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chinese Science Bulletin 2004年第24期49卷 2613-2619页

作者： SHANG Qinghua Nanjing institute of geology and Paleontology,chinese academy of {4.,Nanjing 210008,China institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of {4.,beijing 10004.,China Nanjing institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Zhesi (Jisu) Formation of the Middle Per- mian in Nei Mongol (Inner Mongolia) was commonly con- sidered to be a shallow marine sequence. Here I report the radiolarians found in the argillite bed of that formation in Zhesi and Xilinhot areas. This fact indicates a deep marine sedimentary facies persisted during the Middle Permian, and suggests that the ocean between the North China Block and Siberian Craton was not closed until the Late Guadalupian. The suture of this two blocks is probably extends along the Linxi ophiolite belt, south of the Hegenshan ophiolite belt.

关键词：造山带地质意义内蒙古放射虫二叠纪

LATE QUATERNARY VARIATION OF THE ARIDITY INDEX IN THE BADAIN JARAN DESERT,INNER MONGOLIA,CHINA─A DEDUCTION FROM LANDSCAPE EVOLUTIONS

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Scientia Geologica Sinica 2000年第2期 205-214页

作者： YANG Xiaoping (institute of geology and geophysics, chinese academy of sciences{4.)

Palaeoclitalologists have faced for decades the challenge to obtain quantitative palaeoclimatic parameters for the arid and semiarid environrnent The landscape conception in the sense of climatic geomorphology can be used to bridge this gap. In the Badain Jaran Desert, geomorphological studies show that there are clear evidences for the shifting of morphodyndric zones. Comparing the former and present-day formation of landscapes indicates that the precipitation during the less arid periods was much larger than that of previously thought. This is confirmed by lake level changes both in the dune fields and in the marinal regions. Decreased aridity indexes of ca. 30 ka B.P. and 20 ka B.P. signal that the influence of westerlies on the arid region of northwestem China was presumably intensified at these times

关键词： der Wang A DEDUCTION FROM LANDSCAPE EVOLUTIONS LATE QUATERNARY VARIATION OF THE ARIDITY INDEX IN THE BADAIN JARAN DESERT,INNER MONGOLIA,CHINA

Evolutionary Stages of the Earliest Skeletal Fauna and Division and Correlation of the Precambrian-Cambrian Boundary Strata

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Acta Geologica Sinica(English Edition) 1988年第3期1卷 233-248+349页

作者： Yue Zhao institute of geology, chinese academy of Geological {4., beijing institute of geology Chinese Academy of Geological Sciences Beijing

Through an analysis of the earliest fossils in the Precambrian-Cambrian boundary beds in various parts ofthe world, especially in the Yangtze and Siberia platforms, the author has found that the evolution of the ea-rliest skeletal animals may be divided from older to younger into three stages. The first stage (theAnabarites-Protohertzina fauna) is represented by the Anabarites-Protohertzina zone of the Meishucunian Stagein the Yangtze platform and the A. trisulcatus and P. cristata zones of the Manykayn Stage in Siberia. The sec-ond stage (the earliest orthothecimorphid and mollusc fauna) is represented by the Paragloborilus-Siphogonuchites zone of the Meishucunian Stage and the Aldanocyathus sunnaginicus zone of the TommotianStage. The third stage (the earliest hyolithimorphid and lapworthellid fauna) is represented by the Sinosachiteszone of the Meishucunian Stage and the *** and *** zones of the Tommotian Stage. The threeevolutionary stages can be used as a criterion for worldwide correlation.

关键词： Evolutionary Stages of the Earliest Skeletal Fauna and Division and Correlation of the Precambrian-Cambrian Boundary Strata

Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic

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chinese Science Bulletin 2003年第13期48卷 1375-1380页

作者： ZHANG Tonggang, CHU Xuelei, ZHANG Qirui, FENG Lianjun & HUO Weiguo Key Lab of Mineral Resources Exploration and Research, institute of geology and geophysics, chinese academy of sciences,{4., China Key Lab of Mineral Resources Exploration and Research Institute of Geology and Geophysics Chinese Academy of Sciences China

