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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 2. Graduate University of Chinese Academy of Sciences, {2. 100039, china 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, {2. 100037, china 4. institute of geology and Geophysics, Chinese Academy of Sciences, beijing 10002., china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese Academy of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth Sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2.& CAI YongEn2.1 institute of Crustal Dynamics, china Earthquake Administration, {2. 100085, china 2.Department of Geophysics, Peking University, {2. 100871, china institute of Crustal Dynamics China Earthquake Administration Beijing China Department of Geophysics Peking University Beijing China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GPS observation station is most densely deployed in the world. The unprecedented GPS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GPS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2.102. Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 2..7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GPS temporal series data Chi-Chi earthquake

SEISMICITY TENDENCY PREDICTION BEFORE 2.2. IN china MAINLAND FROM ASTRONOMIC PERIODICITIES

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地震地质 1990年第1期 6-11页

作者： Du Pin-ren (institute of geology,State {2. bureau)

The correlations between large earthquakes in china continent and periodicities of the Moon’s movement and the solar activity are statistically analysed and the following points are revealed:1. The earthquakes with ≥7.5 in Qing-Zang fault-block region have 18.6-yr periodicity of the Moon’s nodes motion.2. The earthquakes with M≥7.1 in Xinjiang fault-block region have 8.85-yr periodicity of the Moon’s perigee motion.3. The earthquakes with M≥7.0 in china mainland have the tendency to cluster around times of minima of sunspot cycles and in the even solar cycles.4. The earthquakes with M≥8.0 in china continent have the tendency to cluster around the valley times of the secular cycles of the solar *** to above correlations, the prediction of seismicity tendency can be given as follows: In china continent, especially Western china, the current active seismic period should continue up to the end of this century. The next active period would be 2.06-2.15.

关键词： Ascending node Perigee Solar activity Seismicity

Surface deformation at the epicenter of the May 12.2.08 Wenchuan M8 Earthquake,at Yingxiu Town of Sichuan Province,china

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Science china(Technological Sciences) 2008年第S2期51卷 154-163页

作者： DONG ShaoPeng,HAN ZhuJun & AN YanFen National Center of Seismic Fault Study,institute of geology,{2. Earthquake Administration,beijing 10002.,{2. National Center of Seismic Fault Study Institute of Geology China Earthquake Administration Beijing China

Surface deformation,along National Highway 2.3 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,china,is surveyed and measured in *** results show two distinct *** is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72.m,and the short-ening amount is 0.38 m,which reflects thrust shortening deformation is not *** crust uplift amount of 2.71 m is distributed in a belt with width of 60 *** model of lower crustal flow proposed by Royden et al.(1997) about the dynamic process in eastern margin of the Tibetan Plateau seems more suitable to explain the seismic surface deformation characteristics at Yingxiu Town,the epicenter of the May 12.2.08 Wenchuan M8 Earthquake.

关键词： Wenchuan M8 Earthquake Yingxiu Town surface deformation

Digital image analysis of palaeoenvironmental records and applications

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Chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South china Sea institute of Oceanology, Chinese Academy of Sciences. Guangzhou 510301, china 2. State Key Laboratory of Loess and Quaternary geology, Earth Environmental institute, Chinese Academy of Sciences, Xi’an 710075, china 3. institute of geology and Geophysics, Chinese Academy of Sciences, beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Integrative inversion of land surface component temperature

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Science china Earth Sciences 2005年第11期48卷 2011-2019页

作者： FAN Wenjie1 & XU Xiru1,2.1. institute of Remote Sensing and Geographical Information System, Peking University, beijing 100871,{2. 2. Center of Remote Sensing and GIS of beijing Normal University, beijing 100875,{2. institute of Remote Sensing and Geographical Information System Peking University Beijing China Center of Remote Sensing and GIS of beijing Normal University Beijing China

In this paper, the row winter wheat was selected as the example to study the com-ponent temperature inversion method of land surface target in detail. The result showed that the structural pattern of row crop can affect the inversion precision of component temperature evi-dently. Choosing appropriate structural pattern of row crop can improve the inversion precision significantly. The iterative method combining inverse matrix was a stable method that was fit for inversing component temperature of land surface target. The result of simulation and field ex-periment showed that the integrative method could remarkably improve the inversion accuracy of the lighted soil surface temperature and the top layer canopy temperature, and enhance inver-sion stability of components temperature. Just two parameters were sufficient for accurate at-mospheric correction of multi-angle and multi-spectral thermal infrared data: atmospheric trans-mittance and the atmospheric upwelling radiance. If the atmospheric parameters and component temperature can be inversed synchronously, the really and truly accurate atmospheric correction can be achieved. The validation using ATSRII data showed that the method was useful.

