. institute of Geophysics Chinese Earthquake Administration Beijing 100081 China

Reasonable use of mathematical modeling and numerical simulation of regional earthquake activities has attracted more and more attentions in realistic seismicity studies in recent years. The inherent nature of their attendant multi-scale properties, from either the temporal or the spatial direction, necessitates the use of the cutting-edge massive parallel data processing techniques. Our study here is focused on the model construction and numerical simulation of the regional stress evolution after large earthquake sequences along the fault zones in Sichuan and Yunnan areas, using large-scale parallel finite element approximations with tens of millions of unstructured meshes on the distributed systems. The objective of our study is to provide a state-of-the-art model and a large-scale numerical simulation platform, on which estimation of the risk of large earthquake triggering sequences can be carried out in a middle or long-term time scale with realistic data and constrains inputted from field observation and geological survey.

关键词： Sichuan-Yunan area seismic processing parallel simulation initial stress field

shrimp dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet

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chinese Science Bulletin 2007年第7期52卷 936-941页

作者： SHI RenDeng1,2.1 School of Earth and Space sciences, University of Science and Technology of china, Hefei 2.002., china 2.institute of geology, chinese academy of geological sciences, beijing 10003., china (email: shird@***) School of Earth and Space sciences University of Science and Technology ofChina Hefei 230026 China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The shrimp U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12. MSWD = 1.2., suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 SSZ型蛇绿岩 shrimp 测年

Discovery of eclogite and its geological significance in Qiangtang area, central Tibet

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Science Bulletin 2006年第9期51卷 1095-1100页

作者： LI Cai1, ZHAI Qingguo2. DONG Yongsheng1 & HUANG Xiaopeng11. College of Earth sciences, Jilin University, Changchun 130061, china {2., chinese academy of geological sciences, Bei- jing 10003., china College of Earth sciences Jilin University Changchun 130061 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 40Ar/39Ar age of 2.0 Ma and a phengite 40Ar/39Ar age of 2.1.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- chinese epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.

关键词： Qianghai-Tibet Plateau Qiangtang eclogite tectonics.

Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 466-479页

作者： Geng Yuansheng, Liu Dunyi and Song Biaoinstitute of geology,{2., 2. Baiwanzhuang,beijing 10003., china institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 China [?]Geng Yuansheng Born in January 1950 got a master degree at the Changchun College of geology in 1981 long engaged in the study of Early Precambrian geology and metamorphic petrology now research professor at the institute of geology Chinese Academy of Geological Sciences.

Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2.68-2.32.Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2.61 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2.50 Ma, resulting in crustal thickening. The thickening was enhanced at 2.61-2.03 Ma by the widespread intrusions of granodioritic magma. In the period of 2.77-2.61 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 2.00 Ma ago, and finally pink granite intrusions at 2.44-2.87 Ma resulted in the formation of a granite zone.

关键词： geological event Early Precambrian geochronology granulite northwestern Hebei

Primary Study on Quantitative Reconstruction of Middle-Late Eocene Climate in Jianghan Basin

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Journal of china University of Geosciences 2002年第3期13卷 252-259页

作者： Tong Guobang Liu Zhiming institute of Hydrogeology and Environmental geology, chinese academy of geological sciences, Zhengding 050803 Open Laboratory of Saline Lake Resources and Environment, chinese academy of geological sciences, beijing 10003. Zheng Mianping institute of Mineral Resources, chinese academy of geological sciences, beijing 10003. Research & Development Center of Saline Lake and Epithermal Deposit, chinese academy of geological sciences, beijing 10003. Wang Weiming Nanjing institute of geology and Palaeontology, chinese academy of sciences, Nanjing 2.0008 institute of Hydrogeology and Environmental geology Chinese Academy of Geological Sciences Zhengding 050803 Open Laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing 100037 institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 Research & Development Center of Saline Lake and Epithermal Deposit Chinese Academy of Geological Sciences Beijing 100037 Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008

This paper reports our primary effort in the quantitative reconstruction ofpaleoclimate based on the thrine in phytoecology of the affinity parent plants in the stratigraphicpollen records. The Eocene pollen data come from our former study on the Mingjia borehole 1 in theJianghan basin. The fluctuating trend in the parameter curve of climate shows that the climate inthe Middle Eocene in the Jianghan basin was more or less comparable with that of the present2.°―2.°N, characteristic of a humid, semi-humid central-southern subtropical climate. The annualtemperature at that time dropped by 1 ℃― 4 ℃ in the Late Eocene, approximately equal to that ofthe present 2.°―2.°N of northern-central subtropical climate. However, the climate composite atthat time, characterized by higher temperature, small annual range and big fluctuation inprecipitation, was quite different from the present one. The average temperature in January in theMiddle Eocene, higher than that of today, ranged between 5 ℃ and 9 ℃, indicating that no effect ofwinter monsoon occurred in the Middle Eocene, though such an effect may have occurred occasionallyin the Late Eocene. Major temperature decline is recognized at the depth of 2.100 m in the borehole,as was indicated by the decline in average January temperature, the increase in annual range, andthe increase in the deciduous broad-leaved types of trees in the spore-pollen assemblage. The sharpfluctuation in the annual precipitation, usually raging from 300 to 1 700 mm, was favorable for themigration and accumulation of salty deposit. When the precipitation was lower than 1 000 mm,ephemera shrub increased at the same depth as that of the salty deposit. It is, therefore, deducedthat the formation of the salty deposit was attributed mainly to the dry and hot environment in thehigh mountains and deep basins. The small annual precipitation and the intense fluctuation arefavorable for the sustainable accumulation of the salts, which is different from the present

