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THE ALTUN—NORTH QAIDAM ECLOGITE BELT IN WESTERN china—ANOTHER HP-UHP METAMORPHIC BELT TRUNCATED BY LARGE SCALE STRIKE-SLIP FAULT IN china

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地学前缘 2000年第S1期7卷 254-255页

作者： Zhang Jianxin, Xu Zhiqin, Yang Jingsui, Li Haibing, wu Cailai(Institute of geology, chinese academy of Geological {4., 26 Baiwanzhuang, Beijing 100037,{4., E\|mail: zjx66@***)

The Altun and North Qaidam Mountains at the northern margin of Qinghai\|Tibet plateau are separated by the Altyn Tagh sinistral strike\|slip fault, which is one of the largest strike\|slip fault systems in the world and was considered as the key element in the escape tectonics model for Euraisa\|India continent\|continent ***,the eclogites within quratzifeldspathic gneisses or pelitic gneisses characterized by amphibolite\|facies paragenesis were discovered in the Altun and the North Qaidam Mountains(Fig.1). They occur as lens or boundins within the Altun Group and Dakendaban Group respectively which previously were considered as metamorphic basement of Tarim block and Qaidam block. Our studies indicate that the eclogites outcrop in both the Altun and North Qaidam Mountains show similar occurrences, associated country rocks, rock and mineral assemblages, p\|T\% estimates, geochemistryand protolith feature and ages of peak metamorphism (see table) . The garnet\|omphacite\|phengite geothermobarometer gave equilibrium condition of \%p\%=2 8～3 0GPa and t =820～850℃ for the Altun eclogite and p =2 8GPa and \%t\%=730℃ for North Qaidam eclogite respectively(Fig..2). These p\|T conditions are in the coesite stability field. Moreover, Po lycrystalline quartz pseudomorphs after coesite have been identified in the Dulan area, North Qaidam Mountains (Song et al, in review). Therefore, these features suggest that both eclogites of Altun and North Qaidam Mountains probably are a same HP\|UHP metamorphic belt formed from the same of Early Paleozoic age deep subduction and collision, and subsequently displaced by the Altyn Tagh *** case is similar to the Dabie\|Sulu HP\|UHP metamorphic zone which was truncated by the Tanlu sinistral strike\|slip fault and splitted it into two distincts, the Dabie region and Sulu region. These correlations support an about 350～4.0km displacement of the Altyn Tagh sinistral strike\|slip fault (Fig.1).

关键词： Altun mountains North Qaidam Mountains HP\|UHP metamorphic b elt Altyn Tagh fault

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Late Mesozoic Exhumation of the Huangling Massif:Constraints on the Evolution of the Middle Yangtze River

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 250-264页

作者： SU Jianchao LIN Xu LI Chang’an Jolivet MARC wu Lin CHENG Feng DENG Bin wu Zhonghai CHEN Xiaokang HU Chengwei School of Geography and Information Engineering China University of GeosciencesWuhan 430074China College of Civil Engineering and Architecture China Three Gorges UniversityYichangHubei 443002China Géosciences Rennes CNRS-UMR6118Univ RennesRennesFrance State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBejing 100029China Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing 100871China State Key Laboratory of Oil and Gas Reservoir geology and Exploitation/Chengdu University of Technology Chengdu 100871China Institute of Geological Mechanics Chinese Academy of Geological ScienceBeijing 100081China

Plate subduction leads to complex exhumation processes on *** Huangling Massif lies at the northern margin of the South china *** the Huangling Massif was exhumed as a watershed of the middle reaches of the Paleo-Yangtze River during the Mesozoic remains under *** examined the exhumation history of the Huangling Massif based on six granite bedrock samples,using apatite fission track(AFT)and apatite and zircon(U-Th)/He(AHe and ZHe)*** samples yielded ages of 157–132 Ma(ZHe),119–106 Ma(AFT),and 114.72 Ma(AHe),*** modeling revealed that three phases of rapid cooling occurred during the Late Jurassic–Early Cretaceous,late Early Cretaceous,and Late *** exhumation processes led to the high topographic relief responsible for the emergence of the Huangling *** integrated of our new data with published sedimentological records suggests that the Huangling Massif might have been the watershed of the middle reaches of the Paleo-Yangtze River since the *** that time,the rivers flowed westward into the Sichuan Basin and eastward into the Jianghan *** subduction of the Pacific Plate beneath the Asian continent in the Mesozoic deeply influenced the geomorphic evolution of the South china Block.

