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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. {2. of geology, china seismological {6., Beijing 10002., china 1. Department of Earth Sciences and state Key Laboratory for Mineral Deposits Research Nanjing University 210093 Nanjing China 2. institute of geology China Seismological Bureau 100029 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.

SEISMICITY TENDENCY PREDICTION BEFORE 2.2. IN china MAINLAND FROM ASTRONOMIC PERIODICITIES

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地震地质 1990年第1期 6-11页

作者： Du Pin-ren (institute of geology,{2. seismological bureau)

The correlations between large earthquakes in china continent and periodicities of the Moon’s movement and the solar activity are statistically analysed and the following points are revealed:1. The earthquakes with ≥7.5 in Qing-Zang fault-block region have 18.6.yr periodicity of the Moon’s nodes motion.2. The earthquakes with M≥7.1 in Xinjiang fault-block region have 8.85-yr periodicity of the Moon’s perigee motion.3. The earthquakes with M≥7.0 in china mainland have the tendency to cluster around times of minima of sunspot cycles and in the even solar cycles.4. The earthquakes with M≥8.0 in china continent have the tendency to cluster around the valley times of the secular cycles of the solar *** to above correlations, the prediction of seismicity tendency can be given as follows: In china continent, especially Western china, the current active seismic period should continue up to the end of this century. The next active period would be 2.06.2.15.

关键词： Ascending node Perigee Solar activity Seismicity

The Geoscience Transect from Xiangshui,Jiangsu Province to Mandal,Inner Mongolia

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 1-21页

作者： Ma Xingyuan Liu Changyuan Liu Guodong Jiang Minxi institute of geology,{2. seismological bureau,Beijing Geophysical Exploration Pafrty,{2. seismological bureau,Zhengzhou. 2.0} of geology State Seismological Bureau Beijing. 3Geophysical Exploration Party State Seismological Bureau Zhengzhou.

The Xiangshui to Mandal geoscience transect, which has a total length of 1,2.0 km, extends diagonally,from SE to NW, across the Sino-Korean plate and its ancient continental margin, passing through nine tectonicunits: the Subei-Jiaonan terrane, West Shandong block, North china rift basin, Taihang-Wutai block, Ordosblock, Hu-Bao (Hohhot-Baotou) Basin, Yinshan block and Inner Mongolian fold system. The graphic display of the transect is compiled according to the Guidelines for the Global GeoscienceTransect (GGT) Project on the basis of an integrated study of all available geological, geochemical andgeophysical data, thus bringing light to the process of cratonization of the Sino-Korean plate and its relation-ship with the transitional zone of the ancient continental margin, and the features of intraplate structures pro-duced by subsequent tectonic modifications and intraplate dynamics.

关键词： The Geoscience Transect from Xiangshui Jiangsu Province to Mandal Inner Mongolia

Analysis of Some Characteristics of the Fault Activities in Eastern china by Satellite Images

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 357-369,457-458页

作者： Xie Guanglin institute of Seismology,state {2. bureau institute of Seismology State Seismological Bureau

Active faults have special electromagnetic effect and remote sensing characteristics, and exhibit unique im-agery marks in satellite images. A comprehensive comparison of images of active faults in eastern china and ananalysis of geologic and geomorphic data can tell us some characteristics of fault activity in the area during theneotectonic period: 1) The fault activities of the north-south tectonic zone, North china and Taiwan werestronger than those of southeastern and northeastern china; 2. the faulting in the north-south tectonic zone,North china and Taiwan has continued up to now, and most of the fault activites in southeastern andnorth-eastern china have become weaker since the Middle Pleistocene; 3) the activity is unsteady in time, mostbeing intermittent, or episodic, i.e. alternately strong and weak; 4) most active faults of a definite size can be di-vided into several segments which somewhat differ from each other in the characteristics of the activity.

关键词： Analysis of Some Characteristics of the Fault Activities in Eastern china by Satellite Images

Magma underplating and Hannuoba present crust-mantle transitional zone composition: Xenolith petrological and geochemical evidence

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Science china Earth Sciences 2005年第8期48卷 1089-1105页

作者： FAN Qicheng1,2. ZHANG Hongfu1, SUI Jianli1, ZHAI Mingguo1, SUN Qian2.& LI Ni2.1. institute of geology and Geophysics, Chinese Academy of Sciences, Beijing {2., china 2. institute of geology, china seismological bureau, Beijing {2., china 1. institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of geology China Seismological Bureau 100029 Beijing China

On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic.

关键词： magma underplating, xenolith petrology, geochemistry, cust-mantle boundary constituent, Hannuoba.

GENETIC ANALYSIS OF ANOMALOUS VARIATION OF WATER TABLE IN CHANGPING WELL, BEIJING

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地震地质 1991年第4期 312-316+311页

作者： Yang Hui-nian(institute of geology,{2., Beijing 10002.)

Field investigation on hydrogeological environment around Changping well reveals that the anomalous uprise of ’water table begining from Oct. 1988 was mainly caused by the leakage of water from the channel leading to... 详细信息

关键词： Changping well Anomalous water table Shisanling Reservoir Paleochannel Water diversion Pecolation recharge

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern china:Implication for lithospheric evolution

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Science china Earth Sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1, SUI Jianli2. XU Ping2. LI Ni1, SUN Qian1 & WANG Tuanhua1 1. institute of geology,{2. seismological bureau, Beijing 10002.,{2. 2. institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 10002.,{2. 1. institute of geology China Seismological Bureau Beijing 100029 China 2. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern china (North china, Northeastern china and Southeastern china coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2.(6.%—6.%) and alkalis (K_2.+Na_2. = 5%—11%, especially for K_2.) as well asvolatiles such as H_2. and CO_2.(2.—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2. > 3%) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern china. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern china.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern china.

Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 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 {2., Chinese Academy of Geological Sciences, Beijing 100037, china 2. Development and Research Center, china Geological Survey, Beijing 100037, china 3. china University of Geosciences, Beijing 100083, china 4. china University of Geosciences, Wuhan 430074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812. china 6. institute of geology,{12., Beijing 10002., china 1. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of Geosciences 100083 Beijing China 4. china University of Geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. institute of geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, 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 china 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 china Platform is a remnant of cratonic lithosphere after the North china 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 china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china 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 china 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

LONGITUDINAL STREAM-PROFILES AS INDICATORS FOR GEOMETRIC SEGMENTATION OF THE LANGSHAN- HUANGBAISI FAULT ZONE, NORTHWEST BEIJING

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地震地质 1991年第4期 300-305+299页

作者： Cheng Shao-ping, Yang Gui-zhi and Yang Zhe(institute of geology,{2., Beijing 10002., china)

The Langshan-Huangbaisi fault zone in northwest Beijing is the southwestern part of the normal fault zone on the northern margin of the Yanqing basin, 35.5km long and NNE-NEE-trending in general, on which two major 130°- 140° bends separate it into three segments with different *** the Hack’s method, 71 longitudinal stream-profiles along the fault zone are analysed, shawing a well geomorphic response to the fault geometry. On these two major bends the gradient indices,K values, are relatively high. These three segments greatly differ in K *** stream-profiles are good tectonic-geomorphic indicators for geometric Segmentation of normal faults and will prqvide insight into segmented kinematics and paleoseismology.

关键词： Beijing Langshan-Huangbaisi fault zone Longitudinal stream-profile Geometric segmentatoin Gradient index