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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china earth {2. 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4 1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., china 2. Institute of Geophysics, china Seismological Bureau, Beijing 100085, china 3. Institute of Deposition Resource, Chinese Academy of geosciences, Beijing 100037, china 4. school of Exploration and Information, china university of geosciences, Beijing 100083. china 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. school of Exploration and Information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2.km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2.segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

Compressive fracture characteristics of Zr-based bulk metallic glass

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 823-827页

作者： FAN ZhenJun,ZHENG ZhiYuan & JIAO ZengBao school of Materials sciences and Technology,{2. university of geosciences,Beijing 100083.{2. 1. school of Materials sciences and Technology China University of Geosciences Beijing 100083 China

The compressive fracture characteristics of Zr-based bulk metallic glass under uniaxial compression tests are *** zigzag rheological behavior is observed in the compression stress-strain curves of amorphous *** room temperature the uniaxial compression fracture takes place along the plane which is at a 45-degree angle to the direction of the compressive *** microstructure of a typical fracture pattern is the vein network.A unique,finger-like vein pattern is found to exist at the fracture surface of Zr-based bulk metallic glass.

关键词： bulk metallic glass fracture surface compressive fracture

Basic Lithofacies-Succession Model for the Wumishan Cyclothems: Their Markov Chain Analysis and Regularly Vertical Stacking Patterns in the Third-Order Sequences

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 421-431页

作者： MEI Mingxiang, MA Yongsheng and GUO Qingyin Institute of earth sciences and Natural {2., china university of geosciences, Beijing 100083.china Petrochemical Corporation (SINOPEC), Beijing 10002. Institute of earth sciences and Natural {2. China University of Geosciences Beijing 100083 china Petrochemical Corporation (SINOPEC) Beijing 100029 [?]3Mei Mingxiang Male born in 1965 got his Ph.D. in geology at the china university of geosciences in 1993. He has been engaged in sedimentology and stratigraphy and is now serving as an associate professor in the China University of Geosciences.

The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3300-m-thick carbonate strata formed in a period of about 100 Ma (13.0±2. Ma-12.7±10 Ma). In this succession of strata, the carbonate metre-scale cyclic sequences belonging to peritidal type with an approximately symmetrical lithofacies-succession are best developed. The wide development of 1:4 stacking patterns shows that these metre-scale cyclic sequences are genetically related to the short-eccentricity cycles, which are called the Wumishan cyclothems that could truly represent sedimentary cycles. Generally, massive and thick-bedded calcareous dolomites and dolomitic limestones of stromatolite biostromes and thrombolite bioherms constitute the central part of the Wumishan cyclothems. The lower and upper parts consist of tidal flat dolostones, sandy-muddy dolostone and the top part is composed of lagoonal facies dolomitic shales with a paleosol cap. Therefore, an approximately symmetrical lithofacies-succession is formed. Many features such as the clear deepening and shoaling vectors of cyclothems, and all kinds of marks of fresh-water diagenesis indicate that the Wumishan cyclothems are the product of autocyclic sedimentation governed by allocyclic high-frequency sea-level changes. The results of a Markov chain analysis reaffirm the existence of the lithofacies-succession model of the Wumishan cyclothems. The boundaries of the Wumishan cyclothems are marked by the instantaneous exposed punctuated surface, which leads to the discrepancy between the cyclothems and the parasequences of the sequence stratigraphy terminology system. It is difficult to form a judgment that the time span of the Milankovitch cycles in the Precambrian is certainly equal to that of the Phanerozoic, but the regularly vertical stacking patterns of the seventh-order rhythms, sixth-order cyclothems and fifth-order parasequence sets still indicate their consistency with the duration of the Milankovitch cy

关键词： Wumishan cyclothems Markov chain analysis Mesoproterozoic Jixian section Tianjin

Zircon geochronology and geochemistry of mafic xenoliths from Liaoning kimberlites:Track the early evolution of the lower crust,North china Craton

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Science china earth {2. 2004年第11期47卷 961-972页

作者： ZHENG Jianping1,YU Chunmei1,LU Fengxiang1 & LI Huimin2.1.Faculty of earth sciences,{2. university of geosciences,Wuhan 430074,{2. 2.Tianjin Institute of Geology and Mineral resources,Tianjin 300170,{2. 1. Faculty of earth sciences China University of Geosciences 430074 Wuhan China 2. Tianjin Institute of Geology and Mineral resources 300170 Tianjin China

