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Journal of earth Science 1998年第2期17卷 8-16页

作者： Ling Wenli Gao Shan Cheng Jianping Zhang Benren Faculty of earth sciences, china university of Geosciences, Wuhan 430074 Zheng Haifei Department of Geology, peking university, beijing 100871

This paper reports the systematic studies of geochemistry on the meta sedimentary rocks, felsic gneisses and amphibolites of the Kongling complex from the Archean high grade terrain of the Yangtze craton. It shows that the amphibolites originated from a weakly depleted mantle resource. Nb negative anomaly, negative ε (Nd, t ) and the t DM ages which older than their isochron ages of the TTG gneisses imply the possible existence of the crust older than round about 2.7 Ga in the region. Three types of meta sedimentary rocks are identified from the Kongling complex. The first type originated from the juvenile crust with the features of the first cycle sedimentary rocks. Cratonic sedimentary rocks characterize the second type. Mobilization of REE and other elements resulted from partial melting during the migmatization is found in the third type of meta sedimentary rocks. Apart from the early TTG gneisses, some of the mafic rocks are also expected to be the source rocks of the first type of para rocks. The deposition times of the first and second type paragneisses are closed in the Neoarchean of about 2.7 Ga and the early period of Proterozoic respectively, and the period when cratonization of the Yangtze continental block completed is referred to be earlier than the Mesoproterozoic. Nd isotopic tracing on the magma sources of the Jinning granitic rocks in the region reveals that the major part of the Kongling basement is Neoarchean.

关键词： Archean high grade terrain Kongling complex geochemical characteristics tectonic setting cratonization.

Steady motion and spiral patterns in typhoon

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Acta Oceanologica Sinica 1999年第4期18卷 495-504页

作者： Liu Shikuo Liang Fuming Liu Shida and Xin Guojun (Department of Geophysics, peking university, beijing 100871, china) Department of Geophysics Peking University Beijing 100871 China

By using the equations describing typhoons in the atmosphere, the steady three-dimensional stream fieldand the corresponding pressure and temperature fields are obtained. The three-dimensional velocity fields construct anonlinear autonomuos system in the physical space. It is shown that the center of typhoon is a local minimum pressurewith positive vertical vorticity and horizontal convergence in lower levels and a local maximum pressure with negativevertical vorticity and horizontal divergence in the upper levels. Because there exits two saddle-focus points in the autnomous system, there exist the spiral patterns, in which the winds blow spirally in and out of the center in the lowerand upper levels in the Northern Hemisphere and cause the ascending motion near the center and dascending motionnear the edge, respectively . All these are in fair conformity with the observations. It implies that the rotation of earthand the viscosity of air play an important role in the spiral structure of typhoons.

关键词： Typhoon steady motion spiral pattern

Pleonaste in Boxian meteorite

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Chinese Science Bulletin 1998年第19期43卷 1656-1660页

作者： WANG Kuiren and HONG Ji’an Department of earth and space sciences, university of Science and Technology of china Advanced Research Center for earth sciences and Astronomy, university of Science and Technology of china, Third World Academy of sciences Department of earth and space sciences University of Science and Technology of China China Advanced Research Center for earth sciences and Astronomy University of Science and Technology of China Third World Academy of Sciences Hefei China

There are three kinds of occurrence of pleonaste, a rare meteoritic mineral, totally found in Boxian meteorite. They are as the following: (ⅰ) occurring in the inner circle of the chondrule edge, of which a circle texture is composed; (ⅱ) occurring in the state of inclusions, included in an olivine chondrule, with close paragenesis of wadsleyite; (ⅲ) occurring in the state of porphyry. The chondrule in the first occurrence belongs to CA chondrules. The chemical compositions of pleonaste are heterogeneity except for the atomic ratios of Fe/(Mg+Fe), which can be attributed to the following reasons: (ⅰ) they are congenetic minerals; (ⅱ) the heterogeneity of the compositions of the solar clouds in the early states; (ⅲ) the chondrites are the multiple-stage evolution; (ⅳ) the further proof of Boxian meteorite is an unequilibrium common chondrite.

关键词： rare pleonaste in meteorites found genesis.

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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Science china earth sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2 1.Institute of Remote Sensing and GIS of peking university,beijing 100871,china 2.Center of Remote Sensing and GIS of beijing Normal university,beijing 100875,china 1. Institute of Remote Sensing and GIS of peking university 100871 Beijing China 2. Center of Remote Sensing and GIS of beijing Normal university 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.

