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Chinese Science Bulletin 2008年第24期53卷 3860-3865页

作者： CHEN Fang1,2 & DONG XiPing1,2 1 school of earth and space Sciences,{3. university,beijing 100871,china 2 Laboratory of Paleontology and Stratigraphy,Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nan-jing 210008,china peking Univ Sch Earth and Space Sci Beijing 100871 Peoples R China.

Countless fossil embryo Olivooides and the hatched larvae,juveniles and adults(the latter two kinds are Punctatus) are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section,near Kuanchuanpu Village,Ningqiang County,Shaanxi Province,*** the technique of Synchrotron X-ray Tomographic Microscopy,the 3. internal structure of Olivooides and Punctatus is *** morphological and statistic analyses are also given to the stellae structure of Olivooides and Punctatus,which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching,probably with the function of mucilage *** internal structure of Punctatus is described and *** ovum-like structure,a common internal feature of Punctatus,is considered as the taphonomic structure,rather than eggs or other biological *** structure is thought to be formed after the burial of the animal and before or during the *** original internal structure of Punctatus is assumed to be tabulae-filled,with soft body grown on them.

关键词：同步加速器 X射线显微镜寒武系化石动物区系内部结构

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

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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

Framework and development of digital china

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Science china(Technological Sciences) 2008年第S1期51卷 1-5页

作者： WU Lun & TONG QingXi Institute of Remote Sensing and Geographical Information Systems,peking university,beijing {3.,china Institute of Remote Sensing and Geographical Information Systems Peking University

Digital china (DC) has recently drawn much attention. It is a strategic project for china in response to the challenge of sustainable development of population,re-source,and environment. Intending to establish the national information infra-structure (NⅡ),the DC project forms a solid foundation for Chinese informatization. In such an NⅡ,multi-sourced spatial data are integrated. They focus on various themes and have different space and time features. Based on the NⅡ,numerous applications and services can be developed so that spatial information will benefit everyone. Since lots of organizations,such as governments,universities,and en-terprises,are involved in the implementation of DC,the DC project will significantly prompt the relevant scientific research as well as economic progress in china.

关键词： Digital earth Digital china spatial information sciences and technology

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,{3. 2. Graduate school of the Chinese Academy of Sciences, beijing 10003.,{3. 3. school of Geophysics and Geoinformation Systems,{3. university of Geosciences, beijing 100083.{3. SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate school of the Chinese Academy of Sciences Beijing China school of Geophysics and Geoinformation Systems China University of Geosciences 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.

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,{3. 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 11003.,china) school of earth and space Sciences Peking University Beijing 100871 China Institute of Geology and Geophysics and Key Laboratory of Mineral Resources Chinese Academy of Sciences 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

Frontal genesis of moisture atmosphere during the early 2008 persistent freezing-rain event in southern china

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Science china earth Sciences 2010年第3期53卷 454-464页

作者： QIAN WeiHong1 & FU JiaoLan1,2 1 Department of Atmospheric Sciences, school of Physics, peking university, beijing 100871,{3. 2 National Meteorological Center of CMA, beijing, 100081,{3. Department of Atmospheric Sciences School of Physics Peking University Beijing China National Meteorological Center of CMA Beijing China

From January 10 to February 2, 2008, a severe and persistent freezing-rain event occurred in southern and southwestern china. Here we use an observational analysis to compare the persistent freezing-rain event in the early 2008 with the winter precipita- tion in the late 2007 over south of the Yangtze River (Jiangnan). The persistent freezing-rain event was directly linked to the activity of quasi-stationary front. The gradient of equivalent temperature (ET) can well indicate the frontal genesis of moist atmosphere (moisture front) and its activity as well as its relationship with precipitation belt. The precipitation types (snow and freezing rains) are related to the vertical structure of moisture front. The inversion profile of ET vertical distribution is a typical synoptic condition that caused the freezing-rain event. The horizontal gradient of ET with a criterion of 10℃ / 100 km, which reflects the accumulation and release of atmospheric energy, can be applied to predict the precipitation 5-10 days in advance.

关键词： freezing-rain event frontal genesis extended-range weather forecast winter Jiangnan

An Early Cretaceous Avialian Bird, Shenzhouraptor sinensis from Western Liaoning, china

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 21-27页

作者： Ji Qiang, Ji Shu’an, You Hailu, Zhang Jianping,Zhang Hongbin, Zhang Nanjun, Yuan Chongxi and Ji XinxinDepartment of earth Sciences, Nanjing university, Nanjing, Jiangsu 100093.nstitute of Geology, Chinese Academy of Geological Sciences, beijing 10003. {3. of earth and space Sciences, peking university, beijing 100871china university of Geosciences, beijing 100083.11} Dinosaur Park of Changzhou, Changzhou, Jiangsu 213.02 Nanjing Univ Dept Earth Sci Nanjing 100093 Jiangsu Peoples R China Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China china Univ Geosci Beijing 100083 Peoples R China china Dinosaur Pk Changzhou Changzhou 213002 Jiangsu Peoples R China

This paper describes an avialian bird from the Early Cretaceous JiufotangFormation in Yixian county, western Liaoning china, which is named as Shenzhouraptor sinensis by Jiet al. on July 15, 2002. Shenzhouraptor sinensis is characterized by no teeth in its mouth, theforelimbs longer than the hindlimbs, a long tail with more than 23.caudal vertebrae, U-shapedwishbone, and remiges longer than the total length of ulna and manus. It is certain that the newavialian bird is really capable of powerful flight, representing a missing link between theropoddinosaurs and birds.

关键词： Avialian birds Early Cretaceous Jiufotang Formation western Liaoning china

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china earth Sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2, DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2 1. National Research Center of Geoanalysis, beijing 10003., china 2. Laboratory for earth Material Cycling, {3. of earth and space Sciences, university of Science and Technology of china, Hefei 23.026, china 3. Institute of Mineral Resource, Chinese Academy of Geological Sciences, beijing 10003., china National Research Center of Geoanalysis university of Science and Technology of china Chinese Academy of Geological Sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.279 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china earth Sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3.& PENG Jian4 1 school of Water Resource and Hydropower, Sichuan university, Chengdu 610065, china 2 National Satellite Meteorological Center, china Meteorological Administration, beijing 100081, china 3.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 4 school of Environmental Sciences, peking university, beijing 100871, china school of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China school of Environmental Sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

CONTACT PROCESS ON HEXAGONAL LATTICE

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Acta Mathematica Scientia 2010年第3期30卷 769-790页

作者：姚强李群昌 Department of Statistics and Actuarial Science School of Finance and Statistics East China Normal University school of Mathematical Sciences Peking University

In this article, we discuss several properties of the basic contact process on hexagonal lattice H, showing that it behaves quite similar to the process on d-dimensional lattice Zd in many aspects. Firstly, we construct a coupling between the contact process on hexagonal lattice and the oriented percolation, and prove an equivalent finite space-time condition for the survival of the process. Secondly, we show the complete convergence theorem and the polynomial growth hold for the contact process on hexagonal lattice. Finally, we prove exponential bounds in the supercritical case and exponential decay rates in the subcritical case of the process.

关键词： Hexagonal lattice contact process critical value complete convergence theorem rate of growth