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A Study of the Kunlun-Qilian-Qinling Suture System

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 364-374页

作者： BIAN Qiantao, GAO Shanlin, LI Dihui, YE Zhengren, CHANG Chengfa, LUO Xiaoquan institute of geology and geophysics, chinese academy of sciences, beijing 100029 science Press, chinese academy of sciences, beijing 100717 chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China chinese Acad Sci Beijing 100717 Peoples R China

The Late Neoproterozoic-Early Palaeozoic suture zones within the Central Orogenic Belt of china can be considered a system—the Kunlun-Qilian-Qinling suture system (KQQ suture system). It is basically divided into the western, central and eastern sectors. The western sector consists of the Küda-Subashi suture zone, the Mazar-Kangxiwar suture and the central West Kunlun microblock. The central sector covers the following five suture zones: the Altun, North Qilian, Qaidam northern marginal, Qimantag-Wutuo and East Kunlun southern marginal sutures, in addition to some microblocks such as the mid-south Qilian, Qaidam, Ayakkum and Maqen microblocks. The eastern sector is composed of the Shangdan suture zone, Mianlüe suture zone and central Qinling-Dabie microblock. The KQQ suture system experienced (1) extending-rifting of the Rodinia super-continent in the early-middle Sinian (～780–600 Ma); (2) the formation and evolution of the KQQ archipelagic ocean during the Late Sinian-Ordovician (～600–440 Ma), and (3) closing of the KQQ ocean and forming of the KQQ suture system during the Late Ordovician—early Silurian (～440–400 Ma). As a system comprising many suture zones and microblocks, the KQQ suture system constitutes the foundation of the Central Orogenic Belt of china.

关键词： A Study of the Kunlun-Qilian-Qinling Suture System

General regularity of dynamic responses of slopes under dynamic input

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science china(Technological sciences) 2003年第Z1期46卷 120-132页

作者： QI Shengwen, WU Faquan & SUN Jinzhong institute of geology and geophysics, chinese academy of sciences, beijing 100029, china College of Engineering Technique, china University of Geosciences, beijing 100083, china chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China china Univ Geosci Coll Engn Techn Beijing 100083 Peoples R China

Through lots of numerical simulations with FLAC3D, dynamic responses of slopes are comprehensively studied in this paper and the general regularities of the isoline of the coefficient of the displacement, velocity and acceleration of the slope section are reached. Given a certain material slope, if the height of the slope is less than a certain value, the displacement, velocity and acceleration linearly enlarge with elevation in the vertical direction; if the height of the slope surpasses the certain value, the displacement,velocity and acceleration do not linearly enlarge with elevation any more, on the other hand, they fluctuate with a certain rhythm. At the same time, the rhythm appears in the horizontal direction, and the displacement, velocity and acceleration of the slope surface enlarge near the slope surface. The distribution form of the isoline of the coefficient of displacement, velocity and acceleration in the section of the slope is remarkably affected by the slope angle. In the certain area near the slope surface, the isoline of displacement,velocity and acceleration is parallel to the surface of the slope; in the mean time the strike direction of the extremum area is parallel to the surface of the slope, too. The charts of the slope dynamic responses can be depicted with two indexes, one is the strike direction of the isoline, and the other is the number of the rhythm extremum area of the direction parallel to the surface of the slope.

关键词： slope, dynamic response, regularity, rhythm.

Principles and methods of quantitative analysis on b-axis disorder in 2 : 1 dioctahedral phyllosilicate

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chinese science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese academy of sciences, Changsha 410013, china 2. institute of geology, chinese academy of sciences, beijing 100029, china Changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3n) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3n) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.

Ambient noise near the sea-route

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science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2, LI ZhengLin1,3 & PENG ZhaoHui1 1 National Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, beijing 100190, china 2 institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 3 NanHai Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Haikou 570206, china National Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

DMTB:A comprehensive online resource of 16S rRNA genes,ecological metadata,oligonucleotides,and magnetic properties of magnetotactic bacteria

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chinese science Bulletin 2011年第6期56卷 476-478页

作者： LIN Wei1,2, LI Bi1,2 & PAN YongXin1,2 1 Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth’s Deep Interior, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2 France-china Bio-Mineralization and Nano-Structures Laboratory, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china Paleomagnetism and Geochronology Laboratory Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China France-china Bio-Mineralization and Nano-Structures Laboratory Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Magnetotactic bacteria (MTB) are of interest in microbiology, biomineralization, advanced magnetic materials, and bio-geo-sciences because of their ability to form highly ordered intracellular magnetic minerals. Great strides for MTB studies have been made in the past four decades. In this paper we complied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It contains information of 16S rRNA gene sequences, corresponding ecological metadata, oligonucleotides, and magnetic properties of MTB. The comprehensive information contained in DMTB will provide a very useful data resource for researchers from different disciplines. The website of DMTB is at http://***/.

