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A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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Science China Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3.4, ZHANG Hucai2. WANG Weiguo3.& AN Chenbang3.1. Nanjing institute of geology and Palaeontology,{2., Nanjing 2.0008, China 2. Nanjng institute of Geography and Limnology,{2., Nanjing 2.0008, China 3. Environment and Resources College, Lanzhou University, Lanzhou 73.000, China 4. beijing Normal University, beijing 100875, China 1. Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. beijing Normal University Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2.0}ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science China(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2.REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of Opto-Electronics,{2. academy of {3.,beijing 100190,China 2.Graduate University of chinese academy of sciences,beijing 100049,China 3.Lanzhou institute of Chemical Physics,{2. academy of {3.,Lanzhou 73.000,China 1. academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of China,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. institute of Engineering Thermophysics, chinese academy of sciences, {2. 100080, China 2. Graduate School, chinese academy of sciences, {2. 100080, China 1. institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science China Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth sciences and Natural Resources, China University of Geosciences, {2. 100083. China 2. Faculty of Earth sciences, China University of Geosciences, Wuhan 43.074, China 3. {2. SHRIMP Center, institute of geology, {12. academy of Geological sciences, {2. 10003., China 1. Faculty of Earth sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China 3. beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Plumb line variation at Tangshan during 1987―1998 and its relation with the earthquakes around

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Science China Earth sciences 2009年第1期52卷 101-107页

作者： LI ZhengXin1,2.& LI Hui3.1 Shanghai Observatory,chinese {2. of {2.,Shanghai 2.003.,China 2.{3. of Geodesy and geophysics,chinese {2. of {2.,Wuchang 43.077,China 3.{3. of Seismology,China Earthquake Administration,Wuchang 43.071,China Shanghai Observatory Chinese Academy of Sciences Shanghai 200030 China institute of Geodesy and geophysics Chinese Academy of Sciences Wuchang 430077 China institute of Seismology China Earthquake Administration Wuchang 430071 Chin

Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the beijing-Tangshan *** has been found that PLV at Tangshan are related with the 3. earthquakes in this *** appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.

关键词： plumb line variations network in northern China variations of local gravity field earthquakes

Mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating

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Science China Earth sciences 2005年第2期48卷 192-198页

作者： WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4 & CHEN Yuchuan institute of Mineral Resources, chinese {2. of Geological {3., beijing 10003., China National Center of Rock and Mineral Analysis, chinese {2. of Geological {3., beijing 10003., China Resource Assessment Center of Yunnan, Kunming 650011, China institute of {12. and geophysics, chinese academy of sciences, beijing 100101, China chinese {2. of Geological {3., beijing 10003., China 1. institute of Mineral Resources Chinese Academy of Geological Sciences 100037 Beijing China 2. National Center of Rock and Mineral Analysis Chinese Academy of Geological Sciences 100037 Beijing China 3. Resource Assessment Center of Yunnan 650011 Kunming China 4. institute of geology and {2. Chinese Academy of Sciences 100101 Beijing China 5. chinese academy of Geological {2. 100037 Beijing China

Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 3..9±1.1 Ma for the Machangqing deposit and 3..4±0.5 Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (3..4 Ma, 3..9 Ma, 3..2.Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene.

关键词： Re-Os isotopic dating, porphyry Cu deposits, Cenozoic, mineralization episode.

δ^13.sc values of the loess-paleosol sequence in Dali area, Shaanxi Province, China, and paleoenvironmental implications

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chinese Science Bulletin 2003年第9期48卷 902-907页

作者： LI Yumei & LIU Dongsheng (LIU Tungsheng)institute of geology and {2.,{3., beijing 10002. (e-mail: liyrney@***) 1. institute of geology and {2. Chinese Academy of Sciences Beijing 100029

The carbon isotopic ratios of carbonate in the two profiles of the Dali area were analyzed and some new understandings on the influencing factors of the δ13.SC value of the loess-paleosol sequence and its paleoenvironmental implications were discussed preliminarily in this report. The 13.SC value of the Dali loess-paleosol sequence is synchronizing with the variance of magnetic susceptibility basically and the negative peaks of the δ13.SC curves are corresponding to the different developmental periods of the paleosol. It is believed that the intervention of the CO2.produced by plants will cause the decrease of the δ13.SC value, the amplitude of which may be relevant to the paleovegetation density and the ancient humidity. The relative biomass of C4 plants in the vegetation will affect the sublevel change of the δ13.SC. Low δ13.SC value by and large indicates the environmental conditions of the relatively abundant vegetation and humid climate. During the last 2.0000 years, the period with the sparsest vegetation and the most arid climate is the phase of the loess in L2.depositing and the period with the most abundant vegetation and the most humid climate is the last interglacial period. The δ13.SC curves of Dali also show that the High Temperature and Large Precipitation Event of the Qinghai-Tibetan Plateau during 40-3. kaBP had affected the Central Shaanxi Plain with relatively humid climate, and had apparent influence on the local vegetation and humidity.

关键词：古环境大理地区黄土陕西湿润气候碳同位素植被高温天气

Orogen-parallel extension in Himalaya: Is it the indicator of collapse or the product in process of compressive uplift?

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chinese Science Bulletin 2000年第2期45卷 114-120页

作者： ZHANG Jinjiang, DING Lin, ZHONG Dalai & ZHOU Yong institute of geology and {2..{3.. beijing 10002., China institute of geology and {2. Chinese Academy of Sciences Beijing China

Extensional structures developed extensively in Himalaya with their strikes perpendicular to that of the orogenic belt. The studies of such structures in Qusum, Burang, Lhozhag, Nyalam and Yadong show that they represent an orogen-parallel extension. The basins produced by the extension experienced orokyn-perpendicular compression during their formation. The ages of the extension rang from 16 to 13.Ma and coincide with the intensive compressive stage in Southeastern Asia. Therefore, the extension is Syn-shortening and the dominate tectonic movement in Himalaya was compression and uplift during the extension. The extension was the partition of compressive deformation rather than the indicator for the collapse and falling of the Tibetan Plateau.

关键词： Himalayan orognic helt syn-shortening extension uplift

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 {2.,{3., beijing 10002. Science Press,{3., beijing 100717 institute of geology and {2. Chinese Academy of Sciences Beijing 100029 Science Press Chinese Academy of Sciences Beijing 100717 [?]3.ian Qiantao Born in 1945 graduated from the Department of geology South-Central University of Technology in 1970 and obtained his master's degree and doctor's degree at the Graduate School and the Institute of Geology Chinese Academy of Sciences in 1981 and 1987 respectively. He is currently a professor of the Institute of Geology and Geophysics Chinese Academy of Sciences and has long been engaged in the research of tectonics petrology mineral deposits and geochemistry. Tel: (010) 62008058 E-mail: bianqt@***

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