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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

Science china Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4, TAN Hongbing2.& WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary geology, institute of Earth Environment, {2. Academy of sciences, Xi’an 710075 china 2. Qinghai institute of Salt Lakes, {2. Academy of sciences. Xining 810008, china 3. institute of geology and Geophysics, {2. Academy of sciences, beijing 10002., china 4. Department of Geography, Qinghai Normal University, Xining 810008, china chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14, 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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Effect and mechanism of stresses on rock permeability at different scales

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Science china Earth sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2.1. Safety Engineering College, North china institute of Science and Technology, Yanjiao, {2. 101601, china 2. Key Laboratory of Geophysics Exploration, china University of Petroleum, {2. 100083, china 1. Safety Engineering College North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of Geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2. At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

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The continental hydrothermal sedimentary origin of the Dashui superlarge gold deposit in Gansu Province, china

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chinese Science Bulletin 1999年第S2期44卷 210-212页

作者： LI Hongyang~1, YANG Zhusen~1, GAO Zhenmin~1, LUO Taiyi~1, DING Zhenju~1 and YAN Shenghao~2.1. institute of Geochemistry, chinese Academy of {2., Guiyang 550002. china 2. institute of Mineral Deposits, chinese Academy of geological {2., beijing 100037, china institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China

THE Dashui gold mine, situated in Gansu Province of western china, is a superlarge gold deposit newlydiscovered in western Qinling erogenic belt, hosted within the Permian-Triassic limestones and dolomites,as well as Jurassic conglomerates. It has been termed Carlin-type and hot spring-type gold ore, yet its origin is enigmatic. It is characterized by the formation of sedimentary and replacement bodies of hematite-hydrothermalsiliceous rocks above and adjacent to orebodies. The orebodies themselves exhibit a variety of geometries,such as funnels, pipes, sack-like, tabular zones parallel to bedding. NWW-EW striking, nearly SNstriking and NEE-NE striking faults control the ore-fluid passages. The orebody sites and shapes arelargely controlled by the intersection of such different strike faults. The ore mineral assemblage is characteristically gold-hematite-chalcedony. The gold mineralizationand hematitization and silification are closely interrelated. Five basic ore types are recognized: laminated-

关键词： continental hydrothermal sedimentation superlarge gold deposit Dashui Gansu.

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geological EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU

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地学前缘 2000年第S1期7卷 234-235页

作者： Xu Zhiqin, Yang Jingsui, Li Haibing(institute of geology, {2. Academy of geological sciences, beijing 100037,china)

The East Kunlun terrain is located on the northern Qinghai—Tibet plateau, composed of the East Kunlun Mountain and the Qaidam Basin and bounded by the Qilian terrain on the north and Bayanhar—Songpan Ganze terrain on the south. It is regarded as a composite orogenic belt characterized by having developed superimposed ductile tectonic regimes reflecting the collision orogeny during Early Paleozoic and Triassic periods. It has also experienced transformation from ductile to brittle deformation caused by the post orogeny, since Jurassic after the formation of the East Kunlun Mountain and the Qaidam Basin. A Paleozoic subduction complex zone was recently recognized along the north border of the East Kunlun terrain from Da Qaidam to Dulan (Xu,et al, 1 999). It is composed of ophiolite (of Early Paleozoic age?), tectonic melange and very high\|pressure metamorphic rocks with eclogite (\%p\%=2.2.Pa, \%t\%=72.℃) (Yang,et al.,1998) and garnet\|peridotite (\%p\%=2.5GPa, t =837℃). The Anyemaqin Triassic subduction complex zone trending in NWW\|SEE was developed along the eastern segment of the south border of the East Kunlun terrain. It is mainly composed of ultramafic and mafic rocks, pillow basalt, radiolaria\|bearing clastic rocks, tectonic melange and mylonite. The subduction complex zone contains a series of the southward overthrusting imbricated slices. Instead of this subduction complex zone, a 2.km\|wide sinistral strike\|slip ductile shear zone trending in E\|W was developed along the western segment. On the basis of macroscopic and microscopic studies on a series of structural sections, we divide the East Kunlun Mountain into four tectonic units as follows: (1) North Proterozoic Metamorphic Basement Zone; (2. South Early Paleozoic—Triassic Superimposed Fold Zone; (3) South Triassic Transpression Zone; (4) Anyemaqin Back\|Arc Decollement\|Thrust Zone.

