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Summary of the Lithospheric Dynamics in China

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Acta Geologica Sinica(English Edition) 1987年第2期 15-29页

作者： ma xingyuan institute of geology, state seismological bureau, Beijing

This paper presents a summary of the explanatory notes for the 1: 4, 000.000 scale"Lithgspheric Dynamics map of China and Adjacent Seas". Which gives an outline of the geological and geophysical processes that are presently active or were once active during the Cenozoic. The focus is concentrated on intraplate phenomena and on explaining them in terms of fundamental plate tectonic *** lithosphere in China is very heterogeneous. Its dynamics can be described in terms of the relative motions of 8 active subplates and related 17 tectonic blocks, and the characteristics of neotectonic deformation. The present-day movement and deformation of the lithosphere in China, their relationship with the deep-seated processes, and the lateral heterogeneity, mass difference and stress state within it that will tend to cause crustal movement in the future are *** intraplate tectonics and stress field are mainly controlled by the heterogeneity of the lithosphere and the mode of interaction between subplates and their boundary conditions. The collision of the Indian plate with the Eurasian plate began and proceeded along the Tethys ocean side, which has produced a strong compressional stress in western China and brought about a high shear stress in the regions round the eastern and western corners of the Himalaya block. However, the eastern part of China is directly influenced by the western Pacific plate boundaries. The minimum principal stress here is tensional. which makes the shear stress high, it may be the cause of the high seismicity in North China and maritime region of southeastern China.

关键词： Summary of the Lithospheric Dynamics in China

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 Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, China 2. institute of{2., China seismological bureau, Beijing 10002., China Department of Earth Sciences and state Key Laboratory for Mineral Deposits Research Nanjing University Nanjing China institute of geology China Seismological Bureau 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.

EXPERIMENTAL STUDY ON DEFORmaTION FABRICS OF QUARTZ AND CALCITE IN SHEAR ZONE

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地震地质 1987年第4期 10-17页

作者： ma Sheng-li and ma Jin({2. of geology, state seismological bureau)

Frictional experiments of samples with quartz and calcite sandwich have been operated under certain confining pressures, strain rate and different temperatures. Samples deformed and undeformed have been studied by means of microscope, TEM, and U-Stage. On the basis of this, changes of deformation micro-structures and fabrics of quartz and calcite aggragates with temperatures under condition of simple shear have been analyzed.

关键词： Frictional experiment Shear zone Quartz Calcicte Microstructure Fabric

3D Velocity Structure and Its Tectonic Implications in the East China Sea and Yellow Sea

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Acta Geologica Sinica(English Edition) 1993年第3期67卷 273-296页

作者： Feng Rui, Zhou Hainan, institute of Geophysics, state seismological bureau, Beijing Yao Zhengsheng,{2. institute of Lanzhou, Lanzhou ma Guiming and Li Quanlin institute of Geophysics, state seismological bureau Beijing Fei Zhenbi

3D structure of the crust and upper mantle in the studied area has been analyzed from surface wave tomography. The velocity distribution in the uppermost crust is symmetrical on two sides of the central line of the sea, and coincides with the structure of crystalline basement. The essential difference in tectonics between the East China Sea and the Yellow Sea mainly lies in that the velocity structures of their lower crust and upper mantle are identical to those of South China and North China respectively. In the upper mantle there exists a high-velocity zone with a nearly EW strike from the Hangzhou Bay, China, to the Tokara Channel, Japan, along about the latitude of 30°N. It is found that between the East China Sea and the Yellow Sea there are systematical differences in geomorphology, geology, seismicity, heat flow, quality factor and gravity and aeromagnetic anomalies, which is related to both left-lateral shear dislocation and right-lateral tear of the Benioff zone from the Hangzhou Bay to the Tokara Channel.It is inferred that the East China Sea was formed by Cenozoic back-arc extension. The boundary between the North China and South China crustal blocks stretches along the southern piedmont of Mts. Daba-Dabie-Hangzhou Bay-Tokara Channel, and the subduction zone at the Okinawa trench is the eastern boundary of the South China crustal block. The movements of the Pacific plate, Indian plate and upper mantle rather than the Philippine plate subduction have played a dominant role for the modern tectonic movements in East Asia.

关键词： East China Sea and Yellow Sea 3D velocity structure surface wave tomography the Hang zhou Bay-Tokara Channel transform fault North China crustal block South China crustal block

SPATIAL DISTRIBUTION AND FRACTAL STRUCTURE OF AE FOCUSES OF INADA GRANITE UNDER TRIAXIAL COMPRESSION

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地震地质 1991年第2期 107-113页

作者： Lei Xing-lin, ma Jin(institute of {2., state seismological bureau, Beijing 10002.)Kusunose K., Nishizawa O., Satoh T.(Geological Survey of Japan, Tsukuba, 305 Japan)

An experimental study on the spatial distribution of the focuses of acoustic emissions of Inada granite (coarse grained granodiorite) under triaxial compression is reported in this paper. It is pointed out that AE locations is fractal with a dimension of 2.2.in average, lower than the result of Oshima granite (fine grained granodiorite), which is 2.7, under similar deformation condition. For Inada granite a band-limited fractal had been observed. Fractal dimension changed around grain size of the rock (RC = 5mm) Fractal dimension Ds and Dl (below and above the grain size, respectively) had different developing tendency. Ds and Dl can be considered as indicators of the inhomogeneity of stress field in corresponding scale.

