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A preliminary study on seismic design criteria of offshore platforms in Bohai Sea of China

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 223-231页

作者： Peng Yanju1,Lu Yuejun1,Yan Jiaquan2,Tang Rongyu1,Wang Junqin3.and Li Jiagang3.1. Institute of Crustal Dynamics,China Earthquake Administration,Beijing 100085,China 2. Institute of Geophysics,China Earthquake Administration,Beijing 100081,China 3. Beijing Research Center of China National Offshore Oil Corp.,Beijing 100027,China Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

This paper analyzes the seismicity in Bohai Sea,introducing a shape factor K to characterize the seismic risk distribution in sub-regions of the sea. Based on the seismic design ground motions for 46 platforms located in the Bohai Sea,a statistical analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method,a scheme of two seismic design levels is proposed,and two seismic design objectives are established respectively for the strength level earthquake and the ductility level earthquake. By analogy with and comparison to the Chinese seismic design code for buildings,it is proposed that the probability level for the strength level earthquake and ductility level earthquake have a return period of 200 and 1000 - 2500 years,respectively. The validity of these proposed values is discussed. Finally,the PGAs corresponding to these two probability levels are calculated for different sub-regions of the Bohai Sea.

关键词： fixed offshore platform seismic design level seismic design objective return period Bohai Sea

Discovery of seep carbonate nodules as new evidence for gas venting on the northern continental slope of South China Sea

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Chinese Science Bulletin 2006年第10期51卷 1228-1237页

作者： CHEN Zhong1,2,3. YAN Wen1,2,3. CHEN Muhong1,3. WANG Shuhong1,2,3. LU Jun1,3. ZHANG Fan1,3. XIANG Rong1,3. XIAO Shangbin1,3. YAN Pin1,2,3.& GU Senchang1,2,3.1. South China Sea Institute of Oceanology, Chinese Academy of Sci-ences, Guangzhou 5103.1, China 2. Guangzhou Center for Gas Hydrate Research, Chinese Academy of Sciences, Guangzhou 5103.1, China 3. Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 5103.1, China South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou China Guangzhou Center for Gas Hydrate Research Chinese Academy of Sciences Guanzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Seep carbonate nodules were firstlycollected from the southwestern Dongsha area onnorthern continental slope of South China Sea formineralogical and geochemical studies. The resultsof X-ray diffraction show that carbonate nodules arecomposed of Fe-rich domolite,siderite and a few cal-cite and aragonite, as well as a small quantity ofnon-carbonate minerals such as goethite, quartz andclay minerals. Fe-rich dolomite and siderite charac-terized by euhedral microcrystalline structure weredirectly precipitated at cold seeps. The δ 13. valuesfor Fe-rich dolomite and siderite in the bulk nodulesvary from ?18.24‰ to ?3..07‰, and the δ 18O valuesrange from 0.42 to 2.76‰. Their moderate depleted13. reflects that carbon origin is possibly thermoge- netic gas or mixed gas, which is evidence of gasventings in the seafloor. Moreover, massive wormtube fossils related to cold seeps were found on thesurfaces of carbonate nodules, and the conduitsand/or channels in semi-solidified nodules whichwere not filled by carbonate or sediment were alsoobserved. A preliminary conclusion is that activemicro gas venting with a conduit/channel diameterrange from 200 μm to 600 μm possibly exists inmodern seafloor of the carbonate nodule area.

关键词：渗出碳酸盐节碳氧同位素甲烷渗漏天然气水化物

Detection of water in petroleum inclusions and its implications

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Science Bulletin 2006年第12期51卷 1501-1507页

作者： CAO Jian1, YAO Suping1, HU Wenxuan1, ZHANG Yijie2, WANG Xulong3. ZHANG Yueqian3.& TANG Yong3.1. State Key Laboratory for Mineral Deposit Research, Department of Earth Sciences, Nanjing University, Nanjing 210093. China 2. Research Institute of Exploration and Development, PetroChina, Bei- jing 100083. China 3. Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 83.000, China State Key Laboratory for Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China Research Institute of Exploration and Development PetroChina Beijing 100083 China Research Institute of Exploration and Development Xinjiang Oilfield Company PetroChina Karamay 834000 China

FTIR spectra of inclusions sampled from fault-zone reservoirs of the northwestern Junggar Basin show that water, with different abundances, does exist in petroleum inclusions. It is thus implied that petroleum inclusions can seldom form without water. Different inclusions hosted in one single grain, and formed in one oil charging phase, have a largely varied ratio of water to oil and slightly changed CH3.CH2 ratio. This likely provides evidence for fault-related episodic migration and accumulation of hydrocarbons.

