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Chinese Science Bulletin 1999年第S2期44卷 203-204页

作者： DING Zhenju~(1,2. and LlU Congqiang~1 1. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. china {2. of Ceosciences, Wuhan 430074, china Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China china university of Geosciences Wuhan 430074 China

THE Yangba Formation of Bikou Group is located in south Qinling, a famous orogenic belt separating Chinese continent into two parts: North china plate and Yangtze plate. The Yangba Formation comprises themafic and felsic volcanic rocks formed in an ancient seafloor environment during Proterozoric era. Thesuites of mafic and felsic volcanic rocks petrochemically are divided into tholeiite and calc-alkalinedacite, respectively, showing clearly characteristics of bimodal volcanic rock mainly with lithology andmajor element composition, and a lack of typical intermediate rocks. These indicate that the volcanicrocks of Yangba Formation were generated in rift tectonics setting. The tholeiites of Yangba Formation are similar in trace element compositions to Mid-ridge basalt,displaying a slight depletion to enrichment in light rare earth elements (LREEs) (La/Yb_n=0.6-1.4).slight fractionation between LREE (La/Sm_n=0.55-1.14) and HREE (Gd/Lu_n=1.09-1.50),

关键词： trace element volcanic rocks tectonics.

Legal Method on Settling Disputes on Demarcation over the east china Sea and Territorial Confict Between china and Japan

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学术界 2010年第5期 263-266页

作者： Guan Jianqiang east china {2. of Political science and Law

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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Science china Earth Sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3, CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china 2. Graduate university of Chinese Academy of Sciences, Beijing 100039, china 3. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 2.0008, china 1. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate university of Chinese Academy of Sciences Beijing 100039 China 3. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Transition from platemargin to intraplate environment: Geochemistry of basalts in Paleogene Liaohe basin, northeastern china

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Science china Earth Sciences 2005年第12期48卷 2069-2080页

作者： WU Changzhi1, GU Lianxing1, REN Zuowei1,2. ZHANG Zunzhong1, CHEN Zhenyan2.& ZHAO Ming1 1. State Key Laboratory of Mineral Deposit Research (Nanjing university), Department of Earth Sciences, Nanjing university, Nanjing 2.0093, {2. 2. Exploration and Development Research Institute of Liaohe Oilfield Branch Company, Petro{2., Panjin 12.010, {2. 1. State Key Laboratory of Mineral Deposit Research (Nanjing university) Department of Earth Sciences Nanjing University 210093 Nanjing China 2. Exploration and Development Research Institute of Liaohe Oilfield Branch Company PetroChina 124010 Panjin China

Paleogene basalts from the Liaohe basin, northeastern china, are dominated by alkaline olivine basalts and olivine basalts. These basalts are generally enriched in high field strength elements (HFSE), depleted in large ion lithophile elements (LILE) and comparable to those of typical ocean island basalts (OIB). Positive anomalies of Ba, Sr and Zr with high Nb/U, U/Pb, Ce/Pb and Zr/Hf ratios imply that materials from an oceanic crust had been added to the mantle sources of the basalts. In addition, the basalts are generally depleted in Sr, Nd and Pb isotopes, indicating that an enriched mantle (EMI) and a depleted mantle (DM) sources were added to the OIB-like resource. Comprehensive research on lithosphere evolution and tectonic setting of the Liaohe basin and surrounding areas suggests that these basalts were derived by variable degrees of partial melt-ing from an upwelling asthenosphere mantle. Materials from an oceanic lithosphere were added to the source in company with Paleogene tectonic transition from platemargin to intraplate envi-ronment. Retreating and steepening of the subducting Pacific oceanic plate could be the main cause for the tectonic environment transition.

关键词： geochemistry, basalt, Paleogene, Liaohe basin, North china Block, eastern china.

Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth Sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2.& CAI YongEn2.1 Institute of Crustal Dynamics, china Earthquake Administration, Beijing 100085, china 2.Department of Geophysics, Peking {2., Beijing 100871, china 1. Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China 2. Department of Geophysics Peking University Beijing 100871 China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GPS observation station is most densely deployed in the world. The unprecedented GPS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GPS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2.102. Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 2..7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GPS temporal series data Chi-Chi earthquake

Model test of the tunnel subjected to high water pressure in Jinping Second Cascade Hydropower Station,china

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Science china(Technological Sciences) 2011年第S1期54卷 192-198页

作者： WANG JianXiu 1,2.FENG Bo 2.HU LiSheng 2.TIAN PuZhuo 2.SUI DongChang 2.TANG YiQun 1,2.&YANG Ping 1,2.1 Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji university,Shanghai 2.0092.china 2.Department of Geotechnical Engineering,Tongji university,Shanghai 2.0092.china 1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji University Shanghai 200092 China2. Department of Geotechnical Engineering Tongji University Shanghai 200092 China

In the area with high groundwater pressure,grout curtain is often adopted to reduce the water pressure on tunnel lining.A series of model tests for the diversion tunnel of the Jinping Second Cascade Hydropower Station,china,is designed to study the effect of grout *** impact of the thickness of grout curtain,permeability of grout curtain,internal water pressure and drainage inflow on the distribution of water pressure are *** results indicates that under un-drained condition,water pressure is equal to hydrostatic one no matter grout curtain is selected or not,water pressure under drained condition is far less than that of un-drained condition,drainage in tunnel can reduce tunnel water pressure *** same inflow,both increasing of thickness and decrease of hydraulic conductivity of grout curtain can reduce water pressure *** the same water pressure,the smaller inflow of grout curtain,the less volume of water to be *** impact of hydraulic conductivity of grout curtain is more obvious than that of *** increasing of internal water pressure,the water pressure of grout curtain increases too,and the water pressure increases nearly *** proposed thickness of grout curtain for the diversion tunnels is 16 m.

关键词： tunnel grout curtain water pressure model test

Pb isotope geochemistry of lead, zinc, gold and silver deposit clustered region, Liaodong rift zone,northeastern china

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Science china Earth Sciences 2005年第4期48卷 467-476页

作者： CHEN Jiangfeng1, YU Gang1, XUE Chunji2. QIAN Hui1, HE Jianfeng1, XING Zhi1 & ZHANG Xun1 1. School of Earth and Space Sciences, university of Science and Technology of china, Hefei 2.002., china 2. Department of Geology, Chang’an university, Xi’an 710054, china 1. School of Earth and Space Sciences University of Science and Technology of China 230026 Hefei China 2. Department of Geology Chang’an University 710054 Xi’an China

Pb isotopic analyses were reported for sulfide and hydrothermal carbonate minerals and marble of the Xiquegou lead-zinc, the Zhenzigou zinc-lead and the Gaojiapuzi silver deposits from the Qingchengzi ore field and the Beiwagou zinc-lead deposit in the west, Proterozoic Liaodong rift zone. Pb isotopic ratios of the marble from the Qingchengzi ore field range from 18.2. to 30.63 for 2.6 Pb/2.4Pb, 15.59 to 17.05 for2.7Pb/2.4Pb and 37.43 to 38.63 for 2.8Pb/2.4Pb. The marble gives a Pb-Pb isochron age of 182.±92.Ma, which is interpreted as the age of the metamorphism of the marble. Ore Pb, including Pb of sulfide and hydrothermal car- bonate minerals, from the Qingchengzi ore field shows limited variation with 2.6 Pb/2.4Pb=17.66- 17.96, 2.7 Pb/2.4Pb=15.60-15.74 and 2.8Pb/2.4Pb=37.94-38.60. In contrast, ore Pb from the Beiwagou deposit gives different Pb isotopic ratios with 2.6Pb/2.4Pb=15.68-15.81, 2.7 Pb/2.4Pb= 15.34-15.45 and 2.8Pb/2.4Pb=35.30-35.68. Pb of all deposits from the Liaodong rift zone is derived from the upper crust. Ore Pb of the Qingchengzi deposits is derived from a young upper crust. The model Th/U ratios of 4.40 to 4.74 for ore Pb are significantly different from that of 1.7 to 4.4 given by the marble of the Qingchengzi ore field, suggesting that marble is not the source of the ore Pb. Ore Pb of the Beiwagou deposit is extracted from its source and the deposit is formed at the Paleoproterozoic era. Different Pb isotopic ratios of the Qingchengzi ore field and the Beiwagou deposit are due to different ages of the deposits and suggest that the two types of deposits are derived from different sources and are possibly formed by different ore-forming processes.

