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Acta Geologica Sinica(English Edition) 1999年第2期73卷 208-215页

作者： LI Jinyi, WANG Zongqi and ZHAO Min institute of geology, chinese academy of Geological {4., Beijing 100037 chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

Silurian, Devonian and Carboniferous geological bodies in the Mianxian-Lueyang (Mian-Lue) collisional belt (MLB) and its neighbouring areas, southern Qinling Mountains, china, show similar characteristics of having undergone deformation of two stages. The earlier one, which is inferred to be related to collisional orogeny between the Yangtze and Sino-Korean palaeocontinents based on previous geological data, is responsible for large-scale, north-verging recumbent folds and overthrusts, and associated with low greenschist fades metamorphism. 4.Ar/39Ar dating of three muscovite samples taken from different localities yields plateau ages of 226.9±0.9 and 219.5±1.4.Ma and an apparent age of 194.5±3.0 Ma. Thus, the late Triassic collision between the Yangtze and Sino-Korean palaeocontinents has been constrained.

关键词： Qinling Mountains Mian-Lue collision belt muscovite 4.Ar/39Ar dating collisional orogeny

Changes of the aridity index in the arid regions of northwestern china since the Late Pleistocene-An understanding based on climatic geomorphology

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Changes of the aridity index in the arid regions of northwes...

中国科学院地质与地球物理研究所2002学术年会

作者： Yang Xiaoping institute of geology and geophysics,chinese {4. of sciences,100029 Beijing,china

The objective of this study was to reconstruct late Quaternary changes of the aridity index in the desert regions of northwester *** author made use of the system of climatic geomorphology as the main research method to overcome the problem of the lack of long sedimentary sequences in the *** inventory of landscape types was established by interpretation of air photos,satellite images and field *** comparing the present landscape types to the morphodynamics and relict landforms of older landscapes,it is concluded that the climate of the deserts of northwestern china during the High Glacial of the last glaciation and during the Early Holocene was much more humid than at *** conclusion is supported by research on lake level changes both within the deserts and in adjacent regions.

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Uncertainty in magnetic activity indices

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Uncertainty in magnetic activity indices

中国科学院地质与地球物理研究所2008学术年会

作者： XU WenYao institute of geology and geophysics,chinese {4. of sciences,Beijing 100029,china

Magnetic activity indices are widely used in theoretical studies of solar-terrestrial coupling and space weather ***,the indices suffer from various uncertainties,which limit their application and even mislead to incorrect conclusion. In this paper we analyze three most popular indices,Kp,AE and *** categories of uncertainties in magnetic indices are discussed:"data uncertainty" originating from inadequate data processing,"station uncertainty" caused by incomplete station covering,and "physical uncertainty" stemming from unclear physical mechanism.A comparison between magnetic disturbances and related indices indicate that the residual Sq will cause an uncertainty of 1—2 in K measurement, the uncertainty in saturated AE is as much as 50%,and the uncertainty in Dst index caused by the partial ring currents is about a half of the partial ring current.

关键词： magnetic activity indices Kp AE Dst solar-terrestrial coupling space weather

Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. Lanzhou institute of geology, chinese academy of sciences, Lanzhou 730000, china 2. Earthquake Research institute of Lanzhou, SSB, Lanzhou 730000, china 3. institute of Oceanology, chinese academy of sciences, Qingdao 266071, china Lanzhou institute of geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of Lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science china Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2. Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 51064., china 1. chinese academy of sciences SKLLQG Institute of Earth Environment 710075 Xi’an China 2. chinese academy of sciences Guangzhou Institute of Geochemistry 510640 Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

Sedimentological studies of aeolian sands in chinese deserts

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Sedimentological studies of aeolian sands in Chinese deserts

中国科学院地质与地球物理研究所2002学术年会

作者： YANG Xiaoping institute of geology and geophysics,chinese {4. of sciences,100029 Beijing,china

The objective of this study has,been to analyse the sedimentological properties of the dune sand in chinese *** were from the Taklamakan Desert in southern Xinjiang and from the Badain Jaran Desert in western Inner *** examination included particle size,heavy minerals and micro-textures on the quartz *** is fount out that the sand in the Taklamakan is finer than in the Badain *** weathering during the glaciations was thought to be responsible for small grain *** content of heavy minerals in the Taklamakan is higher than in the Badain *** addition,the percentage of unstable,moderately stable minerals in the Taklamakan is higher than in the Badain *** is concluded that the percentage of stable and very stable minerals increases from west to east in the deserts of northern china,reflecting the regional changes of the intensity of chemical *** with warm deserts in Africa,the sand of chinese deserts is characterized by small grain size and by high percentage of unstable and moderately heavy *** differences were presumably caused by the temperature difference and palaeoenvironmental histories.