关键词： water in petroleum inclusions forming mechanism of inclusions episodic migration and accumulation of hydrocarbons FTIR microspectroscopy Junggar Basin.

Thermodynamic Analysis of the Preparation Process of EB-PVD SiC Coating

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 363-366页

作者：易剑 School of Mechatronics Engineering Taizhou University Laser Processing Center Tianjin Polytechnic University Center for Composite Materials Harbin Institute of Technology

The process of preparing SiC coating by electron beam-physical vapor deposition （EB-PVD） was discussed from viewpoint of thermodynamis. Results show that within the temperature range of 2 700-3.3.0 K, the ratio of SiC in the SiC coating doesn＇t change much and keeps around 0.7. Purity of the as-deposited SiC coating is not high. To improve the purity of the SiC coating, the SiC ingot is required to not be, necessary in full density but be fine-grained.

关键词： thermodynamics SiC coating EB-PVD ratio of SiC purity

Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3., LI Congxian\+1 and CONG Youzi\+2 1. Marine Geology Laboratory, Tongji University, Shanghai 200092, China 2. First Institute of Oceanography, State Oceanic Administration of China, Qingdao 266003. China 3. Guangzhou Institute of Marine Geology Laboratory Tongji University Shanghai China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China First Institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

Singular Integral Equations with Cosecant Kernel in Solutions with Singularities of High Order

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Wuhan University Journal of Natural Sciences 2005年第2期10卷 339-343页

作者： HAN Hui-li 1,2 ,DU Jin-yuan 1,3.1. School of Mathematics and Statistics, Wuhan University, Wuhan 43.072, Hubei, China 2. School of Mathematics and Computer, Ningxia University, Yinchuan 750021, Ningxia, China 3. Department of Mathematics, Hubei Institute for Nationalities, Enshi 445000, Hubei, China Wuhan University School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Ningxia University School of Mathematics and Computer Yinchuan Ningxia China (GRID:grid.260987.2) (ISNI:***) Wuhan University School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Hubei Institute for Nationalities Department of Mathematies Enshi Hubei China (GRID:grid.34418.3a) (ISNI:***)

We have discussed and solved the boundary value problem with period 2aπ and the singular integral equation with kernel csc t-tv/a in solution having singularities of high order, where the smooth contour of integratio... 详细信息

关键词： boundary value problem singular integral equation the singularities of high order

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science China(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3. WANG Guilan1 & ZHENG Qiguang2 1. School of Material Science and Technology, Huazhong University of Science and Technology, Wuhan 43.074, China 2. Institute of Laser Technology and Engineering, Huazhong University of Science and Technology, Wuhan 43.074, China 3. Mechanical Engineering College, Hubei University of Technology, Wuhan 43.068, China 1. School of Material Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering College Hubei University of Technology Wuhan 430068 China 2. Institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

The reconstruction and interpretations of lake status at 6 ka and 18 ka *** inland mainland Asia

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Chinese Science Bulletin 1998年第14期43卷 1145-1157页

作者： QIN Boqiang 1, SHI Yafeng 1 and YU Ge 2, 3.1. Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China 2. Dynamic Palaeoclimatology, Lund University, PO Box 117, S 221 00, Lund, Sweden 3. Department of Nanjing Institute of Geography & Limnolagy Chinese Academy of Sciences Nanjing China Dynamic Palaeoclimatology Lund University Lund Sweden Department of Geology and Ocean Sciences Nanjing University Nanjing China

By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 18 ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 18 ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. Conversely, the lakes from the eastern and southern Asia registered comparative low levels at 18 ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 18 ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the Central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 18 ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies.

关键词： lake status inland mainland Asia westerlies monsoon.

^(40)Ar/^(3.)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 10003., 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 3.0℃. 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/3.Ar dating, late Cenozoic.