关键词： apatite zircon (U-Th)/He fission track Huangling Massif Yangtze River

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In situ U-Pb dating of titanite by LA-ICPMS

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Science Bulletin 2012年第20期 2507-2529页

作者： SUN JinFeng 1,2,YANG JinHui 1,wu FuYuan 1,XIE LieWen 1,YANG YueHeng 1,LIU ZhiChao 1,2 & LI XianHua 1 1 State Key Laboratory of Lithospheric Evolution,Institute of geology and geophysics,chinese {4. of {4.,Beijing 100029,china 2 Graduate University of the chinese academy of sciences,Beijing 10004.,china

Titanite is an ideal mineral for U-Pb isotopic dating because of its relatively high U,Th and Pb ***,we developed a technique for U-Pb dating of titanite using the 193 nm ArF laser-ablation system and Agilent 7500a *** of titanite (BLR-1 and OLT-1) and zircon (91500 and GJ-1) were dated using single spot and line raster scan analytical *** check the matrix effect,titanite (BLR-1) and zircon (91500) standards were analyzed as the external *** weighted mean 206 Pb/238 U ages of OLT-1 titanite are 1015±5 Ma (2,n=24. and 1017±6 Ma (2,n=24. by single spot and line raster scan analyses,respectively,using BLR-1 titanite as the external *** ages are consistent with its reference age of about 1014.***,using 91500 zircon as the external standard,the weighted mean 206 Pb/238 U ages are 917±4.Ma (2,n=24. and 927±5 Ma (2,n=24. for BLR-1 titanite,and 891±4.Ma (2,n=24. and 901±5 Ma (2,n=24. for OLT-1 titanite by single spot and line raster scan analyses,*** is evident that these ages are ～12% younger than their reference *** results reveal that significant matrix effect does exist between different kinds of minerals during LA-ICPMS U-Pb age determination,whereas it is insignificant between same ***,same mineral must be used as the external standard for fractionation corrections during in situ LA-ICPMS U-Pb age *** addition,we determined U-Pb ages for titanites from the Early Cretaceous Fangshan pluton,which indicates a rapid cooling history of this pluton.

关键词： In situ titanite U-Pb dating LA-ICPMS single spot line raster scan matrix effect

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Geochemical and Nd Isotopic Characteristics of Some Rocks from the Paleoarchaean Chentaigou Supracrustal, Anshan Area, NE china

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Continental Dynamics 1997年第1期 39-46页

作者： WAN Yusheng ZHANG Zongqing wu Jiashan SONG Biao LIU Dunyi (Institute of geology, chinese academy of Geological {4. (CAGS), Beijing 100037,{4.)

The Chentaigou supracrustal of Paleoarchaean age is located in the Chentaigou-Baijiafen area, Anshan City, Liaoning Province, and composed mainly of amphibolite, quartzite and biotite-plagioclase schist, with a small amount of meta-acid volcano-sedimentary rock. They have undergone several episodes of metamorphism. Zir- con ages of the trondhjemitic veins and the leptite （Song et al., 1994. suggest that the supracrustal rocks in the area were formed around 3.35 Ga ago. Our geochemical and Sin-Nd isotopic results indicate that the trondhjemitic veins intruding the Chentaigou supracrustal may be derived from the 3.8 Ga Baijiafen trondhjemite. On the other hand, although the calculated initial εNdvalue （-2.11） of the leptite, the meta-acid volcanosedimentary rock constituting one part of the supracrustal, is similar to that of the trondhjemitic veins, their element distributions, REE patterns in particular, are quite different. This suggests that the parent rock of the leptite was formed by the melting of some ancient continental material which is distinct from the 3.8 Ga Baijiafen trondhjemite. The amphibolite shows a geochemical composition similar to young island arc tholeiite. Eight samples of the amphibolite give a Sin-Nd isochron age of 2979 ± 384.（2σ） Ma, which is considerably younger than the zircon ages of the trondhjemitic veins and leptite. These dais are interpreted as recording a late metamorphic event. The rock association and geochemical compositions further indicate that the Chentaigou supracrustal was formed upon an old continental basement, probably in a tectonic environment similar to a modern island arc system.

