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中国科学院地质与地球物理研究所2008学术年会

作者： TAO XU~1.ZHONGJIE ZHANG~1,AIHUA ZHAO~2,ANJIA ZHANG~1,XI ZHANG~1 and HONGSHUANG ZHANG~1 1 State Key Laboratory of Lithosphere Evolution,institute of geology and Geophysics.Chinese Academy of Sciences,china. 2 institute of geology and Geophysics,china Earthquake Administration,china.

We model a complex 3D anisotropic structure as an aggregate of arbitrarily shaped blocks or volumes separated by triangulated interfaces,and different anisotropic parameters can be defined in different *** anisotropic media,seismic wave travels in the direction of ray vectors with group velocities throughout a ray trajectory,therefore,group velocities expressed by ray angles is required,but difficult to express in terms of phase *** approximate expression in terms of ray angles is derived for weak transversely isotropic media with a vertical symmetry axis(VTI).We also propose a simple iterative process to calculate ray angles in terms of the Snell’s law still valid for phase velocities and phase *** of shooting angles is crucial in implementing 3D shooting ray-tracing,and we suggest to use the sub-triangle shooting method to update the shooting angles to enhance the computing *** tests demonstrate that a blocky model can be a good description of complex 3D VTI media and the sub-triangle shooting ray-tracing is very effective to implement for kinematics two-point ray-tracing.

关键词： phase velocity group velocity Snell’s law ray-tracing.

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RADIOCARBON AND STABLE CARBON ISOTOPE ANALYSES OF LAND SNAILS FROM THE CHINESE LOESS PLATEAU:ENVIRONMENTAL AND CHRONOLOGICAL IMPLICATIONS

RADIOCARBON AND STABLE CARBON ISOTOPE ANALYSES OF LAND SNAIL...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Bing Xu·Zhaoyan Gu·Jingtai Han·Zongxiu Liu·Yunpeng Pei·Yanwu Lu·Naiqin Wu·Yongfu Chen 1Key Laboratory of Cenozoic geology and Environment,institute of geology and Geophysics,Chinese Academy of Sciences, Beijing 10029,china. 2 institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 10029,china. 4 china University of Geosciences,Beijing 100083,china.

Paired radiocarbon and stable carbon analyses have been carried out on aragonite shells and organic soft bodies of snails from the Chinese Loess Plateau in order to explore the possibility of using these kinds of samples as environmental and chronological *** show that the soft bodies exhibit C concentrations similar to those of plant leaves,indicating that carbon in the soft bodies is fixed from organic *** aragonite shells are depleted in C compared to the soft bodies due to ingestion of C-depleted *** depletion shows a consistent pattern across the Chinese Loess Plateau,implying a good potential for the snail shells to be applicable for C dating with a simple ***δC values measured for aragonite shells display a linear relationship with those obtained for the soft bodies with a constant offset. In addition,the carbon derived from organic diets accounts for more than 70%of the total shell *** fact suggests that stable carbon isotope composition of aragonite shells mainly reflects that of organic diet,and could be used as a reliable indicator of paleodiet in the Chinese Loess Plateau.

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Multisymplectic and Variational Integrators

Multisymplectic and Variational Integrators

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The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational MechanicsⅠ

作者： Mengzhao Qin, Jingbo Chen 1 institute of Computational Mathematics and Scientific/Engineering Computing, AMSS, Chinese Academy of Sciences, Beijing, 100080, china 2 institute of geology and Geophysics, Chinese Academy of Sciences, Beijing, china

Multisymplectic and variational integrators are presented from a comparative point of view in this paper. On multisymplectic integrators, we discuss their implementation issue and present composition methods for constructing higher order multisymplectic integrators. On variational integrators, we prove their equivalence to multisymplectic integrators. Several generalizations are also presented.

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Application of GIS-Based Mathematical Models into Regional Assessment of Geohazards in Three Gorges Reservoir Area

Application of GIS-Based Mathematical Models into Regional A...

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智能计算及其应用国际会议

作者： LUO Wenqiang1 HUANG Runqiu2 (1 Department of Mathematics and Physics china University of Geosciences Wuhan 430074 china) (2 institute of geology Engineering Chengdu University of Technology Chengdu 610059 china)

We presented application of GIS-based artificial neural network model, information theory model and fuzzy sets model into regional assessment of geohazards in Three Gorges Reservoir area. Using GIS fu

关键词： GIS mathematical models Three Gorges Reservoir area geohazards

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Mesozoic-Paleogene sedimentary facies and paleogeography of Tibet, western china: Tectonic implications

Mesozoic-Paleogene sedimentary facies and paleogeography of ...

