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中国科学院地质与地球物理研究所2002学术年会

作者： Z.Li~a,J.Y.Ping~b,M.Z.Jin~c,M.L.Liu~c a.Institute of geology and geophysics,Chinese Academy of Science,Beijing 100029,China b.department of Materials Physics,University of Science and Technology Beijing,Beijing 100083,China c.Instrumental Analysis Center,Jilin University,Changchun,Jilin Province,130023,China

The M(o|¨)ssbauer spectra of two chromites at 298 K and one chromite at 298 K,200 K, 170 K,14. K and 90 K were measured in this ***-based QSD method was used to analyze the *** tetrahedral site Fe and the octahedral site Fe quadrupole splitting distributions (QSDs) were obtained from the M(o|¨)ssbauer spectra of the chromites,and the large Gaussian widthsσof Gaussian components of tetrahedral site Fe QSDs for chromites were attributed to next nearest neighbor *** addition,temperature dependence of isomer shift and quadrupole splitting was *** between the Mossbauer parameters for thickness corrected spectra and raw folded spectra of chromites was made,and the results show that there are no significant difference between two sets of the Mossbauer *** is because of small absorber thickness of chromites in this *** between the M(o|¨)ssbauer parameters of chromites obtained using Viogt-base QDS method and Lorentzian doublet method was also made. The results show that much large x and lower Fe/(Fe + Fe) values were obtained when Lorentzian doublet method was used to fit the spectra of *** indicates that Voigt-based QSD method is adequate one being used to analyze the Mossbauer spectra of chromites.

关键词： Chromite Quadrupole Splitting Distributions Next nearest effects

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Simulation of the impact of the South to North Water Transfer Project on groundwater in the Beijing plain

Simulation of the impact of the South to North Water Transfe...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： YANG YONG~1,LI GUO-MIN~1,DONG YAN-HUI~1,LI MING~1, YANG JIANG-QING~2,ZHOU DONG~3 & YANG ZHONG-SHAN~3 1 Institute of geology and geophysics Chinese Academy of sciences,Beijing 100029,China 2 Ministry of Water Resources,department of Hydrological Analysis,Beijing 100053,China 3 Beijing Hydraulic Center,Beijing 100039,China

In the Beijing plain,the groundwater level has been gradually descending due to extensive groundwater pumping in consecutive drought *** the implementation of the South to North Water Transfer Project, an opportunity has been provided for restoration of groundwater under over-exploitation *** the basis of hydrogeology conditions of the Beijing plain,as well as the high performance parallel computing platforms,a numerical groundwater flow model was *** results show that several obvious depression cones of groundwater have been formed because of the rapid decline of groundwater levels in the Beijing plain in recent years. After the implementation of the South to North Water Transfer Project and due to the restrictions on groundwater exploitation,the area of the cone of depression will be reduced to different degrees,and the centre level of depression cone will rise *** is a benefit to relieve water shortage and control the development of land subsidence and the deterioration of the ecological environment.

关键词： South to North Water Transfer Project groundwater dynamic change Beijing plain numerical model parallel computing

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Transitions among Mariana-,Japan-,Cordillera-and Alaska-type are systems and their final juxtapositions leading to accretionary and collisional orogenesis

Transitions among Mariana-,Japan-,Cordillera-and Alaska-type...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： WENJIAO XIAO~(1*),CHUNMING HAN~1,CHAO YUAN~2,MIN SUN~3, GUOCHUN ZHAO~3 & YEHUA SHAN~2 1 State Key Laboratory of Lithospheric Evolution,Institute of geology and geophysics, Chinese Academy of Sciences,Beijing 100029,China 2 Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 51064.,China 3 department of Earth Sciences,The University of Hong Kong,Hong Kong,China

