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Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3 Li Zhitong~4 (1.school of earth and space sciences,peking university,beijing 100871,china 2.Institute of Geology and Geophysics and Key Laboratory of Mineral Resources,Chinese Academy of sciences,beijing 100029,china 3.Key Laboratory of Continental Dynamics,Northwestern university,Xi'an 710069,china 4.Institute of Geology and Mineral Resources of Shenyang,Shenyang 110032,china) school of earth and space sciences Peking University Beijing 100871 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Acad. of Sci. Beijing 100029 China Key Laboratory of Continental Dynamics Northwestern University Xi'an 710069 China Institute of Geology and Mineral Resources of Shenyang Shenyang 110032 China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

Simulation studies of high-latitude magnetospheric boundary dynamics

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Science china(Technological sciences) 2004年第4期47卷 421-435页

作者： PU Zuyin1, SHI Quanqi1,3, XIAO Chijie1, FU Suiyan1, ZHANG Hui1,2, ZONG Qiugang2 & LIU Zhenxing3 1. school of earth and space sciences, peking university, beijing 100871, china 2. Center for space Physics, Boston university, 725 Commonwealth Avenue, Boston, MA 02215, USA 3. Center for space Science and Application Research, Chinese Academy of sciences, beijing 100080, china school of earth and space sciences Peking University Beijing China Center for space Science and Application Research Chinese Academy of Sciences Beijing China Center for space Physics Boston University Boston USA

Magnetic reconnection at the high-latitude magnetopause is studied using 2.5-dimensional Hall-MHD simulation. Concentric flow vortices and magnetic islands appear when both Hall effect and sheared flow are considered. Plasma mixing across the magnetopause occurs in the presence of the flow vortices. Reconnected structure generated in the vicinity of the subsolar point changes its geometry with increasing flow shear while moving to high latitudes. In the presence of flow shear, with the Hall-MHD reconnection a higher reconnection rate than with the traditional MHD is obtained. The out-of-plane components of flow and magnetic field produced by the Hall current are redistributed under the action of the flow shear, which makes the plasma transport across the boundaries more complicated. The simulation results provide some help in understanding the dynamic processes at the high latitude magnetopause.

关键词： magnetopause, entry layer, magnetic reconnection, vortex reconnection, Hall effect, flow shear.

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Numerical study of the role played by magnetic reconnection in solar wind origin

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Numerical study of the role played by magnetic reconnection ...

A study of the microbial mineralization in submarine black smoker chimneys from the Okinawa Trough

第十四届全国日地空间物理学术研讨会

作者： L.P.Yang ( school of earth and space sciences, peking university, 100871 beijing, china )

Previous studies has suggested a new scenario to describe the solar wind origin, in which plasmas flowing upward and downward in the coronal funnel are the result of magnetic reconnection between the open funnel and adjacent closed loops driven by the supergranular advection. In this work, we try to investigate this scenario by carrying out numerical simulation in two dimensions. Using threshold and dependence of finite resistivity on macroscopic plasma parameters, we obtained the consequences of reconnection between low loops and funnel-shaped magnetic field driven by supergranular advection. The results successfully reproduce the plasma flowing upward to form the solar wind as well as the plasma flowing downward back to the lower atmosphere. Also, the results are compared with the observed signatures of plasma flowing in the coronal funnel.

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Acta Oceanologica Sinica 2009年第2期28卷 87-95页

作者： FENG Jun LI Jianghai CHU Fengyou National earthquake Response Support Service China Earthquake Adiministration Beijing 100049 China school of earth and space sciences Peking University Beijing 100871 China Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

Large amounts of microfossil records discovered in the seafloor black smoker chimney are reported from the Okinawa Trough. They are well preserved and can be divided into four types of filamentous microfossils. It suggests that the fossils may be derived from sulfur or iron oxidation chemolithotrophic prokaryotes and fungi. Based on the comparison studies of the microbial mineralization processes, two steps of biomineralization were hypothesized：（1） biology controlled mineralization; and （2） biology induced mineralization. At the early stage of the mineralization, the biology controlling mineralization is dominating; at the later stage, the biology inducing mineralization is the main mechanism. The composition of the fluids and the species of the microbes will determine the types of the minerals formed.

