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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 {2., Beijing 100081, china 2. institute of geology, chinese Academy of Geological {2., Beijing 10003., china 3. institute of geology and Geophysics, chinese Academy of {2., 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.

The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

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Science china(Life sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2.3. KONG Fanjing1,2.3.& ZHENG Mianping1,2.3.1. R&D Center for Saline Lake and Epithermal Deposits, {3. Academy of Geological sciences, Beijing 10003.,{2. 2. key Open laboratory of Saline Lake resources and Environment, {3. Academy of Geological sciences, Beijing 10003.,{2. 3. {13. of mineral resources, {3. Academy of Geological sciences, Beijing 10003.,{2. R&D Center for Saline Lake Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China key Open laboratory of Saline Lake {2. Environment Chinese Academy of Geological Sciences Beijing 100037 China institute of mineral {2. Chinese Academy of Geological Sciences Beijing 100037 China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (2. h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

Criteria for defining and recognizing the various orders of sequences in outcrop sequence stratigraphy

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Science china Earth sciences 2004年第7期47卷 618-629页

作者： WANG Xunlian Faculty of Earth sciences and mineral {2.,{3. University of Geosciences, Beijing 100083.{3. State key laboratory of Palaeobiology and Stratigraphy, Nanjing institute of geology and Palaeontology, chinese Academy of sciences, Nanjing 2.0008,{3. 1. Faculty of Earth sciences and mineral {2. China University of Geosciences 100083 Beijing China 2. State key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

The regional distribution in different depositional facies belts is here regarded as an important criterion for defining and recognizing the various orders of sequences. The third-order sequence is possibly global in nature, which may be discerned in different depositional facies belts in one continental margin and can be correlated over long distances, sometimes even worldwide. Commonly, correlation of subsequence (fourth-order sequence with time interval of 0.51.5 Ma) is difficult in different facies belts, although some of them may also be worldwide in distribution. A subsequence should be able to discern and correlate within at least one facies belt. The higher-order sequences, including microsequence (fifth-order sequence) and minisequence (sixth-order sequence), are regional or local in distribution. They may reflect the longer and shorter Milankovitch cycles respectively. Sequence and subsequence are usually recognizable in different facies belts, while microsequence and minisequence may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits. A brief discussion is made on the essential conditions for correct identification of sequences, useful methods of study, and problems meriting special attention in outcrop sequence stratigraphy.

关键词： outcrop sequence stratigraphy, facies belt, sequence, subsequence, microsequence, minisequence, meter-scale cyclothem, Milankovitch cycle.

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 {2. of Geochemistry, chinese Academy of sciences, Guangzhou 510640, china 2. Graduate University of chinese Academy of sciences, Beijing 10003., china 3. SHRIMP isotope laboratory, chinese Academy of Geological sciences, Beijing 10003., china 4. {2. 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-13.) 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.

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 , {2. Academy of {3. , Beijing 100101, china 2. institute of geology , {2. Academy of {3. , Beijing 10002., china 3. institute of High Energy Physics , {2. Academy of {3. , 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.

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2. WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3.1. State key laboratory of Marine {2., Tongji University, Shanghai 2.0092. china 2. institute of {2. and Geophysics, chinese Academy of sciences, Beijing 10002., china 3. institute of Botany, chinese Academy of sciences, Beijing 100093. china State key laboratory of Marine {2. Tongji University Shanghai{3. institute of geology and Geophysics {2. Academy of {3. Beijing china institute of Botany chinese Academy of {2. Beijing{3.

The deep sea records from the ODP Sites 1143.and 1144 in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13., Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 2. ka cycles. Although G. ruber δ 13. of Site 1143.is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2. TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing institute of geology and Palaeontology, {2. Academy of sciences, Nanjing 2.0008, china 2. Henan institute of Geological Survey, Zhengzhou 450007, china 3. State key laboratory of Geological Processes and mineral {13. at china University of Geosciences, Wuhan 43.074, china 4. Faculty of Material sciences and Chemical Engineering, china University of Geosciences, Wuhan 43.074, china 1. Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan institute of Geological Survey Zhengzhou 450007 China 3. State key laboratory of Geological Processes and {2. {3. at china University of Geosciences Wuhan 430074 China 4. Faculty of Material sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3.into carbonate