关键词： Acoustic emission Microfracturing Three-dimensional focal location Fractal

Tectonic Interpretation of the Earthquake istribution in the Contiguous Continent of the United states

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Acta Geologica Sinica(English Edition) 1993年第2期67卷 151-165页

作者： ma Zongjin, Gao Xianglin, institute of {2., state seismological bureau, China Wang Qi, seismological bureau of Shandong Province, China L. Seeber and J. Armbruster Lamont-Doherty Geological Observatory, Columbia University, USA Jiang Minxi

With increasing high-quality geological and geophysical data it becomes clear that seismicity of the continents is characterized by linear patterns which are closely associated with tectonic features. The aim of this paper is to give reasonable interpretation for the earthquake distribution in the contiguous continent of the United states. Seismic lines and earthquake concentrated zones are defined, which reflect the characteristics of the continental seismotectonics. Similarities and differences in seismotectonics between the continental part of China and the contiguous continent of US are analysed. It is demonstrated that the spatial distribution of earthquakes can provide the information of the active structures in the earth's crust. The authors consider that the patterns of continental seismotectonics are not only controlled by the pre—existing tectonic frameworks and the current boundary dynamic conditions, but also possibly affected by dynamic factors of global tectonics at a higher level.

关键词： patterns of earthquake epicenters seismic lines seismotectonic features

Estimation of Potential Risk of Reservoir-Induced Earthquake for the Proposed Hydroelectric Project on the Yangtze Gorges

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Earthquake Research in China 1995年第4期9卷 42-51页

作者： Hu Yuliang,Zhao Meng,Hu Ping,ma Wentao,Yang Qingyuan,and Chen Xiancheng institute of {2.,state seismological bureau,Beijing 10002.,China

The proposed hydroelectric project on the Yangtze Gorges will be one of the largest power stations in the *** problem of induced seismicity to the project has attracted much attention throughout China and the world.A research program has been carried out by the state seismological bureau of *** on the size of the reservoir and the lithology,geological structure,permeability,stress state,and previous seismicity in the region,the potential risk of reservoir-induced seismicity has been *** results suggest that,after impoundment in the reservoir area,the possibility of induced seismicity cannot be completely ruled *** areas with potential risk {2.y be in some gorges composed of karstified carbonate and plutonic granite around the dam ***,the {2.gnitude is expected to be limited owing to the s{2.ll dimension of the induced seismogenic faults.

关键词： seismic risk evaluation reservoir earthquake Yangtze Gorge project

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青藏高原地球动力学初探

现代地质 1988年第2期 194-206页

作者：郑剑东国家地震局地质研究所

青藏高原是当今世界上最高、最大和最年轻的高原。青藏高原的地球动力学研究是一个复杂而饶有兴趣的问题。本文试图从高原的范围、地球物理特征、地震活动、构造演化和新构造运动等方面探讨其地球动力学过程。从新构造分析,笔者着重指... 详细信息

青藏高原是当今世界上最高、最大和最年轻的高原。青藏高原的地球动力学研究是一个复杂而饶有兴趣的问题。本文试图从高原的范围、地球物理特征、地震活动、构造演化和新构造运动等方面探讨其地球动力学过程。从新构造分析,笔者着重指出,青藏高原是欧亚大陆板块中最活动的一个块体,它在造就中国乃至东亚新构造运动的格局方面,是一个十分重要的因素。

关键词：青藏高原地球动力学岩石圈地球物理特征地震活动构造演化新构造运动

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关于元谋人化石地质时代的讨论

人类学学报 1983年第1期 40-48页

作者：刘东生丁梦林中国科学院地质研究所国家地震局地质研究所

根据对元谋组(广义)的岩石地层,古生物地层和磁性地层的重新认识,确认由广义的元谋组建立上新统沙沟组、下更新统元谋组(狭义)和中更新统上那蚌组的划分。元谋人化石产出在上那蚌组,时代为中更新世,处在古地磁极性柱的布容正向期的底部... 详细信息

根据对元谋组(广义)的岩石地层,古生物地层和磁性地层的重新认识,确认由广义的元谋组建立上新统沙沟组、下更新统元谋组(狭义)和中更新统上那蚌组的划分。元谋人化石产出在上那蚌组,时代为中更新世,处在古地磁极性柱的布容正向期的底部,其时代应不超过73万年,即可能为距今50—60万年。

关键词：元谋人年代中更新世