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A new inverse filtering method of gravity field

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Acta Oceanologica Sinica 1988年第3期7卷 421-434页

作者： JIN XIANGLONG and GAO ZHIQING Second institute of Oceanography, State Oceanic Administration, Hangzhou, china institute of Marine geology, Ministry of geology and Resources, Qingdao, china Second Inst. of Oceanography State Oceanic Administration Hangzhou China China

A new method for inversion of gravity field using the technique of inverse filtering is presented in this paper to calculate the structure of *** inversing gravity data of West Pacific and Okinawa Trough, it has been proven that the method of inverse filtering has many advantages, such as high accuracy, fast convergence rate, small memory space used and arbitrary reduction of sampling interval. This new method is convenient to minicomputer for solving the inverse problem of crustal structure.

关键词： A new inverse filtering method of gravity field

Redetermination of the Crystal Structure of Vesignieite

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 145-151页

作者： Ma Zhesheng He Ruilin Zhu Xiaoling china University of Geosciences institute of geology and Mineral Resources, Shaanxi institute of Mineral Depostis, Chinese Academy of Geological Sciences china University of Geosciences China

Vesignieite, Cu_3Ba(VO_4)_2(OH)_2, crystallizes in space group C_2 / m with a°=1.0270(2), b°=0.5911(1),c°=0.7711(2)nm and β=116.42(3)°. The intensity data were collected with the RIGAKU RASA-IISsingle-crystal four-circle diffractometer. The structure was determined by Patterson and Fourier methods andrefined by the least-square technique to a final R index of 0.051 for 614 independent diffraction points with|F? |>3σ|F?|. The crystal structure analysis shows that vesignieite has a layer structure parallel to (001). The powder diffraction lines were reindexed.

关键词： Redetermination of the Crystal Structure of Vesignieite

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Cenozoic terrestrial palynological assemblages in the glacial erratics from the Grove Mountains, east Antarctica

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Progress in Natural Science:Materials International 2009年第7期19卷 851-859页

作者： Aimin Fang a, Xiaohan Liu b, Weiming Wang c, Feixin Huang b, Lianjun Yu a a institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china b institute of Tibet Plateau Research, Chinese Academy of Sciences, Beijing 100029, china c Nanjing institute of geology and Palaeontology, Chinese Academy of Science, Nanjing 210008, china institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100029 China Nanjing institute of geology and Palaeontology Chinese Academy of Science Nanjing 210008 China

Fossiliferous glacial erratics have been found in moraines of the Grove Mountains, east Antarctica since 1998 by Chinese National Antarctic Research Expedition (CHNARE) teams. These erratics were derived from a suite of glaciogene strata hidden beneath the Antarctic Ice Sheet in the Lambert glacier drainage system, and thus provide a record of Cenozoic paleoenvironmental conditions and fossil biotas that are so far unknown from outcrops and drill cores in this region. By microfossil analysis, sparse Neogene spores and pollen grains are revealed, including: Toroisporis (Lygodiaceae), Granulatisporites (Pteridaceae?), Osmunda (Osmundaceae), Polypodiaceae, Magnastriatites (Parkeriaceae), Deltoidospora, Araucariaceae, Taxodiaceae, Podocarpus (Podocarpaceae), Dacrydium (Podocarpaceae), Pinus (Pinaceae), Keteleeria (Pinaceae), Picea (Pinaceae), Tsuga (Pinaceae), Chenopodiaceae, Artemisia (Asteraceae), Asteraceae, Gramineae, Fraxinoipollenites (Oleaceae), Oleoidearumpollenites (Oleaceae), Oleaceae, Operculumpollis, Nothofagidites (Nothofagus), Rhus, Quercus (Fagaceae), Juglans (Juglandaceae), Pterocarya (Juglandaceae), Liquidambar (Hamamelidaceae), Ulmus (Ulmaceae), Ulmoidepites (Ulmaceae), Tilia, Proteacidites (Proteaceae) and Tricolpopollenites; but without any marine diatoms. Most of the spores and pollen grains in the erratics are considered to originate from local sources except for some older exotic components that might be recycled from the basement sedimentary rocks by the ice sheet, so they are in situ sporo-palynological assemblages. Furthermore, since the source areas of the glaciogenic sedimentary rocks are assumed to be local or in the up glacier areas, the palynological assemblages in these erratics represent an inland terrestrial flora during a warmer period of the ice-sheet evolutionary history. The ages of these erratics are also discussed based on the occurrence of some diagnostic pollens such as the Artemisia, Chenopodiaceae and Nothofagus, which implies