Successive analyses of sulfur and carbon isotopic compositions of carbonates strata in the Doushantuo Formation in the Yangtze area were accomplished through a method of extracting trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were estimated from the samples that show the least diagenetic alteration. A high-resolution age curve of sulfur isotopes in seawater sulfates was obtained in the Doushantuo stage, which reflects the trend of variation in seawater sulfur isotopes after the Neoproterozoic snowball Earth event. Similar characteristics of variation in carbon isotopes were observed in the coeval carbonates. A large positive d 34. excursion over +20?occurs in ancient seawater sulfates in the early Doushantuo stage. Simultaneously, the d 13C values in ancient seawater carbonates exhibit a positive excursion up to 10. The maximum d 34. and d 13C values are +4..4.and +6.9? respectively. In the middle Doushantuo stage, the range of variation in d 34. values of seawater is relatively narrow, but d 13C values are quite high. Then, d 34. values of seawater become oscillating, and the same occurs in d 13C values. Negative excursions in d 34. and d 13C values occur simultaneously at the end of the Doushantuo stage, and the minimum d 34. and d 13C values dropped down to -10.1 and -5.7? respectively. The characteristics of variations in the sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment that became beneficial to inhabitation and propagation of organism. The organic productivity and burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable after the global glaciation. The global climate and environment possibly were fluctuating and reiterating. The negative excursions in d 34. and d 13C values occurring at the end of the Doushantuo stage may represent a global event, which might be related to oxidation of dee

关键词：硫碳同位素分馏新元古代成岩作用

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 {4.,Nanjing 210008,China 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. institute of geology and geophysics,chinese academy of {4.,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 4.00?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.

RECENT ADVANCES IN SPACE STUDIES OF THE EATRH SURFACE, METEOROLOGY AND CLIMAfE IN CHINA

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空间科学学报 1998年第S1期18卷 61-70页

作者： LU Da-ren(institute of Atmospheric Physics, The chinese academy of sciences, beijing 100029)

During past 2 years, chinese scientists have conducted a series of scientific,technical, and application research relating to earth observation for satellite and payload development, meteorological and environmental monitoring, disaster reduction, resources surveying, and sustainable development of national economy and society. An short and incomplete review is given in this paper.

关键词： chinese space research Earth observation Satellite programs Remote sensing

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,{4., China 2 Wuhan institute of Physics and Mathematics, chinese academy of sciences, Wuhan 4.0071, China 3 Graduate University, chinese academy of sciences, beijing 10004., China 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, chinese academy of sciences) 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

Fluid differentiation and gold mineralization

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chinese Science Bulletin 1999年第S2期44卷 13-15页

作者： QIN Dajun, CAI Xinping and XU Xingwang institute of geology, chinese academy of sciences, beijing 100029, China institute of geology Chinese Academy of Sciences Beijing 100029 China

GOLD mineralization is closely related to ore-forming fluids. During the evolution of fluids, their naturescontinuously change, and the differentiation of the fluids dominates these changes. Fluid differentiationincludes fluid from melt, fluid immiscibility, gasseparating from fluids and so on. We can understand fluids through inclusions, stable isotope andore-forming experiments. Under the poststage reformation, the composition and phases of inclusionsmight be changed, hence, the initial forming conditions of fluids are difficult to be defined onlythrough the observation of these inclusions. Theexistence of solution phase, gas phase and solidphase (fig. 1) indicate that differentiation

关键词： fluid differentiation gold mineralization.

CENOZOIC COLLISIONAL DEFORMATION AND LITHOSPHERE TECTONIC EVOLUTION OF THE EASTERN HIMALAYAN SYNTAXIS

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地学前缘 2000年第S1期7卷 12-13页

作者： Ding Lin, Zhong Dalai, Zhang Jinjiang, Ji Jianqing(institute of geology and geophysics, chinese academy of sciences,{4.,China)

The Eastern Himalayan Syntaxis (EHS) is one of the strongest deformation area along the Himalayan belt resulted from the collision between Indian plate and the Eurasian plate since 50～60Ma, and has sensitivity tracked and preserved the whole collisional processes. It should depend on the detail geological investigations to establish the deformational accommodate mode, and the uplift history, to elucidate the deep structure and the crust\|mantle interaction of the EHS. The Namjabarwa metamorphic complex indented into the Gangdise arc along the sinistral Pai shear fault and the dextral Aniqiao shear fault on the both sides of the Great Canyon of Yalung Zangbo river since the collision of the NE corner of the Indian plate and the Eurasian Plate at 60～70Ma [1] . The distance between Yarlung Zangbo suture and Bangong—Nujiang suture is shortened more 120km in the EHS area than that of the Lhasa block.

关键词： Eastern Himalayan Syntaxis collisional deformation Magmatism and high\|pressure metamorphism Lithospheric evolution

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science China Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2, WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3 1. State Key Laboratory of Marine geology, Tongji University, Shanghai 200092, China 2. institute of geology and geophysics,{4., beijing 100029, China 3. institute of Botany,{4., beijing 100093, China State Key Laboratory of Marine geology Tongji University Shanghai China institute of geology and geophysics chinese academy of sciences {4. China institute of Botany chinese academy of sciences beijing China

The deep sea records from the ODP Sites 114. and 114. in the northern and southern South China Sea (SCS), including foraminiferal δ 18O and δ 13C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 4. ka and 23 ka cycles. Although G. ruber δ 13C of Site 114. is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South China Sea.

关键词： South China Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.