Mafic xenoliths from Paleozoic Fuxian kimberlites (Liaoning Province) mainly in- clude garnet granulite, with minor pyroxene amphibolite, meta-gabbro and pyroxene syenite. The SiO2.contents of the xenoliths are from 47.3 wt% to 49.9 wt%. The granulites are mainly coarse-medium grained and reasonably with well-developed granoblastic (mostly polygonal) texture, contain the assemblage of garnet + plagioclase + pyroxene + K-feldspar ±phlogopite. The mineral assemblage of the amphibolites is plagioclase + pyroxene + amphibole ±K-feldspar, with the equilibrium temperature and pressure conditions of 744—82.℃ and 0.76—0.88 GPa. The granulites are regarded as derivation from the lower crust depth (more than 2. km), below the amphibolites. Garnet granulites compositionally correspond to sub-alkalic basalt, and have wide ranges of Ni abundance (13.—840 ppm), and Nb/Y (0.12.1.85), Nb/U (3.51—53.86) and Ta/U (0.38—2.48). The amphibolite and the syenite correspond to alkalic basalt. The Fuxian ma- fic xenoliths are regarded as the metamorphic product of the underplated magmas (including fractional crystallization or not) experienced the contamination with the pre-existed crustal com- ponents, and partly effected by kimberlitic magmas. The concordant ages of zircons for the gab- bro (2.10—2.80 Ma) and the near-concordant upper intercept ages of zircons for the garnet granulite and pyroxene amphibolite (2.78—2.38 Ma) indicate that they are currently known as the oldest deep-seated xenoliths from the lower crust of the North china Craton. These ages recorded the formation of the united Eastern Block of the North china Craton, That is, Neoar- chean (2.6—2.5 Ga) is an important continental crustal growth period of the North china Craton. The lower intercept age of the garnet granulite (1853 Ma) recorded an important tectonic thermal event in Paleoproterozoic. This event was probably related to collision of the East and West block, and resulted in the final assembly of the North china

关键词： mafic xenolith, petrochemistry, zircon geochronology, petrogenesis, lower crustal evolution, North china Craton.

The Construction of Natural Disaster Database of Alxa and Periodicity Analysis

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地学前缘 2009年第S1期16卷 300-301页

作者： Yan Zheng,Mingzhong Tian,Siwen Liu,Chao Ma school of the earth {2. and resources,china university of geosciences(Beijing),Beijing 100083.china.

A compilation of all meaningful historical data of natural-disasters taken place in Alxa of inner-Mongolia is used here for the construction of a 65 Ma high precision *** data in the database are divided into subsets ... 详细信息

关键词： Alxa natural disaster databases periodicity

Adjoint method for the optimum planning of industrial pollutant sources

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Science china earth {2. 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental sciences, Peking university, Beijing 100871, {2. 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., {2. 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Low temperature albitization in Caino-Mesozoic reservoir sandstones from North Tarim, and a discussion on the fluid origin

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Chinese Science Bulletin 1999年第S2期44卷 35-37页

作者： YE Ying~1, HU Shouxi~2.and SUN Jinggui~2.1. Department of earth sciences, Zhejiang {2., Hangzhou 31002., china 2. Department of earth sciences, Nanjing {2., Nanjing 2.0008, china Department of earth sciences Zhejiang University Hangzhou 310027 China Department of earth sciences Nanjing University Nanjing 210008 China

CAJNOZOIC and Mesozoic in North Tarim are predominantly a set of terrestrial detrital formations. In thereservoir sandstones in the area, albite is one of the widely developed authigenic mineral. Micro-structural evidence shows that diagenetic albite occurs as euhedral crystals in the pore, and replaces feldsparand other detritus along cleavage and micro-crack. EPMA analyzing found that some of the alteration product has a chemical composition between purealbite and the replaced detrital feldspar. For example, composition of replaced alkali feldspar is betweenmicrocline and albite, and content of altered plagioclase decreases continuously. This has been regardedas direct evidence for fluid replacement, for feldspar crystallized from solution or magma is usually withfixed chemical composition. Taking alkali feldspar as an example, although Kf and Ab forming completeisomorphous admixture in high temperature, they exsolved out as two relative pure phases while temperature decreases.

关键词： low temperature albitization sandstones fluid origin North Tarim.

Application of ERS-1 scatterometer data to studying land surfaces ──Distributive characteristic of backscattering coefficient over china land surfaces

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Chinese Science Bulletin 1998年第23期43卷 1950-1955页

作者： WANG Xiangyun 1, WANG Chao 2. GUO Huadong 2.and SHI Yangshen 1 1. Department of earth sciences, Nanjing {2., Nanjing 2.0093, china 2. Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, china Department of earth sciences Nanjing University Nanjing 210093 China Inst. of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

ERS 1 WSC data were obtained by international cooperation. The distributive characteristics of radar backscattering coefficient image of china land surface are analyzed and the research results are presented. The capability of ERS 1 WSC data for monitoring land surfaces is investigated. The results show that the radar backscattering coefficient images can reveal the natural landform features of china land. Using the WSC data can discriminate six types of major land coverage, including evergreen vegetation and snow covered region, vegetation and crops, mountains, grassland, desert and grassland, desert. On the whole, the radar backscattering coefficient image of china land is the synthesis of the vegetation map and terrain map. Statistical study of the typical terrain shows that the radar backscatter coefficients of china land range from -2. dB to -5 dB. The lowest value corresponds to the deserts of Badain Jaran, Takla Makan, and Tengger. The highest value corresponds to snow covered regions of Himalaya Mountains and Tianshan Mountains.

关键词： ERS 1 WSC radar backscattering coefficient land surfaces coverage.

Experimental study of ore gabbro liquid immiscibility

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Science china earth {2. 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4 1. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2. Wuhan {2., Wuhan 430072. china 3. Institute of Geology, china Seismological Bureau, Beijing 10002., china 4. Faculty of earth sciences, china university of geosciences, Wuhan 430074, china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.