关键词： rRNA基因序列趋磁细菌 16S 网上资源寡核苷酸磁学性质生态磁性材料

MOLECULAR DYNAMICS SIMULATIONS OF FILLED AND EMPTY CAGE-LIKE WATER CLUSTERS IN LIQUID WATER AND THEIR SIGNIFICANCE TO GAS HYDRATE FORMATION MECHANISMS

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化工学报 2003年第Z1期54卷 62-66页

作者： GUO Guangjun,ZHANG Yigang and ZHAO Yajuan institute of geology and geophysics,chinese academy of sciences beijing 100029,chinese institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Molecular dynamics simulations are performed to observe the evolutions of 512 and 51262 cage-like water clusters filled with or without a methane molecule immersed in bulk liquid water at 250 K and 230 K. The lifetimes of these clusters are calculated according to their Lindemann index δ (t) using the criteria of δ≥0.07. For both the filled and empty clusters, we find the dynamics of bulk water determines the lifetimes of cage-like water clusters, and that the lifetime of 512 62 cage-like cluster is the same as that of 512 cage-like cluster. Although the methane molecule indeed makes the filled cage-like cluster more stable than the empty one, the empty cage-like cluster still has chance to be long-lived compared with the filled clusters. These observations support the labile cluster hypothesis on the formation mechanisms of gas hydrates.

关键词： like in time that were MOLECULAR DYNAMICS SIMULATIONS OF FILLED AND EMPTY CAGE-LIKE WATER CLUSTERS IN LIQUID WATER AND THEIR SIGNIFICANCE TO GAS HYDRATE FORMATION MECHANISMS of cage GAS

Garnet Sm-Nd and U-Pb systems: A case study of a granulite from the European Variscan belt

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chinese science Bulletin 2002年第15期47卷 1284-1288页

作者： CHEN FukunInstitut fur Mineralogie, Petrologie und Geochemie, Universitat Tubingen, 72074 Tubingen, Germany institute of geology and geophysics, chinese academy of sciences, beijing 100029, china Institut für Mineralogie Petrologie und Geochemie Universität Tübingen Tübingen Germany institute of geology and geophysics Chinese Academy of Sciences Beijing China

This study presents zircon and garnet ages of a mafic granulite from the high-grade Variscan basement of the Black Forest, Germany and discuss isotope closure temperature of garnet Sm-Nd and U-Pb systems. Zircon grains yield 207Pb/206Pb ages between -340 and -414 Ma by the U-Pb and evaporation methods. In contract, garnet dating gives Sm-Nd and Pb-Pb isochron ages of (398±3) Ma and (411±14) Ma, respectively, which are older than most of zircon ages. These data imply that most of zircons lost radiogenic Pb, probably due to metamictization or recrystallisa-tion during the granulite-facies metamorphism (-800°C) at -340 Ma. Garnet Sm-Nd and U-Pb systems preserve chronological information of pro-grade metamorphism, probably profiting from a fluid-absence metamorphic environment. These results demonstrate that garnet mineral can be a better candidate than zircon mineral to date high-grade metamorphism by the U-Pb and Sm-Nd methods in some cases.

关键词： Variscan granulite garnet Sm-Nd U-Pb.

Searching for the remains of subducted continental slabs

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chinese science Bulletin 2000年第5期45卷 385-386页

作者： LIU Guangdinginstitute of geology and geophysics, chinese academy of sciences, beijing 100101, china institute of geology and geophysics Chinese Academy of Sciences Beijing China

On the basis of oceanic geological and geophysical observations the global plate tectonics theory wasput forward in the late 1960s. It inherited the essence of mobilism of continental drift and sea-floorspreading, caused a revolution of earth sciences in the twentieth century. But plate tectonics cannotsatisfactorily explain the complicated geological phenomena of continents, it fails in elucidating

关键词： Searching for the remains of subducted continental slabs der Nature

The features of gravity field and deep structure in western part of the South Yellow Sea

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chinese science Bulletin 2000年第8期45卷 759-764页

作者： WANG Qianshen1 & AN Yulin1. institute of geophysics, chinese academy of sciences, beijing 100101, china 2. chinese University of geology, beijing 100083, china institute of geophysics Chinesc Academy of Sciences Beijing China chinese University of geology Beijing China

The gravity data from the sea region to the west of 124° E of the South Yellow Sea have been processed and the feature of gravity fields analyzed. An experience relationship formula on the filter wavelength and corresponding depth has been put forward. Combined with the geological and seismic data, the deep tectonic framework and structural characters as well as possible favourable prospecting district for hydrocarbon in the South Yellow Sea have been discussed and analyzed.

关键词： western part of the South Yellow Sea gravity field deep structure.