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Science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2, 3 & YANG Nong1 1. institute of Geomechanics, chinese academy of Geological sciences, beijing 100081, china 2. institute of geology, chinese academy of Geological sciences, beijing 100037, china 3. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 350℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/39Ar dating, late Cenozoic.

“Tali Glaciation” on Massif Diancang

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Science china Earth sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3 & YANG LiRong3 1 institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, china 2 College of Environmental sciences, Peking University, beijing 100871, china 3 institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 1. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. College of Environmental sciences Peking University Beijing 100871 China 3. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 30—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3600 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming31. South china Sea institute of Oceanology, chinese academy of sciences. Guangzhou 510301, china 2. State Key Laboratory of Loess and Quaternary geology, Earth Environmental institute, chinese academy of sciences, Xi’an 710075, china 3. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia

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Science china Earth sciences 2005年第7期48卷 1025-1039页

作者： HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3 & HUANG Fengbao1 1. Nanjing institute of geology and Paleontology,chinese academy of sciences,Nanjing 210008,china 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. institute of geology and geophysics,chinese academy of sciences,beijing 100029,china Nanjing institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of geology and Geoohysics Chinese Academy of Sciences Beijina 100029 China

Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4200?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration.

关键词： phytolith and pollen records grassland environment change human impact Holocene central eastern Inner Mongolia.

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 100029, china 4. Department of Geography, Qinghai Normal University, Xining 810008, china chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R 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 consist 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 reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation 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 record, 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.

Rainfall-induced landslide stability analysis in response to transient pore pressure——A case study of natural terrain landslide in Hong Kong

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Science china(Technological sciences) 2003年第z1期46卷 52-68页

作者： LAN Hengxing, ZHOU Chenghu C. F. LeeWANG Sijing & WU Faquan State Key Laboratory of Natural Resources and Environmental System, institute of Geographical Sci-ences and Natural Resources Research, chinese academy of sciences, beijing 100101, china Department of Civil Engineering, Hong Kong University, Hong Kong, china 3. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china chinese Acad Sci State Key Lab Nat Resources & Environm Syst Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Univ Hong Kong Dept Civil Engn Hong Kong Hong Kong Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.

关键词： rainfall-induced landslide, transient pore pressure, landslide stability in response to rainfall, GIS.

Paleotemperature changes over the past 3000 years in eastern beijing, china: A reconstraction based on Mg/Sr records in a stalagmite

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chinese Science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2, XIA Ming1, KU Tehlung2, PENG Zicheng3, CHEN Yushu4 & ZHANG Zhaofeng3 1. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. Department of Earth sciences, University of Southern California, Los Angeles, CA90089-0740, USA 3. Department of Earth and Space Science, University of Science and Technology of china, Hefei 230026, china 4. beijing Foshan Tourist Service Centre, beijing 101201, china institute of geology and geophysics. chinese academy of sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern beijing over the past 3000 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3000—2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500—200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3000年

India Collided with Asia at Least 72 Ma:Recognition of An Underfilled Foreland Basin in Central Himalaya

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地学前缘 2009年第S1期16卷 271-272页

作者： Xiumian Hu,Jiangang Wang,Luba Jansa,Fuyuan Wu,Jinhai Yu 1.Department of Earth sciences,Nanjing University,Nanjing 210093,china. 2.Geological Survey of Canada-Atlantic,Dartmouth,N.S.,Canada 3.institute of geology and geophysics,chinese academy of sciences beijing 100029,china

The Himalayan peripheral foreland basin developed when India and Asia *** studies in the Himalayan foreland were mostly concentrated on Neogene continental clastic sedimentation in sub-Himalaya or Paleogene shallow ma... 详细信息

关键词： Himalayan foreland underfilled foreland basin peripheral foreland

Experimental study on the P wave velocity in rocks from lower crust and crust-mantle transitional zone beneath the Hannuoba

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Experimental study on the P wave velocity in rocks from lowe...

Climatological analysis and modeling of the ionospheric global electron content

中国科学院地质与地球物理研究所2003学术年会

作者： FAN Qicheng~(1,2**),SUI Jianli~(1,2),ZHANG Hongfu~1,ZHAI Mingguo~1 and XIE Hongsen~3 (1.institute of geology and geophysics,chinese academy of sciences,beijing 100029,china 2.institute of geology,china Seismological Bureau,beijing 100029,china 3.institute of Geochemistry,chinese academy of sciences,Guiyang 550002,china)

Cenozoic basalt-borne mafic granulite-facies plagioclase pyroxenite and eclogite-facies garnet pyroxenite xenoliths from the Hannuoba,as well as nearby Archean terrain granulites,are selected for the experimental study on the P wave velocity at high temperature and high pressure in order to reveal the present-day compositional features(or the lower crust and crust-mantle transitional *** show that mafic xenoliths have high V(7.0～8.0 km/s),in contrast,the Archean terrain granulites have low V(<7.0 km/s). High V mafic xenoliths can represent the present-day compositional features for the lower crust and crust-mantle transitional zone beneath the *** provides new evidence for the crust vertical growth and the formation of the crust-mantle transitional zone resulting from the magma *** V Archean granulite still remains the characteristics of the early lower crust.

关键词： lower crust and crust-mantle transitional zone mafic xenollth wave velocity Hannuoba

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Climatological analysis and modeling of the ionospheric glob...