关键词： microfossils biomineralization black smoker Okinawa Trough

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A challenge to the concept of slip-lines in extrusion tectonics

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Geoscience Frontiers 2011年第1期2卷 23-34页

作者： Yadong Zheng~(a,*),Erchie Wang~b,Jinjiang Zhang~a,Tao Wang~c a Key Laboratory of Orogenic Belts and Crustal Evolution,Ministry of Education,school of earth and space sciences, peking university,beijing 100871,china b Institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100029,china c Institute of Geology,Chinese Academy of Geological sciences,beijing 100037,china Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Wide-open V-shaped conjugate strike-slip faults in Asia are typically related to extrusion ***,the tectonic model based on the slip-line theory of plasticity has some critical problems associated with *** conjugate sets of slip-lines in plane deformation,according to the theory of plasticity should be normal to each another but,in reality,the angles between the conjugate strike-slip faults,which are regarded as slip-lines in extrusion tectonics in the eastern Mediterranean,Tibet-middle Asia,china and the Indochina Peninsular regions,are always more than 90°(on average～110°) in the direction of contraction. Another problem is that the slip-line theory fails to explain how,in some cases,e.g.,in the Anatolian area in the eastern Mediterranean,the extrusion rate is much higher than the indent *** two major problems are easy to solve in terms of the Maximum-Effective-Moment(MEM) Criterion that predicts that orientations of the shear zones are theoretically at an angle of 54.7°and practically at angles of 55°±10°with theσ- or contractional *** orientations of the strike-slip faults that accommodate extrusion tectonics are,therefore, fundamentally controlled by the MEM *** extrusion is along the MEM-orientations,the extruding rate is normally higher than the indenting rate.

关键词： Extrusion tectonics Slip-line Wide-open V-shaped strike-slip faults MEM-Criterion Strain rate

TEMPORAL DISTRIBUTION AND PALEOGEOGRAPHICAL RADIATION OF PSITTACOSAURUS (DINOSAURIA:CERATOPSIA) IN EARLY CRETACEOUS OF EAST ASIA

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TEMPORAL DISTRIBUTION AND PALEOGEOGRAPHICAL RADIATION OF PSI...

Zhang-Xuan thermal uplift and its genesis

第二届国际古生物学大会

作者： Changfu ZHOU, Keqin GAO school of earth and space sciences, peking university, beijing 100871, china.

Psittacosaurus (parrot-beaked dinosaur) is a small, bipedal, basal ceratopsian, which is known only from the Early Cretaceous of East Asia. Since the first discovery in 1920s, there have been abundant fossils of Psittacosaurus found from the Early Cretaceous beds in Mongolia, western Siberia, and northern china. Most Psittacosaurus-bearing formations contain

关键词： Psittacosaurus paleogeographical radiation Early Cretaceous East Asia

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2, ZHANG Lüqiao3 and LI Hongyang2(1. school of earth and space sciences, peking university, beijing 100871, china 2. Shijiazhuang university of Economics, Shijiazhuang 050031, china 3. Geological Bureau of Inner Mongolia, Huhhot 010020, china) school of earth and space sciences Peking University Beijing 100871 China Shijiazhuang university of Economics Shijiazhuang 050031 China Geological Bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the Zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 130—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed Zhang-Xuan uplift toward its periphery. Combining the Zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North china Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North china during this period.

关键词： Zhang-Xuan area underplating thermal uplift fission track extensional structure.

A fluid inclusion study of Linglong Gold Deposit,Shandong,china

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A fluid inclusion study of Linglong Gold Deposit,Shandong,Ch...

Quasi-periodic outflows observed by the X-Ray Telescope onboard Hinode in the boundary of an active region

First Meeting Asia Current Research on Fluid Inclusion

作者： Zuqing Zhang, Yong Lai, Yanjing Chen school of earth and space sciences, peking university, beijing 100871, china

Linglong gold deposit is located in northwest of Shandong Peninsula, and is one of the most important super-large scale gold deposits in china. Fluid inclusion studies have been undertaken in order to characterize and understand the mineralizing fluids. Further more, X-type fluid inclusion planes were studied for realizing the relationship between fluid inclusion planes and tectonic events.

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Research in Astronomy and Astrophysics 2010年第12期10卷 1307-1314页

作者： Li-Jia Guo Hui Tian Jian-Sen He school of earth and space sciences Peking University Beijing 100871 China guolijia32 @ 163. com Max-Planck-Institut fur Sonnensystemforschung 37191 Katlenburg-Lindau Germany

Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature.

关键词： solar wind -- Sun: UV radiation -- active region

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