关键词： Chentaigou supracrustal,. Paleoarchaean Geochemisny Chronology Anshan area

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Sedimentary processes and development of the Zenisu deep-sea channel, Philippine Sea

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chinese Science Bulletin 2003年第B6期48卷 92-97页

作者： wu Shiguo~(1,2) & Sakamoto Izumi~3 1. Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 2. Kiy Laboratory of Marine Sedimentology and Environmental geology, State Oceanic Administration. Qingdao 266061, china 3. Japan Marinc Science & Technology Center. Yokosuka 2370061. Japan Institute of Oceanology Chinese Academy of Sciences Qingdao China Key Laboratory of Marine Sedimentology and Environmental geology State Oceanic Administration Qingdao China Japan Marine Science & Technology Center Yokosuka Japan

Zenisu deep-sea channel originated from a volcanic arc region, Izu-Ogasawara Island Arc, and vanished in the Shikoku Basin of the Philippine Sea. According to the swath bathymetry, the deep-sea channel can be divided into three segments. They are Zenisu canyon, E-W fan channel and trough-axis channel. A lot of volcanic detritus were deposited in the Zenisu Trough via the deep-sea channel because it originated from volcanic arc settings. On the basis of the swath bathymetry, submersible and seismic reflection data, the deposits are characterized by turbidite and debrite deposits as those in the other major deep-sea channels. Erosion or few sediments were observed in the Zenisu canyon,whereas a lot of turbidites and debrites occurred in the E-W channel and trough axis channel. Cold seep communities,active fault and fluid flow were discovered along the lower slope of the Zenisu Ridge. Vertical sedimentary sequences in the Zenisu Trough consist of the four post-rift sequence units of the Shikoku Basin, among which Units A and B are two turbidite units. The development of Zenisu canyon is controlled by the N-S shear fault, the E-W fan channel is related to the E-W shear fault, and the trough-axis channel is related to the subsidence of central basin.

关键词：沉积过程菲律宾海海沟海洋沉积学四国盆地海洋深测术火山碎石地震数据浊流岩

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Terrestrial mollusc records from Xifeng and Luochuan L9 loess strata and their implications for paleoclimatic evolution in the chinese Loess Plateau during marine Oxygen Isotope Stages 24.22

Terrestrial mollusc records from Xifeng and Luochuan L9 loes...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： B.wu~(1,2) and N.Q.wu~1 1 Key Laboratory of Cenozoic geology and Environment,Institute of geology and {4.,chinese {4. of sciences,P.O.Box 9825,Beijing,100029,china 2 Graduate University of the chinese academy of sciences,Beijing,10004.,china

Marine Isotope Stages 24.22 is a key period of the Mid-Pleistocene Transition,however,its climate variability is still *** coarse-grained loess unit L9,one of the most prominent units in the chinese loess stratigraphy,yields a high potential terrestrial record of paleoclimatic and paleoenvironmental changes during this *** this study, two high-resolution terrestrial mollusc records of L9 loess strata from the Xifeng and Luochuan sequences in the chinese Loess Plateau were *** mollusc results show that the MIS 24.the early and late parts of MIS 22 were dominated by cold and dry *** mild-humid climate occurred in MIS 23 and the middle part of MIS *** climatic conditions at Xifeng region were cooler and more unstable compared to Luochuan region.A comparison of mollusc species composition and other proxies of L9 strata (MIS 24.22) with those of LI loess units(MIS 4.2) indicates that the L9 loess was not deposited under the most severe glacial conditions in Quaternary climate history as suggested in previous *** study shows that climatic conditions in the Loess Plateau during the L9 loess forming period were similar to that of gentle glacials(MIS 24.and MIS 22) and interglacial(MIS 23),as suggested by the marineδO *** cooling fluctuations occurred at 30 ka, 900 ka and 880 ka,which might hint to the global "900 ka cooling event".The "900-ka event" in the Loess Plateau does not seem to be a simple long glaciation,but rather several complex climatic fluctuations superposed on a general cooling *** uplift of the Tibetan Plateau and the general cooling experienced by the Earth during this period may have resulted in abundant dust sources and increased dust transport capability,as indicated by increased grain size and the mass accumulation rate of L9 loess.