关键词： Pb isotopes, source(s) of the ore-forming materials, origin of ore deposits, Liaodong rift zone.

New stylophorans(Echinodermata) from the Upper Cambrian of Guangxi,South china

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Science china Earth Sciences 2008年第2期51卷 181-186页

作者： HAN NaiRen1 & CHEN GuiYing1,2.1 Department of Resources and Environmental Engineering, Guilin university of Technology, Gulin 541004, china 2.Faculty of Earth Sciences, china university of Geoscience, Wuhan 430074, china Department of Resources and Environmental Engineering Guilin University of Technology Gulin 541004 China Faculty of Earth Sciences China University of Geoscience Wuhan 430074 China

This paper describes for the first time the cornute stylophorans (Echinodermata) in china. The new material came from the Guole Formation of the Furongian (Late Cambrian) in the Guole area of Jingxi, Guangxi Province, South china. These new cornute specimens are preserved in situ and found along with well-preserved trilobites and brachiopods. One new species, Phyllocystis jingxiensis sp. nov., is proposed to accommodate these unusual materials. The new species is defined by the small, heart-shaped theca with the frame composed of ten narrow, smooth and thick marginal plates, three adoral plates and distinctive zygal and aulacophore. Both supracentrals and infracentrals are polygonal-outlined. The marginal plate M1' on the inferior face extends posteriorly to form zygal that possesses a broadened proximal end and the proximal portion joining with the conjunction between M4 and M5 on the inferior face. Aulacophore comprises ten segments at its proximal part and is conical at the middle part (named stylocone). Its distal portion is rather long and bears conspicuous ambulacrum grooves. Tectals are horizontally arranged on superior face and obliquely arranged on inferior face. Both cothurnopore and anal pyramid are vaguely seen on the right anterior corner and the extremity of theca's superior face.

关键词： Phyllocystis Stylophora Echinodermata Cambrian Guangxi South china

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 2. Faculty of Earth Sciences and Mineral Resources, china {2. of Geosciences, Beijing 100083, china 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, china 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

A STUDY ON LANDSCAPE MOSAIC STRUCTUREIN URBANRURAL AREA IN NORTHWESTOF china WITH RS AND GIS- A Case Study of Xigu District in Lanzhou City

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Chinese Geographical Science 2001年第4期11卷 80-90页

作者： XU Jian-hua1, LU Yan1, AI Nan-shan2. YUE Wen-ze3(1. Department of Geography, east china Normal {2., Shanghai 2.0062. P. R. china 2. Environmental Science and Engineering School, Sichuan {2., Chengdu 610064, P. R. Chin Department of Geography East China Normal University Shanghai P. R. China Environmental Science and Engineering School Sichuan University Chengdu P. R. China Department of Geography Lanzhou University Lanzhou P. R. China

ABSTRACT: At the study area of Xigu District in Lanzhou City, using RS & GIS as tools we apply Diversity, Dominance, Fragmentation , Isolation and so on to study the quantitative, fractal and spatial characters of landscapes’ structures in the four sub-regions divided by the morphological features. Using the Fractal Theory to establish the fractal structure models, we analyze the complexity and stability of various landscapes’ distribution with fractal dimension value. The spatial distribution characteristics of landscape mosaic structure are also expounded. At the end of the paper we discuss the relevant problems on the main factors which control and effect on the spatial pattern of landscapes as well as on landscape optimization and management.

关键词： landscape mosaic spatial structure fractal Xigu District in Lanzhou City