关键词： geomorphology sedimentology desert aeolian sand china

Discussion on measurement and calculation principle of petrogenetic depth

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chinese Science Bulletin 1999年第24期44卷 2293-2295页

作者： LU Guxian and LIU Ruixun institute of Geomechanics , chinese academy of Geological sciences , Beijing 100081 ,{4. Department of geology, Peking University, Beijing 100871,{4. institute of Geomechanics Chinese Academy of Geological Sciences Beiing China Department of geology Peking University Beijing China

Geologic and geophysical data certificate that lithosphere and its down rock behave as solid, therefore,it is better to measure petrogenetic and metallogenetic depth according to internal stress of solid states. Lithomechanic experiment found that the bigger the confining pressure, the bigger the tensile and shear strength of rocks,so rock can bear very high differential stress but it is not broken. Sibson put forward that the property of rocks under 10-15km of the surface changes from brittle to ductile (rather than from elastic to plastic). Rock with ductile de-

关键词： petrogenetic depth solid stress state tectono-original additional hydrostatic pressure rock strength.

Climate Change and Desertification with Special Reference to the Cases in china

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Climate Change and Desertification with Special Reference to...

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： Xiaoping Yang institute of geology and geophysics,chinese {4. of sciences,Beijing 100029,china

This chapter briefly reviews the terminological origin,development and the latest status of desertification and demonstrates the significant impact of the climatic variations in the processes of desertification and its *** typical arid regions at Asia’s middle latitudes are selected as cases for studies, i.e.,the oases in the hyper-arid Taklamakan Desert in the west and the semi-arid Hunshandake Sandy Land in the east(Fig.1).It shows that humans set up cultivation bases in the center of the Taklamakan Desert over 2,000 years ago and the later abandonment of these bases was probably caused by decrease in runoffs associated with *** shaping the landscape changes between soil formation and aeolian sedimentation in the Hunshandake,the role played by the Holocene changes of East Asia summer monsoons surpasses the impact of human activities since the Neolithic time,meaning that the climatic background and its potential changes should be given greater attention in the aims and schemes of combating desertification. The rapid vegetation regeneration in recent years in the Hunshandake reconfirms the great importance of climatic background in ecological rehabilitations in desertified *** the course of global warming,the risks of desertification are likely to increase in both areas due to different reasons.

关键词： Desertification Climatic change Oasis Arid zone Semiarid area china

Mesozoic subduction-accretion zone in northeastern South china Sea inferred from geophysical interpretations

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Science china Earth sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2, WANG Jialin3, PANG Xiong4. CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea geology, South china Sea institute of Oceanology, chinese academy of sciences, Guang- zhou 510301, china 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054. china 3. Key Laboratory of Marine geology, Tongji University, Shanghai 200092, china 4. china National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, china 5. china National Offshore Oil Co. Limited – Research Center, Beijing 100027, china 1. Key Laboratory of Marginal Sea geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. College of Geological and Topographical Engineering Chang’an University Xi’an 710054 China 3. Key Laboratory of Marine geology Tongji University Shanghai 200092 China 4. china National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen 518067 China 5. china National Offshore Oil Co. Limited — Research Center Beijing 100027 China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South china Sea at approximately NE4.0 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South china. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South china Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE Asia, NE South china Sea, geophysics.

Geothermal Characteristics and Geological Implications of Major Tectonic Units in china

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Journal of Earth Science 2000年第3期19卷 152-157页

作者： Wang Yang Faculty of Earth sciences and Mineral Resources, china University of Geosciences, Beijing 100083, china Wang Jiyang {4. of geology and geophysics, chinese academy of sciences, Beijing 100029, china Deng Jinfu Faculty of Earth Scie

On the basis of more than 900 heat flow data in china and the surrounding seas, the authors study the geothermal characteristics of major tectonic units in china. The spatial pattern of heat flow and other thermal parameters for lithosphere exhibit significant lateral variation, originating from the Cenozoic tectonothermal activities related to the subduction of the Pacific plate and the collision between India and Asia. The mechanical strength of the crust and the seismicity of tectonic units were strongly affected by geothermal characteristics of units. The crustal heat production rate also shows the lateral heterogeneity, implying the significant lateral variation of bulk composition of the crust in china.

关键词： heat flow effective elastic thickness heat production rate of crust china.