关键词： East Antarctica Grove Mountains Glacial erratics Spores and pollen Neogene

New species and new records of diatoms from Lake Fuxian,china

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Journal of Systematics and Evolution 2010年第1期48卷 65-72页

作者： 1 Yan-Ling LI 1 Zhi-Jun GONG 2 Chun-Chao WANG 1 Ji SHEN 1(State Key Laboratory of Lake Science and Environment,Nanjing institute of Geography and Limnology,Chinese Academy of Sciences,Nanjing 210008,china) 2(Nanjing institute of geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china) (State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China) (Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China)

One new species,four newly recorded genera,and two newly recorded species of diatoms are described from *** are Sellaphora fuxianensis ***,Sellaphora Mereschkowsky,Karayevia Round & Bukhtiyarova,Placoneis Mereschkowsky,Fallacia Stickle & Mann,Placoneis prespanensis Levkov,Krstic & Nakov,and Fallacia lucinensis(Hustedt) *** taxa were collected from Lake Fuxian in Yunnan Province,*** species were observed with light and scanning electron microscopes,and their taxonomic characters are discussed.

关键词： china diatom new records new species.

Relationship between the TanLu Fault and Dabie Orogenic Belt in Eastern china

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Continental Dynamics 1999年第1期 53-61页

作者： WANG Yu institute of geology, china Seismological Bureau, Beijing 100029, china YANG Tiannan institute of geology, Chinese Academy of Geological Sciences, Beijing 100037, china

There are different and debated viewpoints on the relationship, evolutionary processes and dynamic models of the Tan Lu strike slip fault and Dabie orogenic belt. The Tan Lu fault, as a sinistral strike slip fault, evolved initially from the Middle Jurassic, but its real left lateral strike slip movement developed during 120-100 Ma. New geologic evidence indicates that the formation of the Tan Lu fault was based on the NE trending tectonic belts which were formed during the period from the Middle Jurassic to Early Cretaceous in eastern china. The Dabie orogenic belt underwent the following evolutionary processes: collision of two continental plates, extension and uplift, N verging thrusting and S verging thrusting, magmatic intrusion, then renewed extension and uplift. Later, it was cut by the Tan Lu strike slip fault in the eastern section. In the Jiaonan block (southern Shandong Peninsula), extensional processes are similar to that which evolved in the Dabie orogenic belt before the Middle Jurassic. Deformation appeared in the basement of some basins, such as the Hefei Basin, suggesting the tectonic transformation from E W trend to NE NNE strike during the Middle Jurassic to Early Cretaceous. All of the infor mation implies that the Tan Lu strike slip fault was not the result of the collision between the Yangtze and Sino Korean plates, nor was formed prior to the collisional event. The NE trending tectonics in eastern china demon strates that the development of the Tan Lu fault was consistent with the formation of the west Pacific plate sub duction.

关键词： Tan Lu fault Dabie orogenic belt dynamic evolution eastern china

Thermal Structure and Rheology of the Upper Mantle beneath Guangdong and Hainan Provinces,china

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Continental Dynamics 1999年第1期 23-32页

作者： LIN Chuanyong and SHI Lanbin institute of geology, Seismological Bureau of china, Beijing 100029, china HAN Xiuling institute of geology, Chinese Academy of Sciences, Beijing 100029, china CHEN Xiaode institute of geology, Seismological Bureau

The geotherm and rheology of the upper mantle beneath Guangdong and Hainan Provinces are derived from the detailed study of spinel lherzolite and garnet websterite xenoliths from these areas. The constructed upper mantle geotherm is higher than the oceanic geotherm, but is slightly lower than those for the upper mantle beneath eastern china constructed by Xu et al. (1995) and for southeastern Australia constructed by O’Reilly et al. (1985). The high geotherm is considered to be related to the upper mantle diapir that occurred in this area. The crust mantle boundary defined by this geotherm is about 33 km deep, indicating the underplating of upper mantle materials. The rheologic features of the xenoliths show that the upper mantle beneath these areas was subjected to a relatively strong deformation process, which might be related to upper mantle diapir. During this process the differential stress might reach up to 50 MPa. As a result, high strain rate, low viscosity zones occurred at the depth of 65 km. These zones are believed to be upper mantle shear zone. The lithosphere asthenosphere boundary was deduced to be at the depth of about 85 km. All these results coincide well with the available geophysical data.

