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Natural and anthropogenic impacts on the Asian monsoon precipitation during the 20th century

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Natural and anthropogenic impacts on the Asian monsoon preci...

An environmental database and temporal and spatial distribution of chinese paleoanthropologieal sites

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ZHOU Xin~(1,2),GUO ZhengTang~(1*) & QIN Li~(1,2,3) 1 key laboratory of cenozoic geology and environment,institute of geology and geophysics,chinese academy of sciences, beijing 100029,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Chongqing Three Gorges institute of Paleoanthropology,china Three Gorges Museum,Chongqing 400015,china

The increase in the global average temperature during the last century is considered an integrated result of anthropogenic and natural forcing,but different views remain about the anthropogenic impacts on the Asian monsoon *** on the～2000-year records of stalagmiteδO from the Dongge Cave(Guizhou Province) and Wanxiang Cave(Gansu Province),we address the possible anthropogenic impacts on the southwest and southeast Asian monsoon from 1900-2000 AD,using the method of Singular Spectrum Analysis(SSA).The results show that the monsoon precipitation trends in the last 100 years at both sites can be obtained through SSA prediction using the data prior to 1900 *** suggest that human activity has not significantly affected the trends of monsoon precipitation despite of its impact on the global temperature.

关键词： global warming Asian monsoon Singular Spectrum Analysis(SSA) stalagmiteδ18O

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An environmental database and temporal and spatial distribut...

Quantitative assessment of the complexity of geological structures in terms of seismic propagators

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： WU ChunLin~(1,2),ZHANG Yan~1,LI Qin~1,GUO ZhengTang~(1*) & GAO Xing~3 1 key laboratory of cenozoic geology and environment,institute of geology and geophysics,chinese academy of sciences,beijing 100029, china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 laboratory of Human Evolution,institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044, china

A comprehensive database of paleoenvironmental settings for paleoanthropological sites provides a useful tool to explore the link between human evolution and paleoenvironmental changes.A preliminary GIS-based environmental database for paleoanthropological sites in china(EDPC) was constructed based on data collected from published *** database currently contains 1114 paleoanthropological *** will be available for online access following the establishment of relevant rules,and after improvement and further development through regular and sustained updates by internal and external *** analyses using the GIS system yielded new evidence regarding human-environmental relationships.

关键词： paleoanthropological sites paleoenvironments database quaternary

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Science china Earth sciences 2010年第1期53卷 54-63页

作者： FU LiYun key laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese academy of sciences,beijing 100029,china 1. key laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

How a wave interacts with heterogeneous media has been pursued by many *** complexity of subsurface heterogeneities is seismologically a relative concept to wavelengths of seismic waves.A growing perception is that velocity variations,propagation angles,and computational accuracies are closely related at a variety of scales.A tentative strategy to quantitatively evaluate the complexity of subsurface heterogeneous media is presented in this article to see what scales of geological heterogeneities to be captured by *** express complex subsurface structures as the slowness-and angularheterogeneity spectra to quantify velocity contrasts and dipping-angle distributions of complex geological *** the other hand,the scaling characteristics of a propagator are measured through dispersion analysis by its angular spectra plotted against refractive indexes and propagation angles,respectively.A parameter termed as imaging efficiency is introduced by associating the geological heterogeneity spectra with the propagator's angular spectra to understand the coherent interference between the medium's heterogeneity and the propagator's scaling ***,a complexity coefficient can be defined to evaluate geological complexities in terms of *** application of this strategy is demonstrated to the SEG/EAEG salt model.

关键词： geological heterogeneity spectra seismic imaging propagator’s angular spectra imaging efficiency complexity coefficient

PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia:Indicator to source of metallogenic elements

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chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU Meifuinstitute of geology and geophysics, chinese academy of sciences, beijing 100029, china key laboratory of Mineral Resources, institute of geology and geophysics, chinese academy of sciences, beijing 100101, china Department institute of geology and geophysics Chinese Academy of Sciences Beijing China key laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

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Progress in Natural Science:Materials International 2007年第3期17卷 305-313页

作者： YAN Zhen, YU Liangjun, LI Jiliang, BIAN Qiantao, WANG Zongqi and YANG Yongcheng ( institute of geology, chinese academy of Geological sciences, beijing 100037, china State key laboratory of Lithospheric Evolution, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china Shaanxi Insititute of geology Survey, Xianyang 712000, china) [a]institute of geology Chinese Academy of Geological Sciences Beijing China [b]State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [c]Shaanxi Insititute of geology Survey Xianyang China

The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy, and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.

关键词： Middle-Upper Triassic fluvial-lake environments tide environment tempestite Songpan-Ruoergai

^(40)Ar/^(39)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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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.

Quantitative Evaluation of the Sea-level Drop at the End-Permian: Based on Reefs

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 95-102页

作者： WU Yasheng and FAN Jiasong institute of geology and geophysics, chinese academy of sciences, beijing 100029 chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

The amplitude of pre-Quaternary sea level drop, H, can be calculated by usingthe formula H = D + To, where To is the original thickness from the top of the tidal deposits onthe reef core to the bottom of the tidal deposits on the reef front, or to the bottom of the ancientmeteoric vadose zone, or to the edge of the mixed-water dolostone zone. The identity and similaritybetween the sea-level drop amplitudes calculated from different reefs far away from each otherindicates that such sea-level changes are eustatic rather than relative changes. Evidence of anend-Permian sea-level drop has been found on the Changxingian (i.e. the end of the Palaeofusulinazone) reefs at Ziyun in South china, including algal laminated deposits, sabkha-related dolostone,desiccation cracks, dissolution collapse breccia. According to calculation based on the meteoricdissolution zone of the reef-core sequence at Ziyun, Guizhou province, the amplitude of thesea-level drop at the end-Permian is about 89.3 m. Calculation via the dolomitized upper part of theChangxingian reef in Lichuan, Hubei Province, yields an 88.9 m amplitude of the sea-level drop atthe end-Permian. Comparison shows that the sea-level drop recorded in the two distantly locatedreefs may be of eustatic type. So the amplitude of the sea level drop of the Tethys Sea at theend-Permian might be at least 89.3 m.

关键词： sea-level drop eustatic reef Permian Changxingian

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science china Earth sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. key laboratory of Mineral Resources, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. beijing institute of geology for Mineral Resources, beijing 100012, china Correspondence should be addressed to Wang Lijuan (email: wlj@***) 1. key laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. beijing institute of geology for Mineral Resources 100012 Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North china Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of Resources sciences & Technology, beijing Normal University, beijing 100875, china key laboratory of Gas Geochemistry, institute of geology and geophysics, chinese academy of sciences, Lanzhou 730000, china) [a]College of Resources sciences & Technology Beijing Normal University Beijing China [b]key laboratory of Gas Geochemistry Institute of Geology and Geophysics Lanzhou China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13C1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4 values available for utilization vary from - 333‰ to - 117‰, and δ13CCO2 values from - 29. 4‰ to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13C1 and δ13CCO2 values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13C1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.