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2001年全国沉积学大会

作者： Kai-Jun Zhang, Bangdong Xia , Xiwen Liang Department of Earth Sciences, Nanjing University, Nanjing 210093, china institute of Petroleum geology, Jianghan Petroleum Bureau, Qianjiang, Hubei 433124, china

＜正＞ In this paper, we report the results of sedimentary studies on the Mesozoic sequences of Tibet since 1996, sponsored by the General Petroleum Corporation of china and the Natural Science Foundation of china. In the Early-Middle Triassic, an abyssal sea covered most of the Songpan-Ganzi area whereas a named Central Tibetan Landmass up to 400 km wide could have stretched across the Lhasa and Western Qiangtang blocks. In the Late Triassic, the Songpan-Ganzi sea closed at the latest stage, the Central Tibetan Landmass got reduced westwards away from southern Western Qiangtang, a littoral environment dominated Eastern Qiangtang, middle Western Qiangtang, and southeastern Lhasa, a shelf environment existed only in northern and southeastern

关键词： Tibet Tethys Mesozoic Paleogene sedimentary facies Paleogeography tectonic reconstruction

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The Extensional Tectonics and Retrometamorphic Processes Subsequent to the High-Pressure and Ultrahigh-Pressure Metamorphic Events in Dabie-shan,china

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Continental Dynamics 1998年第Z1期 65-73页

作者： YOU Zhendong 1) , SUO Shutian 1) , ZHONG Zengqiu 1) , ZHANG Zeming 2) , WEI Bize 1) 1) china University of Geosciences, Wuhan, 430074, china 2) institute of geology, CAGS, 26 Baiwanzhuang Road, Beijing 100037, Ch

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｔｅｎｔｉｏｎｏｆｓｔｕｄｙｉｎｇＨＰａｎｄＵＨＰｍｅｔａｍｏｒｐｈｉｓｍｆｏｒｔｈｅｐａｓｔｄｅｃａｄｅｈａｓｂｅｅｎｐａｉｄｔｏＵＨＰｍｅｔａｍｏｒｐｈｉｃｍｉｎｅｒａｌｓａ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｔｅｎｔｉｏｎｏｆｓｔｕｄｙｉｎｇＨＰａｎｄＵＨＰｍｅｔａｍｏｒｐｈｉｓｍｆｏｒｔｈｅｐａｓｔｄｅｃａｄｅｈａｓｂｅｅｎｐａｉｄｔｏＵＨＰｍｅｔａｍｏｒｐｈｉｃｍｉｎｅｒａｌｓａｎｄｔｈｅｉｒｐａｒａｇｅｎｅｓｉ...

关键词： crustal extension ultrahigh pressure metamorphism decompressive retrograde metamorphism delamination underplating

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The oleaginous Botryococcus from the Triassic Yanchang Formation in Ordos Basin,Northwestern china:Morphology and its paleoenvironmental significance

The oleaginous Botryococcus from the Triassic Yanchang Forma...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Li-ming Ji~(a,*),Kui Yan~(b,c),Fan-wei Meng~(b,c),Min Zhao~(a,d) a Key Laboratory of Petroleum Resources Research,institute of geology and Geophysics,Chinese Academy of Sciences,Lanzhou,Gansu Province 730000,china b State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of geology and Palaeontology,Chinese Academy of Sciences,Nanjing,jiangsu Province 210008,china c Nanjing institute of geology and Palaeontology,Chinese Academy of Sciences,Nanjing,jiangsu Province 210008,china d Graduate School of Chinese Academy of Science,Beijing 100069,china

High abundance but rather low diversity algal fossils were found in the hydrocarbon source rocks of the Ch 7-2-Ch 7-3 section,Triassic Yanchang Formation in the Xifeng area of southwest Ordos Basin,which are mainly composed of prolific Leiosphaeridia and *** colonies are of various forms;the majority is nubbly,with some of cluster and cotton *** nubbly colonies appear globular, cordiform,ternate petal,obtuse triangle,chrysanthemum shape and so *** Botryococcus are saffron or brown and are frequently covered with clay under transmission microscope,and shows strong yellow and light brown under fluorescence *** could live in freshwater and brackish *** Botryococcus colonies that lived in fresh water are small with small single cells arranged radially,with undulant or indented *** Botryococcus colonies that lived in brackish water are bigger, with larger single cells arranged irregularly,with slippery *** most of Botryococcus are discovered from the organic-rich argillaceous sediment with abundant pyrites in the semi- and deep-lake facies,and shows they were preserved in low-energy reducing *** characteristics of various microfossils and the present of Pediastrum in the phytoplankton flora indicate that they are in situ or near *** lake area of the Ordos Basin was gradually expanding and reaching its most extensive flood surface in the Ch 7 of Yanchang Formation interval during the Middle and Late Triassic, with warm climate,plentiful rainfall,and luxuriant vegetation,as determined by the environmental analysis with Botryococcus in Xifeng *** presence of two ecological types of Botryococcus indicates that the salinity of lake water was fluctuating in the Ch 7 *** occurrence of symbiotic acritarchs and geochemical salinity indices show that the Ordos Lake was a typical fresh-water lake,which was gradually desalted,and its salinity fluctuation was narrow durin

