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Chronological and geochemical studies of granite and enclave in Baimashan pluton, Hunan, South china

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Science china Earth Sciences 2007年第11期50卷 1606-1627页

作者： CHEN WeiFeng1, CHEN PeiRong1, HUANG HongYe2, DING Xing1,3.& SUN Tao1 1 State Key Laboratory of Mineral Deposit Research, Department of Earth Sciences, Nanjing University, Nanjing 210093. china 2 Research institute No.23., CNNC, Changsha 410011, china 3.{3. institute of Geochemistry, chinese academy of Sciences, {3. 510640, china 1. State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. Research institute No.23. CNNC Changsha 410011 China 3. guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (204.5±2.8 Ma-209.2±3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (203.2±4.5 Ma-205.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 221.4±4.0 Ma to 226.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3.10±20.6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87Sr/86Sr)i ratios, and old T2DM (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of Sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

关键词： granite,mafic microgranular enclave,zircon LA-ICP-MS dating,lithogenesis,EC-AFC

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2 , ZHANG Youshui 3. 1. institute of Mountain Hazards and Environment, chinese academy of Sciences, Chengdu 610041, Sichuan,{3. 2. Graduate University of chinese academy of Sciences, Beijing 100049,{3. 3. institute of Geographical Sciences and Natural Resources Research, chinese academy of Sciences, Beijing 100101,{3. institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of Sciences 100049 Beijing China institute of Geographical Sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 259 basic data of 3. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3.& ZOU BingSong1,2,3.1 institute of High Energy Physics,chinese academy of Sciences,Beijing 100049,{3. 2 Theoretical Physics Center for Science Facilities,chinese academy of Sciences,Beijing 100049,{3. 3.Graduate University of chinese academy of Sciences,Beijing 100049,{3. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of Sciences Beijing 100049 China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3.and Meng Dazhi2(1. National Laboratory of Pattern Recognition,institute of Automation, chinese academy of Sciences, Beijing 100080,{3. 2. College of Applied Sciences, Beijing University of technology, Beijing 100022,{3. 3. School of Science, Beijing institute of technology, Beijing 100081,{3.) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China School of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2,3.& LI Gaicheng1,3.1. Engineering Research Center for Information Security technology, institute of Software, chinese {3. of Sciences, Beijing 100080, china 2. Beijing Zhongke Ansheng Corporation of Information technology, Beijing 100080, china 3. Graduate School of the chinese {3. of Sciences, Beijing 10003., china 1. Engineering Research Center for Information Security technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Beijing Zhongke Ansheng Corporation of Information technology Beijing 100080 China 3. Graduate School of the chinese academy of Sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2 & HUA Feng1,2,3.1. institute of Oceanology, chinese academy of Sciences, Qingdao 266071,{3. 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 266061,{3. 3. Graduate School of the chinese academy of Sciences, Beijing 10003.,{3. 1. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School of the chinese academy of Sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3.& WANG Huijun2 1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, chinese academy of Sciences, Beijing 100029,{3. 2. Department of Atmospheric Science, Yunnan University, Kunming 650091,{3. 3. Graduate University of the chinese academy of Sciences, Beijing 100049,{3. 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the chinese academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South china Sea

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Science china Earth Sciences 2006年第8期49卷 839-850页

作者： LIU Baoming1,2,3. XIA Bin1, LI Xuxuan1,3. ZHANG Minqiang1,3. NIU Binhua2, ZHONG Lifeng1, JIN Qinghuan1,4 & JI Shaocheng1,5 1. Key Laboratory of Marginal Sea Geology and Resources, chinese academy of Sciences,guangzhou 510640,{3. 2.{3. University of Geosciences (Beijing), Beijing 100083.{3. 3. Research Center of Science & technology Department, CNOOC, Beijing 100027,{3. 4. guangzhou Marine Geological Survey, Ministry of Land & Resources, guangzhou 510075,{3. 5. Ecole Polytechnique Montreal, H3.3.7, Canada 1. Key Laboratory of Marginal Sea Geology and Resources Chinese Academy of Sciences Guangzhou 510640 China 2. china University of Geosciences (Beijing) Beijing 100083 China 3. Research Center of Science & technology Department CNOOC Beijing 100027 China 4. guangzhou Marine Geological Survey Ministry of Land & Resources Guangzhou 510075 China 5. Ecole Polytechnique Montreal H3C3A7 Canada

Recent geophysical surveys and basin modeling suggest that the No.1 fault in the Ying- gehai basin (YGHB) is the seaward elongation of the Red River fault zone (RRFZ) in the South china Sea (SCS). The RRFZ, which separates the South china and Indochina block, extends first along the Yuedong fault, offshore of Vietnam, and then continues southward and breaks off into two branches: the Lupar fault and the Tinjia fault. The southern extension of the Lupar fault dies out beneath the NW Borneo while the Tinjia fault extends southeast and reaches the Brunei-Sabah area. According to the gravity and geomagnetic data, and the tectonic evolution of the basins, there are different evolution histories between the Wan’an basin (WAB) and the basins in the Nansha block. The Tinjia fault may be the boundary between the Balingian block and the Nansha block. Hence, the line linking the Yue- dong fault and the Tinjia fault, which both are continental margin faults and strike-slip ones in the geological evolution histories, constitute the boundary between the Indochina and Nansha block. The Lupar fault, in contrast, is an intraplate fault within the Indochina block. The results provide new hints for reconstructing the tectonic evolution history of the RRFZ and the opening of the SCS, and also a framework for hydrocarbon prospecting in the region.

关键词： Red River fault zone, tectonic evolution, fault, extension, western South china Sea.

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 Sciences, Qingdao 266071,{3. 2. Graduate School of the chinese academy of Sciences, Beijing 10003.,{3. 3. institute of Soil Science, chinese academy of Sciences, Nanjing 210008,{3. 4. institute of Geology and Geophysics, chinese academy of Sciences, Beijing 100029,{3. 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the chinese academy of Sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of Geology 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.