’Arc system’ is used here as a collective term for a variety of arcs that occur along continental margins or in oceanic plates;it includes associated units from adjacent *** major arc systems(Mariana-,Japan-,Cordillera-and Alaska-type)can be distinguished along the Circum-Pacific *** Japan-type arc systems in ancient orogens(*** Altaids) may have been largely regarded as microcontinents because they have so-called Precambrian basement. Often the Cordillera-type arc systems can be very complicated,and if they are rifted away from the host continent they become more difficult to *** these arc systems interact mutually and with continental marginal sequences,leading to complicated accretionary and colhsional *** alternation between Western Pacific archipelagos and the Eastern Pacific active margin is the stereotype of accretionary and colhsional *** importantly, these four main types of arc systems can be juxtaposed into a final orogenic collage, which is another main expression of accretionary *** some parts of accretionary and colhsional orogens can be terminated by attachment of a continent-size craton such as Tarim or even India,and even so the accretionary and colhsional processes may continue elsewhere along *** significance of the interactions among these arc systems and their final juxtaposition has not been fully appreciated in ancient *** Altaids together with the Circum-Pacific orogens offers a good opportunity to study such accretionary-collisional orogenesis.

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Rare earth elements of aeolian deposits in Northern China and their implications for determining the provenance of dust storms in Beijing

Rare earth elements of aeolian deposits in Northern China an...

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中国科学院地质与地球物理研究所2007学术年会

作者： Xiaoping Yang~(a,*),Yongsheng Liu~(a,1),Chaozhu Li~(a,2), Yuling Song~b,Heping Zhu~a,Xindi Jin~a a Institute of geology and geophysics,Chinese Academy of Sciences,Beijing,China b department of Physics and Information Technology,Ningxia Normal College,Guyuan,China 1 Present affiliation:China Institute of Geoenvironment Monitoring, Beijing. 2 Present affiliation:Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing.

This paper contributes to a better understanding of the source of dust storms in northern China and the relationship between these sources and other aeolian sediments in this *** samples in potential source areas were collected from the Hunshandake Sandy Land,Heaven Desert,the loess deposits of the Bashang area,the mountainous basins and valleys north of Beijing and from the Badain Jaran Desert and Hulunbaier Sandy Land(Fig.1).Dust samples were collected in Beijing during two dust storms in March 2002 and April *** laboratory methods used in this study included measurements of abundance of trace elements,in particular the rare earth elements(REEs),mineral assemblages and grain *** REE contents,Eu and Ce anomalies show clear differences between various *** is considered to be the key factor influencing REE patterns in the study *** REE abundances and patterns indicate that the aeolian sand north of Beijing,such as in the Heaven Desert, is mainly of local origin rather than from desert encroachment from the *** mineral grains carried in dust storms,however, are highly mixed,and may come partly from local sources but mainly from distant desert regions in western China.

关键词： Sandy land Dust storm Rare earth element(REE) Loess Northern China

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Addressing severe slope failure hazards along Sichuan-Tibet Highway in Southwestern China

Addressing severe slope failure hazards along Sichuan-Tibet ...

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中国科学院地质与地球物理研究所2003学术年会

作者： Shang Yanjun~1,Yue Zhongqi~2,Yang Zhifa~1,Wang Yangchun~3,and Liu Da’an~1 1.Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100029,China, 2.department of Civil Engineering,The University of Hong Kong,Hong Kong,China 3.Institute of Mountain Hazards and Environment,Chinese Academy of Sciences & Water Conservancy Ministry,Chengdu 61004.,China

This paper presents the results of recent field investigations on the geological hazards along the Sichuan-Tibet Highway in Southwestern *** was found that one section of the highway has been facing severe problems in slope *** is the section between Linzhi and Basu and it has been the most dangerous part of the highway system to road users over the last fifty years. Based on the examination of structural geology,Quaternary geology,stratigraphy and petrography,this paper presents the classification,distribution and hazard levels of the slope failures along the highway section. The failures usually occurred in slopes comprising Quaternary glacial deposits,fluvio-lacustrine deposits and residual *** can be classified as landslides, mud-rock flows,grain flows on slopes and rock *** are caused by four main factors:a) intense active tectonic movements,b) on-going alpine canyon relief,c) heavy precipitation and d) irrational human *** paper further discusses the engineering measures adopted by the relevant organizations over the past fifty *** on the investigations,the paper summarizes some useful recommendations to effectively address and mitigate the severe slope failure hazard problem for safe operation of the highway and future railway systems.

