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Paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the chinese Loess Plateau since 8.0 Ma B.P.

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Science china Earth Sciences 2006年第5期49卷 518-530页

作者： XUE Xiangxu1,2. ZHANG Yunxiang1,2.& YUE Leping1,2.1. State Key Laboratory of Continent Dynamics (Northwest University), institute of Cenozoic {4. and Environment, De- partment of {4., Northwest University, Xi’an 710069,{3. 2. institute of Earth Environment, State Key Laboratory of Loess and Quaternary {4., chinese Academy of Sciences, Xi’an 710075,{3. 1. State Key Laboratory of Continent Dynamics (Northwest University) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an 710069 China 2. institute of Earth Environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an 710075 China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12.stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.P. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the Pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the Pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess Plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-Xizang (Tibet) Plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess Plateau.

Mid-Holocene climate change in North china, and the effect on cultural development

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chinese Science Bulletin 2002年第5期47卷 408-413页

作者： JIN Guiyun & LIU Dongsheng (LIU Tungsheng)institute of Cultural Relics and Archaeology of Shandong Province, Jinan 2.0012. china institute of {3. and geophysics, chinese Academy of Sciences, Beijing 10002., china institute of Cultural Relics and Archaeology of Shandong Province Jinan China institute of geology and {2. Chinese Academy of Sciences Beijing China

In this study, to reconstruct the paleoclimatic history, pollen and oxygen isotope were analyzed on the 160 samples of a 2.7 m peat core from Taishizhuang, Huailai County, Hebei Province. Combining our data with other information of climate history and archaeology from this area, we found that there is a close linkage between cultural development and the mid-Holocene (6000-3.00 cal. aBP) environment changes. The main results and conclusions are presented as the following: The climate during 5678-54.0 cal. aBP was unstable and in general colder and drier than today. From 54.0 to 4.00 cal. aBP the climate was much warmer and wetter than before. The climate during 4.00-4.1}0 cal. aBP was persistently cold, with an exceptional cold event occurring at 4.00-4.1}0 cal. aBP. This cold event was recorded at several other localities in Northern{4. even the Northern Hemisphere and played an important role in the cultural development. After the cold event, there was a return to warmer conditions between 4.0}0 and

关键词： North china peat mid-Holocene cold event cultural development.

Risk-opportunity analyses and production peak forecasting on world conventional oil and gas perspectives

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Petroleum Science 2010年第1期7卷 136-146页

作者： Zhang Jian Sun Zandong Zhang Yiwei Sun Youshun Nail Toksoz ~Lab for Integration of geology and geophysics China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China Earth Resources Laboratory Massachusetts Institute of Technology 77 Mass. Ave Cambridge MA 02139 USA

To investigate the situation of conventional oil and gas, this paper examines the global oil and gas discoveries, proved reserves, production, consumption and price. All the influencing factors can be subjected to risk and opportunity analyses, so in the paper, we build upon a risk-opportunity analysis framework, which is a new train of thought. To forecast the peak time of oil and gas production, we used the methods of multi-Hubbert model forecasting and data forecasting. Our results showed that the world oil production will reach a peak between 2.10 and 2.15 and the gas production will reach a peak around 2.3. Oil peak is coming and gas peak is on the way. The main purpose of forecasting oil and gas production peak is give people enough time for preparing mitigation and adaptation plans. This means taking decisive action well before the problem is obvious.

关键词： Production reserve risk opportunity forecasting

Landscape evolution and palaeoclimate in the deserts of northwestern china,with a special reference to Badain Jaran and Taklamakan

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chinese Science Bulletin 2001年第S1期46卷 6-11页

作者： YANG Xiaopinginstitute of geology and {2., {3. Academy of Sciences, Beijing {4., china (e-mail: xpyang@public2.east. ***) 1. institute of geology and {2. Chinese Academy of Sciences 100029 Beijing China

A comparative study of geomorphologic landscapes in the Badain Jaran Desert and Taklamakan Desert was made on the basis of field investigations, thermolumi-niscence and radiocarbon dating as well as analysis of sand grain texture. The sand seas of the Badain Jaran Desert differ greatly from that of the Taklamakan Desert in terms of dune morphology, interdune relief, dune stratigraphy and sand sources. The thermoluminiscence ages of the dunes suggest that the basic configuration of the megadunes in the Badain Jaran Desert has not changed at least since Middle Holocene. There were periods of more humid environment during the last glaciation and Holocene in both deserts, but events of higher precipitation in the Badain Jaran Desert were more frequent than in the Taklamakan. In both desert areas, aeolian processes have been intensified during the last 2.00 a.

关键词： desert sand seas palaeoclimate landscape northwestern china.

