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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science China Earth sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, li Jiliang1, liU Yifeng1 & liU Zhenkuan4 1. institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 2. institute of geophysics, China Seismological Bureau, beijing 100085, China 3. institute of Deposition Resource, chinese academy of Geosciences, beijing 100037, China 4. School of Exploration and Information, China university of Geosciences, beijing 100083, China institute of geology and geophysics Chinese Academy of Sciences Beijing China institute of geophysics China Seismological Bureau Beijing China institute of Deposition Resource Chinese Academy of Geosciences Beijing China School of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, China. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we reco.- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho disco.tinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho disco.tinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the co.tact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

The Topological Analysis of Minerals

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The Topological Analysis of Minerals

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest China:Evidence from sandstone detrital and geochemical reco.ds

亚洲晶体学联合大会

作者： li jia-ju1 li hui2 1 institute of geology and geophysics chinese academy of sciences beijing 10002. 1 shimadzu international trading(Shanghai) co. limited beijing branch 10002. 2 beijing university of technology beijing 100124

＜正＞The electron density distribution of Pyrite and Pyrrhotite were reco.structed with powder X-ray diffraction data in this research work. Meanwhile, the gradient of charge density and its Laplacian were also suppl...

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Science China Earth sciences 2005年第9期48卷 1387-1402页

作者： li Zhong1, GUO Hong2, WANG Daoxuan3 & liN Wei1 1. institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 2. Tarim Oilfield branch, CNPC, Korla 841000, China 3. Hefei university of Industry, Tunxilu 193, Hefei 230009, China institute of geology and geophysics Chinese Academy of Sciences Beijing Chin Tarim Oilfield branch CNPC Korla China Hefei university of Industry Hefei Chin

Similar to co.positional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest China, major element analysis of whole sandstones from the same profiles shows four disco.tinuous depositional interfaces or periods, respectively co.responding to Lower Triassic\Middle Triassic, Upper jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1) From the first to fifth phase, a depositional suite changes from maroon and co.rse clastic, through grey-dark grey and fine, red and co.rse, red-mottled, interlayered by gypsum, to brown and co.rse clastic assemblages, acco.panying detrital co.ponent evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and co.plex detritus gradually dominate in sandstones in post-Late jurassic, with rapid reduction of co.positional maturity. (2) For major element geo- chemical parameters of whole sandstones, CaO and Fe2 O * 3+MgO co.tents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late jurassic. (3) co.tra some aggregative indicators for weathering indexes of sandstone detrital co.ponent, Al2O3/(CaO+Na2O) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late jurassic. It is found that sandstone samples of the first, seco.d and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important disco.tinuous depositional interface reco.ding paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional reco.d, tectonic transition, Mesozoic-Cenozoic.

Vermiform trace fossils from the Precambrian Ruyang Group, western Henan

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chinese Science Bulletin 1997年第3期42卷 251-254页

作者： HU jianmin, MENG Qingren and li Wenhou1 Xi’ an co.lege of geology, Xi’an 710054, China 2. institute of geophysics, chinese academy of sciences, beijing 100101, China 3 Department of geology, Northwest university, Xi’an 710069, China Xi’an co.lege of geology Xi’an China institute of geophysics Chinese Academy of Sciences Beijing China Department of geology Northwest University Xi’an China

THE origin and evolution of Precambrian lives has been a long-standing co.troversial problem. It is now generally accepted by most paleontologists that the origin of metazoa can be traced back to more than 1000 Ma, because the Ediacara and latest pre-Ediacara fauna, such as the Huainan fauna, are featured by their diversification of forms, co.plicated structures

关键词： Precambrian trace fossil Ruyang Group.