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Research Advances on the Loess-Bedrock Landslide in China

Research Advances on the Loess-Bedrock Landslide in China

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2012 Asia Pacific Conference on Environmental Science and Technology(APEST 2012)

作者： Chengyi Fan1 a Shouyun Liang1 b and Xiangxian Ma2 c 1 Key Laboratory of Mechanics on Disaster and Environment in Western China the Ministry of Education of China and department of Geological Engineering College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 P.R.China 2 Key Laboratory of Petroleum Resources Research Institute of geology and geophysics Chinese Academy of Sciences Lanzhou 730000 P.R.China

Loess landslide is one of the serious geological disasters in and around the loess plateau in northwest of *** the major type of loess landslide in this area,loess-bedrock landslide widely distributes,frequently occurs,and causes serious casualties and property *** the formation mechanism and protection countermeasures arousing increasingly,the scientists have paid close attention and got a series of research *** is very important of systematic summary and thorough analysis of the loess-bedrock landslide for reducing disasters caused by loess *** acquired achievements of the loess-bedrock landslide have been summarized on classification,formation mechanism,influencing factors and hazard range,and some main fields are put forward for further researching:（1） to explore the control action and boundary effect of paleo-weathering crust upon the top of bedrock for the loess-bedrock landslide;（2） to research the influence of the orientation and the top fluctuant configuration of bedrock and the slope structure on loess landslide;（3） to study the relationship between the landslide formation and the slope profile structure,the physical,hydrological and mechanical properties of the rock-soil mass;（4. to research the critical value of locked segment in the loess-bedrock cutting layer landslide;（5） to analyze the main influencing factors and forecast the hazard range of different types of the loess-bedrock landslide.

关键词： Loess-bedrock landslide Landslide classification Formation mechanism Hazard range Research advances.

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太阳周围的慢激波与Alfvén起伏通过它的变化

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Chinese Journal of Astronomy and Astrophysics 1984年第4期 294-303页

作者：魏奉思涂传诒中国科学院空间物理所北京大学地球物理系

本文处理了阿尔文(Alfven)起伏通过磁流体慢激波的变化.在阿尔文起伏源于太阳和太阳周围(2—6R)可能存在驻慢激波的前提下,分析了阿尔文起伏通过太阳周围的慢激波的情形,结果表明:(1)中性片附近低纬区是阿尔文起伏可以无条件通过的(或小... 详细信息

本文处理了阿尔文(Alfven)起伏通过磁流体慢激波的变化.在阿尔文起伏源于太阳和太阳周围(2—6R)可能存在驻慢激波的前提下,分析了阿尔文起伏通过太阳周围的慢激波的情形,结果表明:(1)中性片附近低纬区是阿尔文起伏可以无条件通过的(或小)畸变区;(2)远离中性片高纬区只是低阿尔文马赫数时(M 0.3)的小畸变区;(3)阿尔文起伏源于太阳、太阳周围可能存在慢激波与空间观测到阿尔文起伏这三者是相容的,从而为太阳周围可能存在慢激波这一假设提供了一种间接支持.

关键词：慢激波磁流体力学激波阿尔文 Alfv 中性片太阳恒星周围

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Fragments of hot and metasomatized mantle lithosphere in Middle Miocene ultrapotassic lavas,southern Tibet

Fragments of hot and metasomatized mantle lithosphere in Mid...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Chuan-Zhou Liu~(1*),Fu-Yuan Wu~1,Sun-Lin Chung~2,and Zhi-Dan Zhao~3 1 State Key Laboratory of Lithospheric Evolution,Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 department of Geosciences,National Taiwan University,Taipei 10699,Taiwan 3 State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China

Uplift of the Tibetan Plateau and its influence on our global climate have been the focus of numerous *** potassic to ultrapotassic volcanism is widespread in southern Tibet and has been generally attributed to convective removal of collision-thickened Asian lithosphere,which is also responsible for the uplift of the *** implicit assumption of this model is the existence of a hydrous,metasomatized(i.e.,phlogopite bearing) lithospheric mantle that remained after the convective thinning and was subsequently heated to form small-volume *** such a lithospheric mantle was present in the Miocene,it implies further change since that time,as seismic velocities indicate that cold and strong upper mantle occurs beneath the thick crust in southern *** we describe peridotite xenoliths entrained in Middle Miocene ultrapotassic lavas from Sailipu,southern *** results suggest the existence of hot,highly metasomatized lithospheric mantle beneath southern Tibet during the Middle Miocene,and thus support the idea that convective thinning of the lithosphere was responsible for the uplift of the *** relict mantle was later removed or squeezed northward by the underthrusting Indian continental lithosphere,which terminated magmatism in southern Tibet and played a role in creating the entire plateau.

