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Thrust Propagation in the Aqqikkol Lake Area, the East Kunlun Mountains, Northwestern china

Acta Geologica Sinica(English Edition) 2003年第4期77卷 468-478页

作者： CUI Junwen, CHEN Wen, LI Pengwu, ZHANG Xiaowei and LI Li institute of geology,{2., beijing 100037 institute of geology Chinese Academy of Geological Sciences Beijing 100037

The western segment of the East Kunlun Mountains is one of the poorly studied regions in northwestern china. Through a structural analysis of the typical sections, we have the following views: (1) There is a very well developed fault system in the western segment of the East Kunlun Mountains and thrust propagation, normal slip and decoupling are the chief deformation events in this area. (2. Although the thrusting started in the Late Carboniferous and Late Triassic-Early Jurassic, strong activity took place in the Miocene-Quaternary when the Kumkol basin was strongly downwarped. (3) The tectonic pattern of coexistence of N-directed thrust propagation and S-directed normal slip in this area is consistent with the general tectonic pattern of the northern Qinghai-Tibet plateau and also very similar to that of the Himalayan region on the southern margin of the Qinghai-Tibet plateau, but their directions between the thrust propagation are opposite and all the strong thrust propagations occurred from the Miocene-Pliocene to Quaternary, a period featuring strong collision between the Indian plate and the Eurasian plate and abrupt uplift of the Qinghai-Tibet plateau. This oppositely directed thrust propagation and normal slip reveal such kinematic characteristics as symmetric propagations of deep-seated materials towards the north and south beneath the Qinghai-Tibet plateau and gravitational sliding of superficial materials towards the interior of the plateau. Therefore, the establishment of the fault system in the study area may provide an approach to the study of deep processes of the northern Qinghai-Tibet plateau and the construction of a unified geodynamic model for the uplift of the Qinghai-Tibet plateau.

关键词： western segment of the East Kunlun Mountains thrust propagation normal slip plate collision dynamic model

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A Possible Long-tailed Bird with a Pygostyle from the Late Mesozoic Yixian Formation, Western Liaoning, china

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Acta Geologica Sinica(English Edition) 2005年第1期79卷 7-10页

作者： L Junchang1 and HOU Lianhai2.1 institute of geology,{2., beijing 100037 2.institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044 Department of Biology, Capital Normal University, beijing 100037 chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China Capital Normal Univ Dept Biol Beijing 100037 Peoples R China

An incomplete caudal vertebral series (IVPP V11309) from the Yixian Formation of late Mesozoic, Jianshangou area of Beipiao, western Liaoning Province, may represent a new bird. The tail is composed of at least 12.free caudal vertebrae and the most distal 5 caudal vertebrae co-ossified into a pygostyle. The pygostyle is plate-like and slightly curved dorsally. The anterior free caudals are amphiplatyan. The anterior caudal surfaces of the last three free caudals are concave, but their posterior articular surfaces are convex. The pygostyle is regarded as the first appeared flight apparatus during the evolutionary process from Archaeopteryx to neornithes. The pygostyle appeared in most early fossil birds and almost all the modern birds. Although their morphologies are different, they are basically formed by at least four last caudal vertebrae. The specimen V11309 is regarded as a bird rather than a non-avian theropod dinosaur based on the following characters: short caudal vertebrae, numerous pits present on the surfaces of the centra and, a foramen present between the basal part of the fused neural spines, which is similar to that of Struthio camelus. The discoveries of pygostyles from the therizinosauroids and oviraptorosaurs may provide strong evidence for supporting the origin of birds from small theropod dinosaurs. The structure of the pygostyle in specimen V11309 is different from those of Beipiaosaurus (Therizinosauroid) and Nomingia (oviraptorosaur). The most parsimonious interpretation is that these pygostyle-like structures are independently acquired by Beipiaosaurus and Nomingia during their evolutionary process.

关键词： western Liaoning Yixian Formation late Mesozoic pygostyle

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^(40)Ar-^(39)Ar dating and geological implication of auriferous altered rocks from the middle-deep section of Q875 gold-quartz vein in Xiaoqinling area, Henan,china

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chinese Science Bulletin 2002年第20期47卷 1750-1755页

作者： WANG Yitian, MAO Jingwen, LU Xinxiang & YE Anwanginstitute of Mineral Resources, chinese academy of geological sciences,{2., china institute of geological sciences, Henan Province, Zhengzhou 450053, china Lingbao Bureau of geology and Mineral institute of Mineral Resources Chinese Acad. of Geological Sciences Beijing 100037 China institute of geological {2. Henan Province Zhengzhou 450053 China Lingbao Bur. of Geol./Mineral Rsrc. Henan Province Lingbao 472500 China

The 40Ar-39Ar age method is employed in this work to analyze the auriferous altered rocks from the middle-deep section of the Q875 gold-quartz vein in the Xiao-qinling area, and the results show that the main gold deposition of the Q875 occurred in ca. 12.-12. Ma. As a typical gold-bearing quartz vein in this gold-rich area, the age data obtained from the Q875 also constrain on the metallogenic time of the lode gold deposits developed in the same geological settings. This geochronological study supplies new evidence for further understanding the timing of gold mineralization, the genesis of gold deposits and the geodynamic settings in Xiaoqinling area.

