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chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, ZHANG Lifei & LIU Shengwei1. institute of geology, {2. academy of Geological sciences, Beijing 100037, china 2. Department of geology, Peking University, Beijing 100871, Chin institute of geology Chinese Academy of Geological Sciences Beijing China Department of geology Peking University Beijing China

The 40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （401 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （381 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （370-364 Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 40Ar/39Ar age.

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,{2., Lanzhou 730000, china 2. Earthquake Research institute of Lanzhou, SSB, Lanzhou 730000, china 3. institute of Oceanology,{2., Qingdao 2.6071, 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.

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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Science china Technological sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1,2.3, WAN WeiXing1, LIU LiBo1, NING BaiQi1, ZHAO BiQiang1 & ZHANG ManLian1 1 institute of geology and geophysics, chinese academy of sciences, Beijing 10002.,{2. 2.Wuhan institute of Physics and Mathematics, chinese academy of sciences, Wuhan 430071,{2. 3 Graduate University, chinese academy of sciences, Beijing 100049,{2. 1. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China 2. Wuhan institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China 3. chinese academy of sciences Graduate University Beijing 100049 China

The TIME-IGGCAS (Theoretical Ionospheric Model of the Earth in institute of Ge- ology and geophysics,{2.) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IRI, NeQuick-ITUR, and TItheridge temperature models) and multi-observations (GPS, Ionosondes, Topex, DMSP, FORMOSAT, and CHAMP) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

Atmospheric gravity Green's functions

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chinese Science Bulletin 1997年第20期42卷 1712-1719页

作者： SUN HepingLaboratory of Dynamic Geodesy, institute of Geodesy and geophysics,{2., Wuhan 430077, china Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China

THE observational accuracy of the superconducting gravimeter has now reached 0.1 μGal levelor better, with characteristics of the low noise, high sensitivity and better continuity and sta-bility. It will play an important part in the study of the change in (non-) tidal gravity signals,especially in the application of the geophysics and geodynamics. However, the instrument

关键词： air pressure Green’s functions atmospheric gravity admittance.

Landscape evolution and palaeoclimate in the deserts of northwestern china,with a special reference to Badain Jaran and Taklamakan

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chinese Science Bulletin 2001年第S1期46卷 6-11页

作者： YANG Xiaopinginstitute of geology and geophysics, chinese academy of sciences, Beijing 10002.,{2. (e-mail: xpyang@public2.east. ***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China

A comparative study of geomorphologic landscapes in the Badain Jaran Desert and Taklamakan Desert was made on the basis of field investigations, thermolumi-niscence and radiocarbon dating as well as analysis of sand grain texture. The sand seas of the Badain Jaran Desert differ greatly from that of the Taklamakan Desert in terms of dune morphology, interdune relief, dune stratigraphy and sand sources. The thermoluminiscence ages of the dunes suggest that the basic configuration of the megadunes in the Badain Jaran Desert has not changed at least since Middle Holocene. There were periods of more humid environment during the last glaciation and Holocene in both deserts, but events of higher precipitation in the Badain Jaran Desert were more frequent than in the Taklamakan. In both desert areas, aeolian processes have been intensified during the last 2.00 a.

关键词： desert sand seas palaeoclimate landscape northwestern china.

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and Earth’s Dynamics,institute of Geodesy and geophysics,{2. academy of sciences,Wuhan 430077,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3 institute of geophysics,Huazhong University of Science and Technology,Wuhan 430074,china 1. State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science china Earth sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2. TENG Jiwen2. LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. institute of Intelligent Instrument & Measurement Control Technology, Jilin University, Changchun 13002., china 2. institute of geology & geophysics, chinese academy of sciences, Beijing 10002., china 1. institute of Intelligent Instrument & Measurement Control Technology Jilin University 130026 Changchun China 2. institute of geology & {2. Chinese Academy of Sciences 100029 Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

Improved retracking algorithm for oceanic altimeter waveforms

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Progress in Natural Science:Materials International 2009年第2期19卷 195-203页

作者： Lifeng Bao,Yang Lu,Yong Wang institute of Geodesy and geophysics,{2. academy of sciences,Wuhan 430077,china [a]institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China

Over the deep oceans without land/ice interference,the waveforms created by the return altimeter pulse generally follow the ocean model of Brown,and the corresponding range can be properly determined using the result from an onboard tracker. In the case of com-plex altimeter waveforms corrupted due to a variety of reasons,the processor on the satellite cannot properly determine the center of the leading edge,and range observations can be in error. As an efficacious method to improve the precision of those altimeter observations with complex waveforms,waveform retracking is required to reprocess the original returning pulse. Based on basic altimeter theory and the geometric feature of altimeter waveforms,we developed a new altimeter waveform retracker,which is valid for all altimeter wave-forms once there exists a reasonable returning signal. The performances of the existing Beta-5 retracker,threshold retracker,improved threshold retracker,and the new retracker are assessed in the experimental regions (china Seas and its adjacent regions),and the improvements in the accuracy of sea surface height are investigated by the difference between retracked altimeter observations and ref-erenced geoid. The comparisons denote that the new algorithm gives the best performance in both the open ocean and coastal regions. Also,the new retracker presents a uniform performance in the whole test region. Besides,there is a significant improvement in the short-wavelength precision and the spatial resolution of sea surface height after retracking process.

关键词： Altimetry Waveform retracking Sea surface height

Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science china Earth sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2. WANG Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, Beijing 100083,{2. 2. institute of geology and geophysics, chinese academy of sciences, Beijing 10002.,{2. 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

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 10002.,{2. b institute of Tibet Plateau Research, chinese academy of sciences, Beijing 10002.,{2. c Nanjing institute of geology and Palaeontology, chinese academy of Science, Nanjing 2.0008,{2. [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

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