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Speciation and fractionation of rare earth elements in a Lateritic profile from southern China:Identification of the carriers of Ce anomalies

Speciation and fractionation of rare earth elements in a Lat...

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中国科学院地质与地球物理研究所2002学术年会

作者： Ying-Jun Ma~a Run-Ke Huo~b Cong-Qiang Liu~c a.Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100101,China b.Xi’an University of Technology,Xi’an 71004.,China c.Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002,China

The mobilization of rare earth elements(REE) during weathering has been well ***,there are still few studies of REE speciation in weathering profiles. Furthermore,ambiguities remain concerning the carriers of Ce *** study is to investigate the form and distribution of REE during weathering and identify the carriers of Ce anomalies.A sequential extraction procedure has been carried out on weathered samples from a 25m thick granitic profile in South *** phases were selected for extraction: adsorbed-exchangeable REE,bound to carbonates,bound to iron and manganese oxides;bound to organics,and *** rock chemical data show that the REE have been fractionated during *** are leached from the top zones and extremely enriched in the middle of the *** from the bottom to top of the profile HREE become more and more depleted,and LREE/HREE ratios obviously *** is fractionated from the other LREE:strong positive Ce anomalies are presented in the oxidized soil *** this profile the most important carrier of REE is exchangeable *** 4.-90%of the total REE is exchangeable,and even up to 95%at 10-11 m.10-30%of REE is bound to Fe-mn oxides,and in the oxidized soil zone up to 35%.Similarly,in the upper zone 10-25%of REE is linked to organics,and even up to 30%in the *** the upper soil zone the normalized REE patterns of the exchangeable fraction present positive Ce anomalies and LREE enrichment relative to fresh rock,and more than 50%of Ce is exchangeable in the clayey zone,implying clay is an important carrier of Ce *** REE patterns in Fe-mn oxides show strong positive Ce anomalies,and in the oxidized soil zone up to 70%of total Ce is bound to Fe-mn ***,the normalized REE patterns in organic fractions present strong positive Ce anomalies,and in the humus-layer Ce/Ce is up to 100,which suggests that organic matter plays an important role in the retention of *** is con

关键词： rare earth elements(REE) speciation chemical weathering Ce anomalies

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Quantum Symmetry for a System with a Singular Lagrangian Containing Subsidiary Condition

Quantum Symmetry for a System with a Singular Lagrangian Con...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Y.Zhang·J.H.Jiang·Z.P.Li·A.M.Du·X.H.Zhao Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100029,China department of Applied Physics,Beijing Polytechnic University,Beijing,China SIGMA Weather Group,State Key Laboratory of Space Weather,Center for Space Science and Applied Research,Chinese Academy of Sciences,P.O.Box 8701,Beijing 100190,China

The quantization for a system with a singular Lagrangian containing subsidiary constrained conditions in configuration space is *** system is called constrained singular *** certain case,the constrained singular system can be brought into the theoretical framework of the constrained Hamilton system.A modified Dirac-Bergmann algorithm for the calculation of constraints in the system is *** path integral quantization is formulated by using the Faddeev-Senjanovic scheme,and the classical/quantum Noether theorem in canonical formalism are also established for such a *** application of the results to study the fractional spin in non-Abelian Chern-Simons theory is *** make a precise investigation of the fractional spin for such a system at the quantal level.A simple example is presented to show that the connection between the symmetry and conservation law in classical theories in general is no longer preserved in quantum theories.

关键词： Lagrangian and Hamiltonian approach Symmetry and conservation laws Gauge field theories

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