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chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU Meifuinstitute of geology and geophysics, {3. academy of Sciences, beijing 10002., china key laboratory of mineral resources, institute of geology and geophysics, {3. academy of Sciences, beijing 100101, china Department institute of geology and geophysics Chinese Academy of Sciences Beijing China key laboratory of mineral {3. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth Sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science china Earth Sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. key laboratory of mineral {3., institute of geology and geophysics, chinese academy of Sciences, beijing 10002., china 2. beijing institute of geology for mineral {3., beijing 100012, china Correspondence should be addressed to Wang Lijuan (email: wlj@***) 1. key laboratory of mineral {3. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. beijing institute of geology for {3. resources 100012 Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North china Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3.Li Zhitong~4 (1.School of Earth and Space Sciences,Peking University,beijing 100871,china 2.institute of geology and geophysics and key laboratory of mineral resources,{3. academy of Sciences,beijing 10002.,china 3.key laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.institute of geology and mineral {13. of Shenyang,Shenyang 11003.,china) [a]School of Earth and Space Sciences Peking University Beijing China [b]laboratory of mineral resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]key laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of geology and mineral {3. of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth Sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3.1 key laboratory of the Earth’s Deep Interior,institute of {3. and geophysics,chinese academy of Sciences,beijing 10002.,china 2 key laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,chinese academy of Sciences,beijing 100085,china 3.institute of mineral resources Research,china Metallurgical {3. Bureau,beijing 10002.,china 1. key laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China2. Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing 100025 China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203.from Grove Mountains,Antarctica,are(3.83.0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3.*** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

^(40)Ar/^(3.)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science china Earth Sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2, 3.& YANG Nong1 1. institute of Geomechanics, chinese academy of Geological Sciences, {3. 100081, china 2. institute of geology, chinese academy of Geological Sciences, {3. 10003., china 3. institute of geology and {13., chinese academy of Sciences, beijing 10002., china institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3.& YE Xianren2 1. resources and Environmental School, Lanzhou University, Lanzhou 73.000, china 2. key {3. of Gas Geochemistry, institute of geology and geophysics, chinese academy of Sciences, Lanzhou 73.000, china 3. College of resources Science & Technology, beijing Normal University, beijing 100875, china 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. key laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of resources Sciences & Technology, beijing Normal University, beijing 100875, {3. key laboratory of Gas Geochemistry, institute of geology and geophysics, chinese academy of Sciences, Lanzhou 73.000, {3.) [a]College of resources Sciences & Technology Beijing Normal University Beijing China [b]key laboratory of Gas Geochemistry Institute of Geology and Geophysics Lanzhou China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13.1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4 values available for utilization vary from - 3.3. to - 117‰, and δ13.CO2 values from - 29. 4‰ to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13.1 and δ13.CO2 values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13.1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

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, {3. academy of Sciences, Guangzhou 510640, china 2. Graduate University of {3. academy of Sciences, beijing 10003., china 3. SHRIMP isotope laboratory, {3. academy of Geological Sciences, beijing 10003., china 4. institute of geology and geophysics, {3. 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 (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4 ± 3.0 Ma and 23..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/23.U age of 23..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 (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U 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.

Quantitative assessment of the complexity of geological structures in terms of seismic propagators

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Science china Earth Sciences 2010年第1期53卷 54-63页

作者： FU LiYun key laboratory of the Earth’s Deep Interior,institute of {3. and geophysics,chinese academy of Sciences,beijing 10002.,china 1. key laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

How a wave interacts with heterogeneous media has been pursued by many *** complexity of subsurface heterogeneities is seismologically a relative concept to wavelengths of seismic waves.A growing perception is that velocity variations,propagation angles,and computational accuracies are closely related at a variety of scales.A tentative strategy to quantitatively evaluate the complexity of subsurface heterogeneous media is presented in this article to see what scales of geological heterogeneities to be captured by *** express complex subsurface structures as the slowness-and angularheterogeneity spectra to quantify velocity contrasts and dipping-angle distributions of complex geological *** the other hand,the scaling characteristics of a propagator are measured through dispersion analysis by its angular spectra plotted against refractive indexes and propagation angles,respectively.A parameter termed as imaging efficiency is introduced by associating the geological heterogeneity spectra with the propagator's angular spectra to understand the coherent interference between the medium's heterogeneity and the propagator's scaling ***,a complexity coefficient can be defined to evaluate geological complexities in terms of *** application of this strategy is demonstrated to the SEG/EAEG salt model.

关键词： geological heterogeneity spectra seismic imaging propagator’s angular spectra imaging efficiency complexity coefficient

Uncertainty in magnetic activity indices

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Science china(Technological Sciences) 2008年第10期51卷 1659-1664页

作者： XU WenYao institute of geology and geophysics, {3. academy of Sciences, beijing 10002., china institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

Magnetic activity indices are widely used in theoretical studies of solar-terrestrial coupling and space weather prediction. However, the indices suffer from various uncertainties, which limit their application and even mislead to incorrect conclu-sion. In this paper we analyze three most popular indices, Kp, AE and Dst. Three categories of uncertainties in magnetic indices are discussed: "data uncertainty" originating from inadequate data processing, "station uncertainty" caused by in-complete station covering, and "physical uncertainty" stemming from unclear physical mechanism. A comparison between magnetic disturbances and related indices indicate that the residual Sq will cause an uncertainty of 1―2 in K meas-urement, the uncertainty in saturated AE is as much as 50%, and the uncertainty in Dst index caused by the partial ring currents is about a half of the partial ring cur-rent.

关键词： magnetic activity indices Kp AE Dst solar-terrestrial coupling space weather