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Carbon isotopic characteristics and their genetic relationships for individual lipids in plants and sediments from a marsh sedimentary environment

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Science china Earth sciences 2005年第8期48卷 1203-1210页

作者： DUAN Yi1, ZHANG Hui1, ZHENG Chaoyang1, wu Baoxiang1 & ZHENG Guodong2 1. Lanzhou Institute of geology, chinese academy of sciences, Lanzhou 730000, china 2. Department of Earth & Planetary System Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-85Japan Lanzhou Institute of geology Chinese Academy of Sciences Lanzhou China Department of Earth & Planetary System Science Graduate School of Science Hiroshima University Higashi-Hiroshima Japan

The carbon isotopes of individual lipids in herbaceous plants and tree leaves in Ruoergai marsh were measured by the GC-IRMS analytical technique in order to understand the inherent relationships of carbon isotopes between sedimentary and plant lipids from typical marsh environment. The analytical results show that the carbon isotopic compositions of n-alkanes in different kinds of plants differ significantly. Mean δ 13C values of n-alkanes in her-baceous plants (?32.2‰―?36.9‰) are 3.3‰ lower than those in woody plant (?27.2‰― ?35.0‰). The carbon isotopic compositions of fatty acids in organisms (?30.3‰― ?36.2‰) are very similar to those of n-alkanes and the δ 13C values for unsaturated fatty acids are within the range of those for saturated fatty acids. The differences in δ 13C values between plant lipids are obvious and range from 2.4. to 7.8‰. It is observed that the carbon isotopic compositions of sedimentary lipids are closely related to those of plant lipids. The carbon isotopic compositions (?27.0‰―?36.9‰) of n-alkanes, ≥C16 fatty acids, n-alkanols, sterols and n-alkanones in the sediments are similar to those of plant lipids and the carbon isotopic compositions of short-chain sedimentary lipids are similar to those of long-chain sedimentary homologues. These indicate that the sedimentary lipids are derived from high plants. However, the δ 13C values of C14.0 and C15:0 fatty acids in the sediments are lighter than those of the same carbon number saturated homologues in plants, reflecting the genetic features partially derived from bacteria. These data provide scientific evidence for carbon isotope-applied research of individual lipids.

关键词： marsh environment, plants, sediments, individual lipids, carbon isotopic compositions, genetic relationships.

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Combined chemical separation of Lu,Hf,Rb,Sr,Sm and Nd from a single rock digest and precise and accurate isotope determinations of Lu-Hf,Rb-Sr and Sm-Nd isotope systems using Multi-Collector ICP-MS and TIMS

Combined chemical separation of Lu,Hf,Rb,Sr,Sm and Nd from a...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Yue-heng Yang~(a,b,*),Hong-fu Zhang~a,Zhu-yin Chu~(a,b),Lie-wen Xie~a,Fu-yuan wu~a a State Key Laboratory of Lithospheric Evolution,Institute of geology and geophysics,chinese {4. of {4.,Beijing 100029,china b Laboratory for Radiogenic Isotope Geochemistry,Institute of geology and geophysics,chinese {4. of {4.,Beijing 100029,china

A combined procedure for separating Lu,Hf,Rb,Sr,Sm and Nd from a single sample digestion is presented in this *** procedure consists of the following four steps:(1) sample dissolution in a mixture of concentrated HF-HNO-HClO;(2) Lu and Hf separation from the Rb,Sr,LMREE and other matrix elements by HF-free extraction chromatography;(3) Rb,Sr and LMREE separation from other matrix elements using a cation-exchange resin;(4. Sm and Nd separation from others LMREE by extraction *** feasibility,flexibility and reproducibility of Rb-Sr,Sm-Nd and Lu-Hf isotope systems are demonstrated for international standard solutions and Certified Reference Materials(CRMs). Results show good agreement with previously reported values by isotope dilution methods,indicating the technique has fewer problems in respect to well-known sample inhomogeneity of natural geological materials and demonstrating its potential application to the study of limited and precious terrestrial rocks or minerals(like peridotite,kimberlite and xenoliths) and extra-terrestrial samples(like lunar rock and meteorites).