关键词： 40Ar-39Ar dating auriferous altered rock Q875 gold-quartz vein lode gold deposit metallogenic time Xiaoqinling.

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science china Earth sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2. DU Andao2. GAO Yongfeng3 & HUANG Wei4 1. institute of Mineral Resources, chinese academy of geological sciences,{2., china 2. National Center of Geoanalysis, chinese academy of geological sciences,{2., china 3. Shijiazhuang College of Economy, Shijiazhuang 056000, china 4. Xizang Bureau of geology and Mineral Resources, Lhasa 850000, china chinese Acad Geol Sci Inst Mineral Resources Beijing 100037 Peoples R China chinese Acad Geol Sci Natl Ctr Geoanal Beijing 100037 Peoples R China Shijiazhuang Coll Econ Shijiazhuang 056000 Peoples R China Xizang Bur Geol & Mineral Resources Lhasa 850000 Peoples R China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.2.) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 2.—2. Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, institute of geology and Geophysics, {2. academy of sciences, beijing 10002., china 2. Graduate School of {2. academy of sciences, beijing 100039, china) [a]State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of {2. Beijing China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

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A New SHRIMP Age of the Xiamaling Formation in the North china Plate and Its geological Significance

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2.SHI Xiaoying~2.ZHOU Hongrui~2.WANG Ziqiang~2.SONG Biao~(1,3) 1 institute of geology,{2. academy of geological sciences,beijing 100037,china 2.9} University of Geosciences(beijing),beijing 100083,china 3 beijing SHRIMP Central,100037 beijing,china institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North china Plate,yielding a weighted mean;Pb/;U age of 1368±12.*** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North china Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding {2. evolution of the North china Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North china Plate

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Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3, GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of geology and Geophysics, {2. academy of sciences, beijing 10002., china 2. institute of Earth Environment, {2. academy of sciences, Xi’an 710075, china 3. institute of Geomechanics, chinese academy of geological sciences, beijing 100081, china 1. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1 m sequence varies from 6 to 13 μm and the > 63 μm fraction representsonly 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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Underplating in the middle-lower Yangtze Valley and model of geodynamic evolution:Constraints from geophysical data

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Science china Earth sciences 2005年第7期48卷 985-999页

作者： Lü Qingtian, HOU Zengqian, YANG Zhusen & SHI Danian institute of Mineral Resources,chinese {2. of geological sciences,beijing 100037,china institute of Mineral Resources Chinese Academy of Geoloqical Sciences Beijina 100037 China

The lower crust and Moho are the most active boundary layers in the process of continental evolution, in which marks left by tectonic and magmatic activities during the process are preserved. The evolutionary process of the continental lithosphere may be reconstructed by exploring the structures of the lower crust and Moho. According to a study of the deep seismic reflection data obtained from the middle-lower Yangtze Valley, the authors find bright layered reflections ubiquitous in the lower crust and think that the bright reflections are caused by un-derplating of basic or ultrabasic magmas, which might be related to delamination of the lithosphere. On the basis of an integrated analysis of the geophysical and geological data of the region, the authors propose a model for geodynamic evolution of the middle-lower Yangtze Valley. This model suggests that the middle-lower Yangtze Valley had undergone such geodynamic processes as collision-compression, delamination-extension and underplating-melting since the end of the Permian, finally forming the gigantic middle-lower Yangtze Valley metallogenic belt.

关键词： lower crust deep seismic reflection underplating tectonic evolution.

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Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2. , XIANG Jianhai 1*, WANG Bing 1,2. , LI Fuhua 1 and TONG Wei 3(1. Experimental Marine Biology Laboratory, institute of Oceanology, chinese {2. of sciences, Qingdao 2.6071,china 2. Graduate School of the chinese {2. of sciences, beijing 100039, china 3. Genomics & Bioinformatics institute, chinese {2. of sciences, beijing 101300, china) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

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Comparison of eastern paleo-Tethyan ophiolites and its geodynamic significance--Evidence from Dur'ngoi ophiolite

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Science china Earth sciences 2004年第4期47卷 378-384页

作者： CHEN Liang1,2. SUN Yong1,2. PEI Xianzhi2. Feng Tao2.& Zhang Guowei2.1. Open Laboratory of Continental Dynamics, Ministry of Education, Northwest University, Xi抋n 710069, china 2. institute of geology and Geophysics, {2. academy of sciences, beijing 10002., china Open Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an 710069 China institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Nd-Pb isotopic geochemistry of metabasalt from Dur抧goi ophiolite, Qinghai Prov-ince, NW china reveals the presence of DMM mixing with EMII components in its upper mantle source, which is comparable with present Indian MORB. Comparisons indicate that the geo-chemistry, chronology and source characteristics of Dur抧goi ophiolite coincide with Pa-leo-tethyan ophiolites from 揝anjiang?area. Together with evidences from regional geology in adjacent areas, this study proves that independent paleo-tethyan basins evolved contemporarily, the dynamics of which is attributed to the interaction of mantle plume with over-riding lithosphere.

关键词： ophiolite, Paleo-Tethys, DUPAL anomaly, Indosinian movement.

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