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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 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 Academy of Geological Sciences, Beijing 10003., china 2. Development and Research Center, china Geological Survey, Beijing 10003., china 3. china University of Geosciences, Beijing 100083. china 4. china University of Geosciences, Wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812, china 6. institute of geology, State Seismological Bureau, Beijing 100029, china 1. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of Geosciences 100083 Beijing China 4. china University of Geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. institute of geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, 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 china 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 china Platform is a remnant of cratonic lithosphere after the North china 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 china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china 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 china 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

Laser glazing study of Co-based alloy and Ni-Nb-Cr alloy coating

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Chinese Journal of Lasers 1994年第4期B3卷 377-384页

作者： TIAN Nailiang(Department of Applied Physics,tianjin institute of Science and Technology, tianjin 3.0191,{3.)YANG Yongqiang(Department of Mechanics, tianjin institute of Textile Science and Technology,tianjin 3.0160, china) tianjin Inst of Science and Technology Tianjin China

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关键词： Metallic glass cladding layer Co-based

Carbon and hydrogen isotopic characteristics of natural gases from the Luliang and Baoshan basins in Yunnan Province, china

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Science china Earth Sciences 2006年第9期49卷 938-946页

作者： XU Yongchang1, LIU Wenhui2, SHEN Ping1, WANG Wanchun1, WANG Xiaofeng1, Tenger1, YAN Yaomin3.& LIU Ruobin3.1. Lanzhou Center of Oil & Gas Resources, institute of geology and Geophsics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Research institute of Petroleum Exploration and Production, SINOPEC, Beijing 100083. china 3. South Branch of Petroleum Exploration and Production Company, SINOPEC, Kuming 650000, china 1. Lanzhou Center of Oil & Gas Resources Institute of Geology and Geophsics Chinese Academy of Sciences Lanzhou 730000 China 2. Research institute of Petroleum Exploration and Production SINOPEC Beijing 100083 China 3. South Branch of Petroleum Exploration and Production Company SINOPEC Kuming 650000 China

The Luliang and Baoshan basins of Yunnan Province are two small-sizedcontinental oil/gas-bearing sedimentary basins, which were developed at the bases of theCarboniferous and Devonian systems during the Late Tertiary, covering an area of 3.5 km^2 and 254km^2, respectively. Since the 1990s, there have been discovered small-sized natural gas pools inthese two basins. The natural gases are composed mainly of hydrocarbon gases, with nonhydrocarbonsaccounting for less than 2%. Of the hydrocarbon gases, methane accounts for more than 99%, and thecomponents above C_2 account for less than 0.2%. On the basis of previous studies of geologicalbackground, the composition of natural gases and their carbon isotopic composition, it has beendefined that these two gas pools are of bacterial origin. In this work we have comprehensivelymeasured the carbon and hydrogen isotopic composition of natural gases from these two basins andhave gone into the details of the mechanism of gas generation. The δ^(13.C_1 values of naturalgases from the Luliang Basin are within the range of -72.1 per thousand - -73.3.per thousand, andthe δD_(CH_4) values, -242 per thousand - -23. per thousand, indicating that the bacterial gasgeneration is dominated by the way of CO_2 reduction. It has been evidenced that undercontinental-facies fresh water conditions there did occur the CO_2 reduction as a process ofbacterial gas generation. The δ^(13.C_1 values of natural gases from the Baoshan Basin are withinthe range of - 62.5 per thousand - -63.5 per thousand, and the δD_(CH_4) values, -252 per thousand- -260 per thousand. These isotopic characteristics are fallen into transitional phase of acetatefermentation and CO_2 reduction as defined by Whiticar et al. (1986). An important discovery in theLuliang Basin is the carbon isotopic composition of ethane of purely biogenetic origin, i.e., itsδ^(13.C_2 values are within the range of - 61.2 per thousand - - 66.0 per thousand. These carbonisotopic values have been r

关键词： bacterial gas, carbon and hydrogen isotope, CO2 reduction, acetate fermentation.

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and mineral Resources, china University of Geosciences, Wuhan 43.074, china 2. {3. of Resources & Environments, Henan Polytechnic University, Jiaozuo 454003. china 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 43.074, china 4. Laboratory of Marine geology, Tongji University, Shanghai 200092, china Faculty of Earth Science and State Key Laboratory of Geological Processes and mineral Resources china University of Geosciences Wuhan china institute of Resources & Environments Henan Polytechnic University Jiaozuo china Department of Computer Science South-Central University for Nationalities Wuhan china Laboratory of Marine geology Tongji University Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china Earth Sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3. LI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china 2. institute of Geophysics, Chinese Seismological Bureau, Beijing 100081, china 3. institute of Deposition Resource, Chinese Academy of Geological Sciences, Beijing 10003., china 1. institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

Estimates of Central Moments for One Kind of Exponential-Type Operators

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Transactions of tianjin University 2011年第2期17卷 85-88页

作者：宋占杰杨振东叶培新 School of Sciences Tianjin University institute of TV and Image Information Tianjin University School of Mathematics and LPMC Nankai University

In this paper,the explicit estimates of central moments for one kind of exponential-type operators are *** estimates play an essential role in studying the explicit approximation properties of this family of *** the proposed method,the results of Ditzian and Totik in 1987,Guo and Qi in 2007,and Mahmudov in 2010 can be improved respectively.

关键词： exponential-type operator central moment approximation property Stirling series

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3.4, ZHANG Hucai2, WANG Weiguo3.& AN Chenbang3.1. Nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Nanjng institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, china 3. Environment and Resources College, Lanzhou University, Lanzhou 73.000, china 4. Beijing Normal University, Beijing 100875, china 1. Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23.ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural Resources, china University of Geosciences, Beijing 100083. china 2. Faculty of Earth Sciences, china University of Geosciences, Wuhan 43.074, china 3. Beijing SHRIMP Center, institute of geology, Chinese Academy of Geological Sciences, Beijing 10003., china 1. Faculty of Earth Sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China 3. Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Hydrocarbon test in lower-layer atmosphere to predict deep-sea petroleum or hydrate in the Okinawa Trough: an example

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Acta Oceanologica Sinica 2003年第4期22卷 569-576页

作者： Gong Jianming1, Chen Jianwen 1, 2, Li Gang1, Zhang Xunhua1, Li Jipeng3. Huang Fulin1 1. Qingdao institute of Marine geology, Qingdao 266071, china. 2. Ocean University of china, Qingdao 266003. china 3. Hefei institute of Petroleum Chemical Exploration, china Petroleum Exploration and Development Research institute, Hefei 23.022,china Qingdao Inst Marine Geol Qingdao 266071 Peoples R China Ocean Univ china Qingdao 266003 Peoples R China china Petr Explorat & Dev Res Inst Hefei Inst Petr Chem Explorat Hefei 230022 Peoples R China

Light hydrocarbon (methane, ethane, propane, butane and CO2) test and C isotopic analysis of CO are conducted for over 100 lower-layer atmospheric samples from the East china Sea slope and the Okinawa Trough. The results show that the lower-layer atmosphere mainly consists of CO2 and then of CH4, and the CO2 concentrations are calculated to have a high average value of 0.87 omega/10(-2) about three times that of the regional background (0-3.omega/10(-2)). The result also shows that the average value of C isotope - 20.8 x 10(-3. is given to the CO2, inferring that it is inorganic gas. Thus, for the future 's work in the Okinawa Trough, special attention should be paid to CO2 hydrate, which is very possibly an important hydrate type.

关键词： lower-layer atmosphere hydrocarbon test C isotopic analysis deep-sea petroleum gas hydrate