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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 51064., china 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, china 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, Beijing 100037, china 4. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, 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 (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4.± 3.0 Ma and 230.4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 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 (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±4. 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.

Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science china(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, china 2. Research Center for Remote Sensing and GIS, Department of Geography, Beijing Normal University, Beijing 100875, china 3. Graduate University of Chinese Academy of Sciences, Beijing 100039, china 4. Department of Atmospheric Physics, Peking University, Beijing 100871, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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Science china Earth Sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2, YU Haifeng3, YE Haimin2, ZHAO Yu2 & ZHANG Dongsheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., china 2. Nanjing Institute of Geology and Mineral Resources, Nanjing 210016, china 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, china 4. The 2nd Regional Geological Investigation Party, Xinjiang Bureau of Geology and Mineral Resources, Changji 831100, china 1. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 2. Nanjing Institute of Geology and Mineral Resources Nanjing 210016 China 3. Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China 4. The 2nd Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 831100 China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4.and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2DM model ages of 4.0 to 580 Ma and positive εNd(331 Ma) values of 6.23 to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3 & WANG YingYing4.1 Institute of Geophysics and Geomatics,china University of Geosciences,wuhan 43.074,china 2 Department of Geography,Hong Kong Baptist University,Hong Kong 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,wuhan University,wuhan 43.074,china 4.Hubei Provincial Bureau of Meteorology,wuhan 43.074,china 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

Combined adjustment project of national astronomical geodetic networks and 2000' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2, SONG Lijie3, WEI Ziqing1, WANG Zhouping2, OUYANG Guichong2, XU Bilin2, WU Xiaoping3 and WANG Junqin4.1. Xi'an Research Institute of Surveying and Mapping, Xi'an 710054. china 2. Xi'an Informational and Technical Center of Surveying and Mapping, Xi'an 710054. china 3. Zhengzhou Institute of Surveying and Mapping, Zhengzhou 4.0052, china 4. The First Surveying Team of Tianjin, Tianjin 30014., china) Xian Research Institute of Surveying and Mapping Xi''an 710054 China Xi''an Informational and Technical Center of Surveying and Mapping Xi''an 710054 China Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2000' national GPS control network involve 4.519 terrestrial observational stations and 2666 GPS observational stations. In the terrestrial network, 25107 stations are height fixed and 234.2 stations are in three dimensions. 4.0793 terrestrial observations and 183668 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2 m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12 m, for the geodetic height is about 0.14.m, and for the three-dimensional position is averagely 0.3 m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3, ZHOU Su3, LI Jinfa4. XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, china 2. Development and Research Center, china Geological Survey, Beijing 100037, china 3. china University of Geosciences, Beijing 100083, china 4. china University of Geosciences, wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, Beijing 100812, china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of Geosciences 100083 Beijing China 4. china University of Geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

梦想无线电电子工作室(8)——工具·扳手篇(上)

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无线电 2024年第9期 9-13页

作者：杨法(BD4.AF) 不详

本期分享的手动工具是手动扳手(见图1)。五金手动工具中的扳手用于紧固和拆卸螺纹件,如螺母和螺栓的主力工具,也是无线电和电子爱好者拆装电子产品经常会用到的专业工具。虽然扳手在电子工作室的出镜率远不如螺丝刀,但仍是重要的工具。... 详细信息

本期分享的手动工具是手动扳手(见图1)。五金手动工具中的扳手用于紧固和拆卸螺纹件,如螺母和螺栓的主力工具,也是无线电和电子爱好者拆装电子产品经常会用到的专业工具。虽然扳手在电子工作室的出镜率远不如螺丝刀,但仍是重要的工具。平时我们随手使用得看似平平无奇的扳手,从种类、规格、材质、工艺方面都蕴含着诸多专业知识。

关键词：手动工具电子产品工作室扳手电子爱好者螺丝刀出镜率专业知识

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3, HUANG Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, china 2. School of Information Science and Engineering, Shandong University, Jinan 250100, china 3. Department of Chemical Engineering, Light Industry College of Shandong, Jinan 250100, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of Science and Technology, wuhan 43.074, china 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information Science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4. SUN Yangui5, WEI Xiangdong3 & XING Zuoyun6 1. Division of Granite Geology, china Geological Survey, Yichang 4.3003, china 2. Information Center of Ministry of Land and Resources, Beijing 100812, china 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 4.0053, china 4. Geological Institute, china Seismological Bureau, Beijing 100029, china 5. Geological Survey Institute of Qinghai Province, Xining 810032, china 6. china University of Geosciences, wuhan 43.074, china Division of Granite Geology China Geological Survey Yichang 443003 China Information Center of Ministry of Land and Resources Beijing 100812 China Geological Survey of Henan Province and Institute of Geological Research of Henan Province Zhengzhou 450053 China Geological Institute China Seismological Bureau Beijing 100029 China Geological Survey Institute of Qinghai Province Xining 810032 China china University of Geosciences Wuhan 430074 China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.