Crust and uppermost mantle structure of the Ailaoshan-Red River fault from receiver function analysis

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Science China Earth sciences 2006年第10期49卷 1043-1052页

作者： XU Mingjie1, WANG liangshu1, liU jianhua2, ZHONG Kai1, li Hua1, HU Dezhao1 & XU Zhen1 1. Department of Earth sciences, Nanjing university, Nanjing 210093, China 2. institute of geology and geophysics, chinese academy of sciences, beijing 10002., China Department of Earth sciences Nanjing University Nanjing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

S-wave velocity structure beneath the Ailaoshan-Red River fault was obtained from receiver functions by using teleseismic body wave reco.ds of broadband digital seismic stations. The average crustal thickness, Vp/Vs ratio and Poisson’s ratio were also estimated. The results indicate that the interface of crust and mantle beneath the Ailaoshan-Red River fault is not a sharp velocity disco.tinuity but a characteristic transition zone. The velocity increases relatively fast at the depth of Moho and then increases slowly in the uppermost mantle. The average crustal thickness across the fault is 36―37 km on the southwest side and 40―42 km on the northeast side, indicating that the fault cuts the crust. The relatively high Poisson’s ratio (0.26―0.28) of the crust implies a high co.tent of mafic materials in the lower crust. Moreover, the lower crust with low velocity co.ld be an ideal position for deco.pling between the crust and upper mantle.

关键词： receiver function, Ailaoshan-Red River fault, velocity structure, Poisson's ratio, crust and upper mantle.

CALCISPONGES AND HYDROZOANS FROM PERMIAN REEFS IN WESTERN GUANGXI

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古生物学报 2002年第3期 343-348页

作者： FAN jia Song 1) , WANG Yu Mao 2) , and WU Ya Sheng 1) 1) institute of geology and geophysics, the chinese academy of sciences, beijing 10002. 2) The seco.d geological team, Guangxi Bureau of geology and Mineral Resources, Nanning 53000

ＳｕｍｍａｒｙＴｈｅｐｒｅｓｅｎｔｐａｐｅｒｄｅｓｃｒｉｂｅｓｂｒｉｅｆｌｙｓｏｍｅｇｅｎｅｒａｌｆｅａｔｕｒｅｓｏｆｔｈｅＰｅｒｍｉａｎｒｅｅｆｓｅｘｐｏｓｅｄｉｎＴｉａｎｌｉｎ ,ＬｉｎｇｙｕｎａｎｄＦｅｎｇｓｈａ... 详细信息

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关键词： Sphinctozoan Inozoan Hydrozoan reefs Permian Guangxi ChinaSummary The present paper describes briefly some general features of the Permian reefs exposed in Tianlin lingyun and Fengshan co.nties where abundant framebuilding org

DMTB:A co.prehensive online resource of 16S rRNA genes,eco.ogical 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 10002., China 2 France-China Bio-Mineralization and Nano-Structures Laboratory, institute of geology and geophysics, chinese academy of sciences, beijing 10002., 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 co.plied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It co.tains information of 16S rRNA gene sequences, co.responding eco.ogical metadata, oligonucleotides, and magnetic properties of MTB. The co.prehensive information co.tained 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

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science China Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, li Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075 China 2. Qinghai institute of Salt Lakes, chinese academy of sciences. Xining 810008, China 3. institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 4. Department of Geography, Qinghai Normal university, Xining 810008, China State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of geology and geophysics Chinese Academy of Sciences Beijing China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China Department of Geography Qinghai Normal University Xining China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which co.sist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reco.struction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic co.relation suggest that terraces of Tll, T10, T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological reco.d, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

Chronological reco.d of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zirco.s in the Late Mesozoic andesite from Western liaoning

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Progress in Natural Science:Materials international 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 liu Xiaoming~3 li Zhitong~4 (1.School of Earth and Space sciences,Peking university,beijing 100871,China 2.institute of geology and geophysics and Key Laboratory of Mineral Resources,chinese academy of sciences,beijing 10002.,China 3.Key Laboratory of co.tinental Dynamics,Northwestern university,Xi'an 710069,China 4.institute of geology and Mineral Resources of Shenyang,Shenyang 110032,China) School of Earth and Space sciences Peking University Beijing 100871 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Acad. of Sci. Beijing 100029 China Key Laboratory of co.tinental Dynamics Northwestern University Xi'an 710069 China institute of geology and Mineral Resources of Shenyang Shenyang 110032 China

Cathodoluminescence spectrosco.ic analysis of zirco.s in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western liaoning reveals zoning structures of the zirco.s in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zirco.s is remnant zirco. with a U-Pb dating of 254 Ma,which is co.sistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zirco. crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly co.sistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North China Mesozoic volcanic rock U-Pb chronometry of zirco. underplating granulite