Mineralization dynamics of Paishanlou gold deposit in Fuxin, Liaoning Province

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chinese Science Bulletin 1999年第S2期44卷 188-190页

作者： LlU Jianzhong~1, OUYANG Ziyuan~1, LlU Xishan~2.and ZHANG Fuqin~3.1. institute of Geochemistry, {2. Academy of Sciences, Guiyang 550002. china 2. Changchun University of Science and Technology, Changchun 13.02., china 3. institute of geophysics, {2. Academy of Scienees, Beijing 100101, china

FROM the 1980s of this century, the very great advances in Precambrian geology and deposits, such as thefinding of Abitibi gold deposit in Quebec Province of Canada bearing on Archaean Greenstone Belts havecaused a progressive effect to show that the large and ultra-large deposits have something to do with ductile shear zones (DSZ). During the past 10 years, a lot of DSZ were recognized at several places inchina, specially at the geological background areas of Precambrian and granite district. Meanwhile somelarge gold deposits have been discovered at Heitai, Paishanlou, Jinshan and Jiapigou, which formed inDSZs. Thus, the study of the relationship between gold deposits and DSZ has important significance forthe {2. noble metal industry.

关键词： mineralization dynamics Paishanlou gold deposit Liaoning Province.

Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science china Earth Sciences 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2.3.4.SUN BaiNian 1,2.,LI XiangChuan 1,REN WenXiu 1 &JIA Hui 1 1 Key Laboratory of Western china's Environmental Systems of the Ministry of Education and College of Earth and Environment Science,Lanzhou University,Lanzhou 73.000,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of {3. and Palaeontology,chinese Academy of Sciences,Nanjing 2.0008,china 3.College of Arts and Sciences,Bryant University,Smithfield RI 02.17,U.S.A. 4.Key Laboratory of Western china's Mineral Resources and Geological Engineering of Ministry of Education,Chang’an University,Xi’an 710054.china 1. Key Laboratory of Western china’s Environmental Systems of the Ministry of Education and College of Earth and Environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 4.%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

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Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2.& PAN Guitang2.1. Geoscience College, Chengdu University of Technology, Chengdu 610059, china 2. Chengdu {4. of {2. and Mineral Resources, Chengdu 610082. china 1. Geoscience College Chengdu University of Technology Chengdu 610059 China 2. Chengdu institute of geology and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

Project research of GIS data based on AutoCAD

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中国有色金属学会会刊：英文版 2005年第S1期15卷 244-246页

作者： YAO Xin ~(1, 2. (1. institute of geology and {2., {{4. Academy of Sciences, Beijing 10002., china 2. The Geomatics and Applications Laboratory, Liaoning Technical University, Fuxin 12.3}00, china) chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Liaoning Tech Univ Geomat & Applicat Lab Fuxing 123000 Peoples R China

The digitalization software developed based on AutoCAD is one important platform of GIS data gather. But because AutoCAD itself is not the software of GIS, it can not be used to collect the attribute data. And conversion data to GIS software often lose some information such as color, line style, symbol shape. By using the XDATA, the Handle, the Group of AutoCAD and the provided ObjectArx to Redevelop, under AutoCAD condition, the attribute information collection with space information were realized, also did the AutoCAD symbol integrity and accurate expresses, then the demand of the digit graphics was satisfied.

关键词： AutoCAD attribute data data transfer ObjectArx XDATA

Early-Middle Permian Reef Frameworks and Reef-building Models in the Eastern Kunlun Mountains

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Acta Geologica Sinica(English Edition) 2001年第2期75卷 115-125页

作者： TIAN Shugang institute of geology, {2. Academy of Geological Sciences, Beijing 10003.and FAN Jiasong institute of geology and geophysics, {2. Academy of Sciences, Beijing 10002. institute of geology Chinese Academy of Geological Sciences Beijing 100037 institute of geology and {2. Chinese Academy of Sciences Beijing 100029 [?]3.ian Shugang Born in September 1951 graduated from Beijing University in 1977 and received his MS. and Ph. D. degrees at china University of Geosciences (Beijing) in 1985 and 1988 respectively working now in the institute of geology Chinese Academy of Geological Sciences. He has long been engaged mainly in studies of biostratigraphy palaeoecology sequence-stratigraphy and reefs. Tel: 010–68328223 E-Mail: sgtian2.01@***

Reef frameworks and building models of the Early-Middle Permian in the eastern Kunlun Mountains have been verified through studies of reef-building communities, palaeoecology and carbonate facies. The eastern Kunlun reefs are built mainly by 6 reef-building communities, which include 11 major categories of frame-building organisms and 6 categories of reef-associated organisms. Eight types of reef-frames have been distinguished and eleven kinds of rocks identified to belong to 6 reef facies. Three sorts of reefs classified by previous researchers, namely mudmounds, knoll reefs and walled reefs, are well developed in the study area. Such reef-facies association and reef distribution show that there are 4.models of reef growth and development, i.e. the tidal-bank knoll-reef model, the plateau-margin wall-reef model, the composite wall-reef model and the deep-water mudmound model. The reefs are mainly constructed by calcareous sponge and calcareous algae, which are similar to all Permian reefs in other area

关键词： reef model Early-Middle Permian eastern Kunlun reefs