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Science china Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2. LI HuaLing1,3. LIU WeiGuo4, WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese Academy of {2., Xining 810008, china 2.State key laboratory of Environmental Geochemistry, institute of Geochemistry, chinese Academy of {2., Guiyang 550002. china 3.Nanjing institute of geology and {{12. resources, Nanjing 2.0016, china 4 State key laboratory of Loess and Quaternary geology, institute of Earth Environment, chinese Academy of {2., Xi’an 710075, china 5 State key laboratory for {{12. Deposits Research, Department of Earth {2., Nanjing University, Nanjing 2.0093. china 1. Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China 2. State key laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China 3. Nanjing institute of geology and {2. {3. 210016 Nanjing China 4. State key laboratory of Loess and Quaternary {2. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. State key laboratory for {2. Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.3. was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3. between carbonate and B(OH)3.in seawater range 0.93. and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3.values between carbonate and B(OH)3.in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3.with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3. between B(OH)4- and B(OH)3.is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

Oxygen isotope compositions of eclogites in Rongcheng,Eastern china

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chinese Science Bulletin 2003年第4期48卷 372-378页

作者： CHU Xuelei1,2. GUO Jinghui1,2. FAN Hongrui1,2.& JIN Chengwei1 1. {3. of geology and Geophysics, {2. Academy of sciences, Beijing 10002., china 2. key laboratory for mineral {13. Research, {2. Academy of sciences, Beijing 100101, china Correspondence should be addressed to Chu Xuelei institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China key laboratory for {2. {3. Research Chinese Academy of Sciences Beijing 100101 China

Collected from the Rongcheng region, Shan-dong Province, the three types of eclogites suffering the UHP (i.e. ultra-high pressure) metamorphism have obviously dif-ferent oxygen isotope compositions. The eclogites occurring in regional orthogneisses and ultramafic rocks have the oxy-gen isotope compositions of normal eclogites in the world,but the eclogites existing in marbles are extremely enrichedin 18O. By applying oxygen isotope geothermometry, for theall types of eclogites, the temperature estimates of quartz-garnet pair, in principle, indicate the formation temperatures of eclogites, so that the peak-metamorphic temperatures are estimated to be averagely little higher than 800℃, which are consistent with the estimates by using other geothermome-ters according to cation partitioning between coexistingphases. The d 18O values of eclogitic inclusions hosted inmarbles from Yangguantun, Rongcheng region, are farhigher than the values of eclogites (including eclogitic inclu-sions in marbles) from the Dabieshan and other places of the Sulu. The oxygen isotope compositions of various mineralsindicate that the formation temperatures of eclogites fromthe Rongcheng region, in general, are higher than that from the Dabieshan and the southwestern part of the Sulu, but the dispersive temperatures estimated by different mineral pairs probably reflect that the UHP eclogites from the Rongcheng region generally suffered overprinted metamorphisms dur-ing the exhumation.

关键词：苏鲁超高压变质带 UHP 山东荣成榴辉岩氧同位素成分

Hyperconcentrated flows as influenced by coupled wind-water processes

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Science china Earth sciences 2005年第11期48卷 1990-2000页

作者： XU Jiongxin institute of Geographical sciences and Natural {2. Research, {3. Academy of sciences key laboratory of Water Cycle and Related Land Surface Processes, {3. Academy of sciences, Beijing 100101, china 1. key laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Using data from more than 40 rivers in the middle Yellow River basin, a study has been made of the influence of coupled wind-water processes on hyperconcentrated flows. A simple “vehicle” model has been proposed to describe hyperconcentrated flows. The liquid phase of two-phase flows is a “vehicle”, in which coarse sediment particles are carried as solid-phase. The formation and characteristics of hyperconcentrated flows are closely related with the forma-tion and characteristics of this liquid-phase and solid-phase. Surface materials and geomorphic agents of the middle Yellow River basin form some patterns of combination, which have deep influence on the formation and characteristics of liquid- and solid-phases of hyperconcentrated flows. The combination of high percentages of relatively coarse material with low percentages of fine material appears in the area predominated by the wind process, where the supply of rela-tively coarse sediment is sufficient, but the supply of relatively coarse sediment is not. The com-bination of low percentages of relatively coarse material with high percentages of fine material appears in the area predominated by the water process, where the supply of fine sediment is sufficient, but the supply of fine sediment is not. In the area predominated by coupled wind-water processes appears the combination of medium percentages of coarse and fine materials, and thus both coarse and fine sediments are in relatively sufficient supply. The manner in which the mean annual sediment concentrations of liquid- and solid-phases vary with total suspended sediment concentration is different. With the increased total suspended sediment concentration, mean annual sediment concentration of liquid-phase increased to a limit and then remained constant; however, mean annual sediment concentrations of solid-phase in-creased continuously. Thus, the magnitude of total suspended sediment concentration depends on the supply conditions of relatively coarse sedime

关键词： river sediment, hyperconcentrated flows, liquid-solid two-phase flows, wind process, fluvial process, Yellow River