关键词： quantitative reconstruction of paleoclimate annual range function ofthrine in phytoecology fuzzy mathematics eocene jianghan basin

The tectonic setting and geochemical characteristics of metamorphic basement in the southwest of the Yangtze Plate

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chinese Science Bulletin 1999年第S2期44卷 266-268页

作者： ZHANG Hongxiang~1, LIU Congqiang~2. HUANG Zhilong~2.and XU Zhifang~1 1. institute of Geophysics, chinese {2. of sciences, beijing 100101, china 2. institute of Geochemistry, chinese {2. of sciences, Guiyang 550002. china institute of Geophysics Chinese Academy of Sciences Beijing 100101 China institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE Dahongshan Group (in short DG) and its basement Dibadu Formation (in short DF) in the southeastof the Yangtze Plate are one of the oldest geological units in the Yangtze Plate. It is established in thisnote by means of geochemistry that the system of trench-arc-basin was formed by the subducting at thesouthwestern boundary of the Yangtze Plate in Lower Proterozoic Subera. And the existence of enrichedmantle EMI is argued by the way of trace elements geochemistry. 1 Regional geological setting There is a unit of the typical two-layer structure platform in the southwest of the Yangtze Plate. Themetamorphic basement of this platform is made up of Suberathem Dahongshan Group and SuberathemKunyang Group. Above them, there have covered expansive continental deposits from Mesozoic. The primary rocks of DG are composed of deposited limestone, sandstone and basalts. The basalts represent

关键词： Dahongshan Group(DG) Dibadu Formation(DF) tectonic geochemistry.

Tectono－Stratigraphic　Units　of　Western　Yunnan，　china　and　Their　Counterparts　in　Southeast　Asia

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Continental Dynamics 1996年第2期 123-133页

作者： Jin Xiaochi(institute of geology ,{2. academy of geological sciences, beijing 10003., china)

Ｔｅｃｔｏｎｏ－ＳｔｒａｔｉｇｒａｐｈｉｃＵｎｉｔｓｏｆＷｅｓｔｅｒｎＹｕｎｎａｎ，ＣｈｉｎａａｎｄＴｈｅｉｒＣｏｕｎｔｅｒｐａｒｔｓｉｎＳｏｕｔｈｅａｓｔＡｓｉａ￥ＪｉｎＸｉａｏｃｈｉ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏ... 详细信息

Ｔｅｃｔｏｎｏ－ＳｔｒａｔｉｇｒａｐｈｉｃＵｎｉｔｓｏｆＷｅｓｔｅｒｎＹｕｎｎａｎ，ＣｈｉｎａａｎｄＴｈｅｉｒＣｏｕｎｔｅｒｐａｒｔｓｉｎＳｏｕｔｈｅａｓｔＡｓｉａ￥ＪｉｎＸｉａｏｃｈｉ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎｅｓｅＡｃａｄｅ...

关键词： tectono-stratigraphic unit western Yunnan Southeast Asia

PALAEOECOLOGICAL, PALAEOCLIMATOLOGICAL AND PALAEOGEOGRAPHICAL STUDY OF QUATERNARY FORAMINIFERAL FAUNA IN china

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海洋地质与第四纪地质 1983年第1期 16-36页

作者： Lin Jingxing (institute of geology,{2.,beijing)

Quaternary foraminiferal faunas in china fall into five distinct categories according to palaeo-ecologicafeatures,namely:***-Bohai foraminiferal *** Pleistocene foraminiferal fauna in ***-epicontinental foraminiferal ***-East china Sea foraminiferal ***-South china Sea foraminiferal faunaBy correlating world zoogeographical zones of planktonic foraminifera and analysing the diversity in Quaternary foraminifera and ostracoda found in the North china Plain,it is possible to plot a graph of changes inpalaeo-climate since the Quaternary ***-ecological studies of Holocene foraminifera on the Fujianseaboard in southern china showed that Holocene foraminifera can be broken down into three climatic *** findings of these studies providea a basis for discusssion of the palaeo-geographic variations occurted inthe Palaeo-Bohai,the Palaeo-East china Sea and the Palaeo-South china *** the basis of the distributionof standard foraminifera in time

关键词： In PALAEOECOLOGICAL,PALAEOCLIMATOLOGICAL AND PALAEOGEOGRAPHICAL STUDY OF QUATERNARY FORAMINIFERAL FAUNA IN china