关键词： Ordos Basin Triassic Yanchang Formation Hydrocarbon source rocks Botryococcus Paleoenvironment

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An overview of the crustal structure of the Tibetan plateau after 35 years of deep seismic soundings

An overview of the crustal structure of the Tibetan plateau ...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Zhongjie Zhang~(a,*),Yangfan Deng~(b,c),Jiwen Teng~a,Chunyong Wang~d,Rui Gao~e,Yun Chen~a,Weiming Fan~b a State Key Laboratory of Lithospheric Evolution,institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china b Guangzhou institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,china c Graduate University of Chinese Academy of Sciences,Beijing 100049,china d institute of Geophysics,china Earthquake Administration,Beijing 100081,china e institute of geology,Chinese Academy of Geological Sciences,Ministry of Land and Resources,Beijing 100037,china

Since the pioneer wide-angle seismic profile along the Yadong-Gulu rift acquired in 1974 by the ex-institute of Geophysics,Chinese Academy of Sciences(CAS),several research programs aimed to deep geophysics, performed thanks to the participation of Chinese national and international institutions,have been developed during last 35 years,including 23 wide-angle seismic profiles with total length of about 6000 *** profiles are unevenly distributed,most of them in eastern Tibet and few profiles in western *** this paper,we make a summarized presentation of all these wide-angle seismic profiles and provide an overall view of the seismic velocity structure of the crust beneath the broad Tibetan plateau, which is the product of the continuous convergence and collision of the Indian and Eurasian plates since about 50 Ma *** patterns of crustal thickness variation related to the tectonic blocks and along suture zones of the region are *** crust thickness is confirmed to be about 70-75 km under southern Tibet,and 60-65 km under northern,northeastern and southeastern *** leading edge of the subducted lithosphere reaches the northern margin of the plateau and directly contacts with Tarim *** of the 90°E boundary,the Indian crust is moving towards the northern edge of the plateau and collides with Tarim Basin at 80°E while reach the Bangong-Nujiang suture belt at 88°E;eastward of the 90°E boundary,the northern edge of the crust should be at 50-100 km south of Bangong-Nujiang *** results supply helpful constrains to understand the mechanism of the continent-continent collision and its consequences in the plateau and neighbouring areas.

关键词： Wide-angle seismic profiling Crustal thickness Tibetan plateau

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LATE JURASSIC AMMONITES FROM THE AMDO AREA OF THE NORTHERN TIBET AND THEIR PALAEOGEOGRAPHIC IMPLICATIONS

LATE JURASSIC AMMONITES FROM THE AMDO AREA OF THE NORTHERN T...

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第二届国际古生物学大会

作者： Lan CHEN, Haisheng YI, Hong ZHONG , Ruizhong HU Chongqing University of Science and Technology, Chongqing 400042, china. institute of Petroleum Engineering, Chongqing University of Science and Technology, Chongqing 440002, china institute of Sedimentary geology, Chengdu University of Technology, Chengdu 650019, china

A Late Jurassic succession consisting predominately of black shales, dark grey calcareous mudstones and marls with abundant ammonites occur in the 114 Station section in the Amdo area of the northern Tibet. These strata differ conspicuously in regards to their sediments and fauna from the widespread Yanshiping Group of the Qiangtang Basin. We have adopted the Qiangmuleiqu Formation as a regional lithostratigraph-

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误差曲线中极值E,F表示任意方向位差的推导

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四川测绘 1996年第3期19卷 134-134页

作者：周世健华东地质学院

文献[1]对这一公式的推导较为繁琐，不易理解，且理论性不强，给教学带来不便，本文则给出一简洁的推导，而且其原理较为严密和简单，学生易于掌握。

关键词：误差曲线极值位差任意方向测量

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