关键词： Chromatography Isotope dilution Lu-Hf Rb-Sr Sm-Nd Geological samples MC-ICP-MS TIMS

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In situ U-Pb dating of xenotime by laser ablation(LA)-ICP-MS

In situ U-Pb dating of xenotime by laser ablation(LA)-ICP-MS

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： LIU ZhiChao~(1,2),wu FuYuan~(1*),GUO ChunLi~3,ZHAO ZiFu~4.YANG JinHui~1 & SUN JinFeng~(1,2) 1 State Key Laboratory of Litho spheric Evolution,Institute of geology and geophysics,chinese {4. of {4.,Beijing 100029,china 2 Graduate University of chinese academy of sciences,Beijing 10004.,china 3 Institute of Mineral Deposits,chinese {4. of Geological {4.,Beijing 100037,china 4.School of Earth and Space {4.,University of Science and Technology of{14.,Hefei 230026,china

Xenotime is an ideal mineral for U-Th-Pb isotopic dating because of its relatively high U and Th contents,but typically low concentration of common *** characteristics,and the fact that it is widespread throughout various types of rocks,suggest that the U-Th-Pb dating of xenotime has broad *** of U-Pb dating on xenotime by ion microprobe(such as SHPJMP) have increased in recent years,whereas studies by laser ablation(LA)-ICP-MS are still *** this study,we developed a technique for U-Pb dating of xenotime using the 193 nm ArF laser-ablation system and Agilent 7500a *** evaluate the reliability of our method,a xenotime standard,BS-1,was analyzed and calibrated against another xenotime standard,*** weighted mean Pb/U ages of 510.1±5.2 Ma(2a,n = 21),509.8±4.3 Ma(2 a,n = 21) and 510.0±4.6 Ma(2a,n = 21) were obtained using beam diameters of 16,24.and 32μm,*** ages are identical to those determined by ID-TTMS method(weighted mean Pb/U age of 508.8±1.4.Ma),which supports the reliability of our LA-ICP-MS *** also analyzed xenotimes in leucogranites from South Tibet and granites from Xihuashan in southern china,and obtained accurate and precise ***,we observed systematic differences in Pb/U fractionation among xenotime,monazite and *** matrix-effect resulted in either under-correction or over-correction of fractionation,and thus led to inaccurate ***,a matrix -matched material is required for U-Pb dating of xenotime by LA-ICP-MS.

关键词： xenotime laser ablation(LA)-ICP-MS U-Pb dating

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THREE-DIMENSIONAL DEFORMATION ALONG THE ALTYN TAGH FAULT ZONE AND UPLIFT OF THE ALTYN MOUNTAIN, NORTHERN TIBET

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地学前缘 2000年第S1期7卷 257-258页

作者： Li Haibing, Yang Jingsui, Xu Zhiqin, Zhang Jianxin, wu Cailai,Shi Rendeng (Institute of geology, chinese academy of Geological {4., 26 Baiwanzhuang Road, Beijing 100037,{4.,E\|mail: lihaibing@*** yangjsui@***)

he convergence between India and Eurasia is partly accommodated by motion of a few large blocks along strike\|slip faults. About 1800km long Altyn Tagh fault strikes in N60～80°E and allows the northeastward displacement of the Tibet plateau relative to the Tarim. The Altyn Tagh fault zone is a typical transpressional fault zone, characterized by blocks rotation and crustal shortening and vertical extrusion of blocks within the Altyn Tagh strike\|slip system. Differences of three\|dimensional deformation and configuration of the active structures are recognized at different segment of the Altyn Tagh fault zone.1\ Structural configuration of the Altyn Tagh fault zone\;In the Altyn Tagh strike\|slip fault zone, the assemblage pattern of the (active) faults is in the form of parallel plumes, especially in the eastern and the western segments of the Altyn Tagh fault zone. These plumes structures in the eastern segment are assembled by string\|like left lateral strike\|slip fault and broom\|like thrusting faults, and in the western segment by arc\|like left lateral strike\|slip faults along with thrusting faults and normal faults. In the middle segment of the Altyn Tagh fault zone, the structures are characterized by the string\|like left lateral strike\|slip faults in the center and reverse thrusting faults on the two sides.

关键词： three\|dimensional deformation uplift mountain building t ranspression Altyn Tagh fault Tibet

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