关键词： components temperature, inverse pattern, atmospheric correction

Target selection and transfer trajectories design for exploring asteroid mission

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Science china(Technological Sciences) 2010年第4期53卷 1150-1158页

作者： CUI PingYuan1,QIAO Dong1,CUI HuTao2.& LUAN EnJie3 1 School of Aerospace Engineering,beijing institute of Technology,beijing 100081,china 2.Harbin institute of Technology,Harbin 150001,china 3 National Defense Science and Industry bureau,beijing 100048,china School of Aerospace Engineering Beijing Institute of Technology Beijing China Harbin institute of Technology Harbin China National Defense Science and Industry bureau Beijing China

Technique of target selection and profiles of transfer trajectory for Chinese asteroid exploring mission are studied systemically.A complete set of approaches to selecting mission targets and designing the transfer trajectory is ***,when selecting a target for mission,some factors regarded as the scientific motivations are ***,when analyzing the accessibility of targets,instead of the classical strategy,the multiple gravity-assist strategy is *** suitable and possible targets,taking into account scientific value and technically feasible,are obtained via selection and *** designing the transfer trajectory for exploring asteroid mission,an approach to selecting gravity-assist celestial body is ***,according to the mission constraints,the trajectory profile with 2.years △V-EGA for exploring asteroid is *** analyzing the trajectory profile,unexpected result that the trajectory would pass by two main-belts asteroids is ***,the original proposal is extended to the multiple flybys *** adds the scientific return for asteroid mission.

关键词： exploring asteroid target selection multiple flybys transfer trajectory

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , Chinese Academy of Sciences , beijing 100101, china {2. , Chinese Academy of Sciences , beijing 10002., china 3. institute of High Energy Physics , Chinese Academy of Sciences , beijing 100817 , china 4. beijing University of Science and Engineering , beijing 100083, china Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Characteristics and origin of mafic and ultramafic xenoliths in trachyandesite lavas from Heikongshan volcano,Tengchong,Yunnan Province,china

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Science china Earth Sciences 2010年第9期53卷 1295-1306页

作者： YU HongMei, LIN ChuanYong, SHI LanBin, XU JianDong & CHEN XiaoDe institute of geology,{2. Earthquake Administration, beijing 10002.,{2. institute of geology China Earthquake Administration Beijing China

The trachyandesite lavas from Heikongshan volcano of the Tengchong volcanic cluster, Yunnan Province contain relatively abundant mafic and ultramafic small xenoliths comprising mainly gabbro, pyroxenite and rare lherzolites, all less than 2.5 cm in size. Gabbro xenoliths are characterized by "open" texture represented by relatively abundant vesicles and ground-mass fillings, while pyroxenite xenoliths are characterized by equigranular and poikilitic texture. Their mineral compositions (clinopyroxene ± orthopyroxene ± plagioclase) are similar to those of phenocrysts in lavas, and their equilibration temperature (1000-112.°C) is consistent with the crystallization temperature of the phenocrysts (998-1108°C). Thus, the textures and compositions of these xenoliths are different from those of lower crustal and mantle xenoliths, and were derived from the magma chamber. Among them, the gabbroic xenoliths come from the crystal-bubble-liquid zone at the top of the magma reservoir, while the pyroxenite xenoliths come from the cumulates in the bottom of magma reservoir. The studied single lherzolite xenolith with porphyroclastic texture has similar mineral compositions to the mantle xenoliths from eastern china, and is considered to be of upper mantle origin. It was brought into magma reservoir by replenishment magma, and might have experienced a cooling event before eruption. The formation of xenoliths in trachyandesite flows largely reflects the ascent, storage, evolution and eruption processes of magma.

关键词： magma chamber xenoliths geothermo-barometry trachyandesite Heikongshan volcano Tengchong