关键词： mantle xenolith upper mantle geotherm rheology Guangdong Province Hainan Province

Petrophysical and capillary pressure properties of the upper Triassic Xujiahe Formation tight gas sandstones in western Sichuan,china

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Petroleum Science 2011年第1期8卷 34-42页

作者： Ye Sujuan Lu Zhengxiang Li Rong Exploration and Production Research institute Sinopec Southwest CompanySichuan 610081China Chengdu institute of geology and Mineral Resources Sichuan 610081China

The tight sandstones of the Upper Triassic Xujiahe Formation（T_3x） constitute important gas reservoirs in western *** Xujiahe sandstones are characterized by low to very low porosity （av.5.22%and 3.62%） for the T_3x^4 and T_3x^2 sandstones,respectively）,extremely low permeability（av. 0.060 mD and 0.058 mD for the T_3x^4 and T_3x^2 sandstones,respectively）,strong heterogeneity,micronano pore throat,and poor pore throat *** a result of complex pore structure and the occurrence of fractures,weak correlations exist between petrophysical properties and pore throat size,demonstrating that porosity or pore throat size alone does not serve as a good permeability *** improved correlations can be obtained between permeability and porosity when pore throat radii are incorporated. Correlations between porosity,permeability,and pore throat radii corresponding to different saturations of mercury were established,showing that the pore throat radius at 20%mercury saturation（R_（20）） is the best permeability *** regression analysis and artificial neural network（ANN） methods were used to establish permeability prediction models and the unique characteristics of neural networks enable them to be more successful in predicting permeability than the multivariate regression *** addition, four petrophysical rock types can be identified based on the distributions of R_（20）,each exhibiting distinct petrophysical properties and corresponding to different flow units.

关键词： Western Sichuan upper Triassic Xujiahe Formation tight sandstones permeability porosity pore throat radius regression analysis artificial neural network

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A challenge to the concept of slip-lines in extrusion tectonics

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Geoscience Frontiers 2011年第1期2卷 23-34页

作者： Yadong Zheng~(a,*),Erchie Wang~b,Jinjiang Zhang~a,Tao Wang~c a Key Laboratory of Orogenic Belts and Crustal Evolution,Ministry of Education,School of Earth and Space Sciences, Peking University,Beijing 100871,china b institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china c institute of geology,Chinese Academy of Geological Sciences,Beijing 100037,china Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Wide-open V-shaped conjugate strike-slip faults in Asia are typically related to extrusion ***,the tectonic model based on the slip-line theory of plasticity has some critical problems associated with *** conjugate sets of slip-lines in plane deformation,according to the theory of plasticity should be normal to each another but,in reality,the angles between the conjugate strike-slip faults,which are regarded as slip-lines in extrusion tectonics in the eastern Mediterranean,Tibet-middle Asia,china and the Indochina Peninsular regions,are always more than 90°(on average～110°) in the direction of contraction. Another problem is that the slip-line theory fails to explain how,in some cases,e.g.,in the Anatolian area in the eastern Mediterranean,the extrusion rate is much higher than the indent *** two major problems are easy to solve in terms of the Maximum-Effective-Moment(MEM) Criterion that predicts that orientations of the shear zones are theoretically at an angle of 54.7°and practically at angles of 55°±10°with theσ- or contractional *** orientations of the strike-slip faults that accommodate extrusion tectonics are,therefore, fundamentally controlled by the MEM *** extrusion is along the MEM-orientations,the extruding rate is normally higher than the indenting rate.

关键词： Extrusion tectonics Slip-line Wide-open V-shaped strike-slip faults MEM-Criterion Strain rate

Carbon and Oxygen Stable Isotope Values and Microfossils at 41.4-4.5ka BP in Tai Co,Tibet,china,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1,2,*),LIU Junying~(1,3),MA Zhibang~(1,4),WANG Hailei~(1,2) and MA Nina~(1,2) 1 MLR Key Laboratory of Saline Lake Resources and Environment,institute of Mineral Resources,CAGS, Beijing 100037,china 2 Research and Development Center for Saline Lakes and Epithermal Deposits,Chinese Academy of Geological Sciences,Beijing 100037,china 3 institute of geology,Chinese Academy of Geological Sciences,Beijing 100037,china 4 Key Laboratory of Cenozoic geology and Environment,Chinese Academy of Sciences,Beijing 100029, china MLR Key Laboratory of Saline Lake Resources and Environment Institute of Mineral Resources CAGS Beijing 100037 China Research and Development Center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Cenozoic geology and Environment Chinese Academy of Sciences Beijing 100029 China

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>10 cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 41.4 to 4.5 ka BP:at 41.4-26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-17.5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 17.5-16.0 ka BP,it was slightly cold-dry;at 16.0-11.8 ka BP,it was slightly warm-wet;at 11.8-10.4 ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 10.4 ka BP,the temperatures began to rise again;at 10.4-9.4 ka BP,it was slightly warm-wet;at 9.4-8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(41.4-4.5 ka BP) Tai Co Tibet