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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, china 2. Department of Atmospheric science, Yunnan{3., Kunming 650091, china 3. Graduate{3. of the Chinese Academy of sciences, Beijing 100049, china 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.

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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science china(Technological sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2 & FENG Xueshang1,3.1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space science and Applied Re-search, Chinese Academy of sciences, Beijing 100080, china 2. Graduate School of the Chinese Academy of sciences, Beijing 10003., china 3. School of Geophysics and Geoinformation Systems, china university of geosciences, Beijing 100083. china 1. SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. School of Geophysics and Geoinformation Systems China University of Geosciences 100083 Beijing China

Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3. The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 3.% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

Ladinian radiolarian fauna, siliceous rock from the Xianshuihe Belt, West Sichuan and their tectonic significance

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science china earth sciences 2005年第1期48卷 42-47页

作者： LIANG Bin, FENG Qinglai, WANG Quanwei, GUO Jianqiu, ZHONG Changhong & LI Zhenjiang Faculty of earth science, china university of geosciences,{3., china Sichuan Geological Survey, Chengdu 610000, china 1. Faculty of earth science China University of Geosciences 430074 Wuhan China 2. Sichuan Geological Survey 610000 Chengdu China

Ladinian radiolarian fauna, including Muelleritortis, Baumgartneria, Oertlispongus, Paroertlispongus, Pseudoertlispongus, etc., was discovered from the siliceous rock of the Runiange Formation in the Xianshuihe belt, West Sichuan Province. Geochemical test on five samples from the siliceous rock indicates that SiO2 content varies in 71.16%-90.06% and Si/Al ratio, in 49-71, which shows that the siliceous rock contains more terrigenous mud sediments. The siliceous rock is characterized by the large ratios of Al2O3.(Al2O3.Fe2O3. (0.63.0.81) and Ti/V (>26), the low ratio of V/Y (3.μg/g), which are similar to the geochemical characteristics of continental margin siliceous rock. The Ce/Ce* ratios of the four samples vary in 1.02-1.47 and the LaN/CeN ratio, in 0.75-1.07, which imply that the siliceous rock was deposited in the continental margin basin. But only one sample is similar to the oceanic siliceous rock in REE. Turbidite-siliceous rock bearing radiolarian-basalt assemblage and the geochemical characteristics of the siliceous rock indicate that the Xianshuihe belt is in the strong rift stage in the Ladinian age.

关键词： siliceous rock, radiolarians, Triassic, the Xianshuihe belt, West Sichuan.

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

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science china earth sciences 2011年第4期54卷 473-480页

作者： FANG JiaSong 1,2 &ZHANG Li 3.1 State Key Laboratory of Marine Geology,Tongji university,Shanghai 200092,china 2 College of Natural and Computational sciences,Hawaii Pacific university,Kaneohe,HI 96744,USA 3.tate Key Laboratory of Geological Processes and Mineral Resources,Faculty of earth sciences,china university of geosciences,wuhan 43.074,china 1. State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China2. College of Natural and Computational Sciences Hawaii Pacific University Kaneohe HI 96744 USA3. State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean *** oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine *** application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem *** we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.

关键词： microbial oceanography genomics metagenomics genes biomass bacteria archaea eukarya phylogeny physiology metabolism ecology biogeochemistry microbiology ecosystem function

Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

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science china earth sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2, DENG Chenglong1, ZHU Rixiang1 & XIE Fei3.1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sci- ences, Beijing 100029, china 2. School of the earth sciences and Resources,{3., Beijing 100083. china 3. Hebei Province Institute of Cultural Relics, Shijiazhuang 050000, china 1. Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. School of the earth sciences and Resources China University of Geosciences Beijing 100083 China 3. Hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3.and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

Numerical study of the auroral particle transport in the polar upper atmosphere

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science china(Technological sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3.1 School of Electronic Information, wuhan university, wuhan 43.079,{3. 2 Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, wuhan 43.079,{3. 3.School of earth and Space sciences, Peking university, Beijing 100871,{3. 1. School of Electronic Information Wuhan University Wuhan 430079 China 2. Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan 430079 China 3. School of earth and Space sciences Peking University Beijing 100871 China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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science china(Technological sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1,3. LIU Zhilin1, ZHANG Chengwei1,2 & ZHOU Yingchun1 1. Liaoning Institute of Technology, Jinzhou 121001, china 2. china National Oil and Gas Exploration and Development Corporation, Beijing 100011, china 3. College of{3., Northeastern university, Shengyang 110006, china 1. Liaoning Institute of Technology 121001 Jinzhou China 2. College of science Northeastern University 110006 Shengyang China 3. china National Oil and Gas Exploration and Development Corporation 100011 Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

Exploring the deep biosphere

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science china earth sciences 2011年第2期54卷 157-165页

作者： FANG JiaSong1,2 & ZHANG Li3.1 State Key Laboratory of Marine Geology, Tongji university, Shanghai 200092, china 2 College of Natural and Computational sciences, Hawaii Pacific university, Kaneohe, HI 96744, USA 3.State Key Laboratory of Geological Processes and Mineral Resources, Faculty of earth sciences, china university of geosciences, wuhan 43.074, china 1. State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China2. College of Natural and Computational Sciences Hawaii Pacific University Kaneohe HI 96744 USA3. State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Over the past two decades, scientific drilling into sediments and rocks in the ocean and the continent has revealed the presence of physiologically and phylogenetically complex microbial life in the deep subsurface. Microorganisms, most of which have no cultured or known relatives in the surface biosphere, have been discovered in sediments and rock at depth as deep as 1 km below the seafloor and more than 3.km deep in the continent. The deep biosphere probably represents the most voluminous part of the global biosphere and may constitute as much as 50% of the earth’s biomass. In this article, we review the current knowledge of and most recent advances in studying the deep biosphere and suggest directions in future research.

关键词： deep biosphere Thomas Gold microorganism biomass DNA ribosome ODP CARD-FISH dark energy lipids serpentinization

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, china 2 Center for Materials Analysis, Nanjing university, Nanjing 210093. china 3. Department of{3. sciences, Nanjing university, Nanjing 210093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China Department of earth sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

EPR studies of Mn^(2+) in the Loess Plateau of central china: Implication for variation of the East Asia summer monsoon

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Chinese science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2 and LU Huayu\+3.. Department of earth sciences, Nanjing university, Nanjing 210093.{3. 2. Center of Material Analysis, Nanjing university, Nanjing 210093.{3. 3. Xi’an Laboratory of Loess and Qu Department of earth sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2+