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Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(39)Ar age dating of Dur'ngoi ophiolite

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Chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI Xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, Northwest University, Xi’an 710069, china 2. Department of geology, Northwest University, Xi’an, 710069, china 3. institute of geology, Chinese academy of geological sciences, beijing, 100037, china Laboratory of Continental Dynamics Northwest University Xi’an China Department of geology Northwest University Xi’an China institute of {1. Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/39Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (345.3±7.9 Ma) with an isochorn age (336.6±7.1.Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -39Ar age Paleo-tethys.

Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern china

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 365-379页

作者： Liu Xun institute of {1., Chinese {2. of geological sciences, beijing CHINESE ACAD GEOL SCI INST GEOLBEIJINGPEOPLES R CHINA

Since Jurassic. intense and repeated tectonic movements have taken place in eastern china, of which theYanshanian movement is the most important. Thereby the development of the basins between the Jurassic andEogene in the studied areas may by divided into two different stages, i.e. the Yanshanian subcycle （J-K;） andthe North china subcycle （K;-E）. The basement and tectonic stress field of the basins played an obvious role in controlling thesedimentary-tectonic development of the basins. and down-faulted basins might form under different stressstates. Besides. the shearing stress also played an important part while the basins were forming in the notedareas.

关键词： Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern china

geological analysis and physical modeling of structural pumping in high effective formation of Kela {1.gas field

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Science china Earth {1. 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1. WANG Hongjun1. SHAN Jiazeng2. WANG Zecheng1.& XU Dafeng1.1. Research {1. of Petroleum Exploration and Development, Petrochina, {2. 1.0083, china 2. institute of geology and Geophysics, Chinese academy of sciences, {2. 1.002., china 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela {1.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

High-temperature phases of pyrophyllite and their evolutionary characteristics

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Chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, Chinese {1. of {2., Changsha 41.01., china 2. institute of geology, Chinese {1. of {2., beijing 1.002., china Changsha institute of Ceotectonics Chinese Academy of Sciences Changsha China institute of {1. Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1.50℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1.1.℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2. LI Anchun1, HU Ningjing2.3, FU Yongtao1& MA Zhibang4 1. institute of Oceanology, Chinese academy of {2., Qingdao 2.6071, china 2. Graduate School of the Chinese academy of {2., beijing 100039, china 3. institute of Soil Science, Chinese academy of {2., Nanjing 2.0008, china 4. institute of geology and Geophysics, Chinese academy of {2., beijing 10002., china 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the Chinese {1. of sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of {1. and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

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

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Science china Earth {1. 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 {2. of sciences,Nanjing 2.0008,china 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. institute of geology and Geophysics,Chinese {2. of sciences,beijing 10002.,china Nanjing institute of {1. and Paleontology Chinese Academy of Sciences Nanjing 210008 China Anthropology and Sociology Department Santa Clara University CA 95053 United States institute of {1. 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 1.000 and 872. 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 872. 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 42.0?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2.70 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2.70 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.

A Possible Long-tailed Bird with a Pygostyle from the Late Mesozoic Yixian Formation, Western Liaoning, china

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Acta Geologica Sinica(English Edition) 2005年第1期79卷 7-10页

作者： L Junchang1 and HOU Lianhai2.1 institute of geology, Chinese {2. of geological sciences, beijing 100037 2.institute of Vertebrate Paleontology and Paleoanthropology, Chinese {2. of sciences, beijing 100044 Department of Biology, Capital Normal University, beijing 100037 Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China Capital Normal Univ Dept Biol Beijing 100037 Peoples R China

An incomplete caudal vertebral series (IVPP V1.309) from the Yixian Formation of late Mesozoic, Jianshangou area of Beipiao, western Liaoning Province, may represent a new bird. The tail is composed of at least 1.0}free caudal vertebrae and the most distal 5 caudal vertebrae co-ossified into a pygostyle. The pygostyle is plate-like and slightly curved dorsally. The anterior free caudals are amphiplatyan. The anterior caudal surfaces of the last three free caudals are concave, but their posterior articular surfaces are convex. The pygostyle is regarded as the first appeared flight apparatus during the evolutionary process from Archaeopteryx to neornithes. The pygostyle appeared in most early fossil birds and almost all the modern birds. Although their morphologies are different, they are basically formed by at least four last caudal vertebrae. The specimen V1.309 is regarded as a bird rather than a non-avian theropod dinosaur based on the following characters: short caudal vertebrae, numerous pits present on the surfaces of the centra and, a foramen present between the basal part of the fused neural spines, which is similar to that of Struthio camelus. The discoveries of pygostyles from the therizinosauroids and oviraptorosaurs may provide strong evidence for supporting the origin of birds from small theropod dinosaurs. The structure of the pygostyle in specimen V1.309 is different from those of Beipiaosaurus (Therizinosauroid) and Nomingia (oviraptorosaur). The most parsimonious interpretation is that these pygostyle-like structures are independently acquired by Beipiaosaurus and Nomingia during their evolutionary process.

关键词： western Liaoning Yixian Formation late Mesozoic pygostyle

Gymnosperms on the eve of the terminal Permian mass extinction in North china and their survival strategies

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Chinese Science Bulletin 1998年第11期43卷 889-897页

作者： WANG Ziqiang+1.and ZHANG Zhiping+2. 1. Tianjin {1. of geology and Mineral Resources, Chinese {2. of geological sciences, Tianjin 3001.0, china 2. Tianjin Centre of Physical and Chemical Techniques, Tianjin 300050, china Tianjin institute of {1. and Mineral Resources Chinese Academy of Geological Sciences Tianjin China Tianjin Centre of Phyhical and Chemical Techniques Tianjin China

Main characteristics of the Permian redbed gymnosperms in North china have been summarized: dominant peltasperms and conifers, numerous enigmatics such as Gigantonoclea and Psygmophyllum, and abundant precursors of Mesozoic gymnosperms. Furthermore, stresses affecting these plants survival are suggested to be paleoatmospheric CO-{1.concentration, water stress, wind and fire activities, and fungal infection. Consequently, a preliminary analysis accounts for the ecological strategies of these gymnosperms to the P-Tr event.

关键词： North china Permian gymnosperms mass extinction.

Lithosphere types in North china:Evidence from {1. and geophysics

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Science china Earth {1. 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. institute of geology, Chinese {2. of geological sciences, beijing 100037, china 2. Development and Research Center, china geological Survey, beijing 100037, china 3. china University of Geosciences, beijing 100083, china 4. china University of Geosciences, Wuhan 430074, china 5. Information Center of Ministry of Land and Resources, beijing 100812. china 6. institute of geology, State Seismological Bureau, beijing 10002., china 1. institute of {1. Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of Geo{1. 100083 Beijing China 4. china University of Geo{1. 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. institute of {1. State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North{1., three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North{1. platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North{1. Platform is a remnant of cratonic lithosphere after the North{1. platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North{1. craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North{1. platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North{1. in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process