Mantle xenoliths from Late Cretaceous basalt in eastern Shandong Province: New constraint on the timing of lithospheric thinning in eastern china

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Chinese Science Bulletin 2003年第19期48卷 2139-2144页

作者： YAN Jun, CHEN Jiangfeng, XIE Zhi & ZHOU Taixi School of earth and space sciences, university of Science and Technology of china, Hefei 230026, china Yarmouk university Irbid - Jordan School of earth and space sciences University of Science and Technology of China Hefei 230026 China

The age of the alkali basalt from Daxizhuang in Jiaozhou, eastern Shandong, was determined to be 73.5±0.3 Ma by 40Ar-39Ar technique. The basalt gave high eNd(t) values of +7.5 and +7.6, suggesting that the primitive magma was derived from depleted asthenospheric mantle with a formation depth of about 65—95 km. Spinel-lherzolite xenoliths have been discovered in the basalt. The Fo values of olivine from the xenoliths range from 88 to 89. The estimated equilibrium P-T conditions of spinel-lherzolite xenoliths are about 2.0 GPa and 1010—1140℃, suggesting an equilibrium depth of about 65 km. Geochemical characteristics of the Late Mesozoic (125—115 Ma) mantle-derived rocks in Shandong Province suggest an enriched lithospheric mantle along the southern margin of the North china block. However, geochemical characteristics of the Late Cretaceous basalts in Daxizhuang and the equilibrium P-T condition estimated from the xenoliths suggest that the lithosphere at 73 Ma ago was as thick as that of the Cenozoic in the region. Additionally, the xenoliths are rich in basaltic-component, suggesting a derivation from a newly-formed lithosphere. Therefor, lithospheric thinning took place at a time interval between about 120 and 73 Ma along the southern margin of the North china block.

关键词：覆盖捕虏岩白垩纪玄武岩山东东部地区岩石圈稀释化 ^40Ar-^39Ar技术

“Tali Glaciation” on Massif Diancang

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Science china earth sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3 & YANG LiRong3 1 Institute of Tibetan Plateau Research, Chinese Academy of sciences, beijing 100085, china 2 College of Environmental sciences, peking university, beijing 100871, china 3 Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, china 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. College of Environmental sciences Peking University Beijing 100871 China 3. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 30—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3600 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

Zhang-Xuan thermal uplift and its genesis

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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 13.—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.

Extremal Quasiconformal Mappings Compatible with Fuchsian Groups

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Acta Mathematica Sinica,English Series 1996年第3期12卷 285-291页

作者： Shen Yuliang, Department of Mathematics peking university beijing, 100871 chinaPresent address: Department of Mathematics Suzhou university Suzhou, 215006 china Department of Mathematics Peking University Beijing China

For every torsion free Fuchsian group F with Poincaré’s -operator norm ║г║=1, it is proved that there exists an extremal Beltrami differential of F which is also extremal under its own boundary correspondence. It is also proved that the imbedding of the Teichmüller space T(Γ) into the universal Teichmüller space T is not a global isometry unless Γ is an elementary group.

关键词： Extremal quasiconformal mapping Extremal Beltrami differential Fuchsian group Poincaré operater

Diagenesis and Porosity of the Cambrian-Ordovician Carbonate Shoal Fades at Yangjiaping, Shimen, Hunan

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Acta Geologica Sinica(English Edition) 2000年第1期74卷 29-45,116-117页

作者： ZHANG Xiulian, WANG Yinghua and CHEN Xiaolong Department of Geology, peking university, beijing 100871 peking Univ Dept Geol Beijing 100871 Peoples R China

Upper Cambrian-Lower Ordovician shoal-facies carbonate rocks are well developed in the Yangjiap-ing section, Shimen, Hunan, and their types are also highly varied. There are both monomictic shoal-facies rocks (e.g. sparite oolitic limestone and sparite calcarenite) and polymictic shoal-facies rocks (e.g. grainstone, whose grain types include sand- and pebble-sized fragments, bioclasts, oolites, algal mats etc.). What is different is that the Upper Cambrian shoal-facies rocks have been mostly strongly dolomitized into shoal-facies dolomite with various residual textures. This paper presents an in-depth study of various kinds of diagenesis and pore space evolution occurring in this section and suggests that the diagenetic sequences of shoal-facies rocks in the study area is dominantly of retrogressive type.

关键词： rock types dolomitization dissolution diagenetic sequence

“Einstein Moon”,“Schrdinger Cat”,and “Quantity in Phase space”—About Quantum Measurement(Ⅰ)

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Communications in Theoretical Physics 2004年第6期 833-836页

作者： REN De-Ming Department of Physics,peking university,beijing 100871,china DepartmentofPhysics PekingUniversityBeijing100871China

Generalizing the idea involved in a previous paper [***.(beijing,china) 41 (2004)685],"quantity in phase space" is *** starting from quantum mechanics,with standard criteria,thedisappearing of interference in a macroscopic system is explicitly *** the confusions involved in "the EinsteinMoon" and "the Schrdinger Cat" are clarified,at least principally.

关键词： quantum measurement quantum communication