关键词： East Kunlun terrain composite orogenic belt subduction compl ex zone transpression shear zone

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Yixunite and Damiaoite—A Twin of New Native Alloys of Indium and Platinum from the Yanshan Mountains

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 480-485,512-513页

作者： Yu Zuxianginstitute of geology, {2. Academy of geological sciences, 2. Baiwanzhuan, beijing 100037 institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuan Beijing 100037 [?]Yu Zuxiang Born in 1930 graduated from the Specialty of Mineralogy and Petrology Beijing College of Geology in 1953 now Research Professor of the institute of geology Chinese Academy of Geological Sciences having long engaged in the study of mineralogy.

Yixunite and damiaoite Were found in a cobalt- and copper-bearing platinum ore vein of a contact metasomatic deposit. The chief ore minerals are bornite, chalcopyrite, magnetite and carrollite. The platinum minerals include moncheite, sperrylite, daomanite, cobalt malanite and cooperite. Yixunite and damiaoite occur as immiscible globules, 1.0 to 2.0 mm in diameter. Yixunite is always in the central part of a globule. It is opaque with metallic lustre, bright white colour and black streak. HM = 5.8; VHN50 = 634 kg/mm2.(573-681 kg/ mm2.; insoluble in HCl, HNO3, HF or H3PO4; no cleavage; no magnetism. Density is hard to measure because of small grain size. Calculated density = 18.2. g/cm3. Reflective colour is bright white with a yellowish tint. Isotropic. The mean analytical results (ranges) (%) are: Pt 82.8 (81.8-83.6), In 16.4(15.6-17.1) and total 99.2. The empirical formula (based on 4 atoms) is Pt2.993 In1.007 . The five strongest lines of X-ray diffraction (hkl, d,I) are 111, 2.30 (100); 2.0, 1.99 (60); 2.2. 1.411 (40);311, 1.2.3 (80); 2.2. 1.151(40). Space group: Pm3m with a =0.3988(3) nm and Z= 1. Damiaoite occurs as single globules or was exsolved from yixunite. Opaque with metallic lustre; bright white colour with black streak; HM = 5.3; VHN50 = 485 kg/mm2.(434-52. kg/mm2.; insoluble in HC1, HNO3, HF or H3PO4; cleavage: no; magnetism: no. Density: hard to measure because of small grain size. Calculated density = 10.95 g/ cm3. Reflective colour is bright white with a yellowish tint. Isotropic. The mean analytical results (ranges) (%) are Pt 45.6 (45.4-46.0), In 53.5 (52.4-53.9), total 99.1. The empirical formula (based on 3 atoms) is Pt0.002.In1.998. The six strongest lines of X-ray diffraction (hkl.d,I) are 2.0,2.2. (100); 311,1.92.(60); 400,1.59 (60); 42.,1.2.9 (80); 440,1.12. (60); 62.,1.006 (70). Space group: Fm3m with a = 0.6364 (3) nm and Z = 4.

关键词： yixunite damiaoite new native alloys cobalt- and copper-bearing platinum ore vein contact metasomatic deposit

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PALEOMAGNETIC ESTIMATE OF THE MESOZOIC—CENOZOIC LATITUDINAL DISPLACEMENT OF TERRENES IN THE QINGHAI—TIBET PLATEAU AND ITS SIGNIFICANCE

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地学前缘 2000年第S1期7卷 325-326页

作者： Li Pengwu, Cui Junwen, Li Li(institute of geology, {2. Academy of geological sciences, beijing 100037, china)

The Mesozoic—Cenozoic latitudinal displacement amounts of terranes (or blocks) in the Qinghai—Tibet plateau were calculated in paleomagnetism. These terranes (or blocks) include Tarim and Qaidam blocks, East Kunlun, Baryan Har, Qiangtang, Lhasa and Himalaya terranes. The calculated results are listed in table 1. These results show that:(1) There was the latitudinal displacement difference between central area and southwestern area in the Tarim southern margin since the lower Cretaceous. There was a southward latitudinal movement from the beginning of middle Jurassic or upper Jurassic (Zhou Qingjie, 1992.. The northward movement amounts of the Tarim northern margin since the Paleocene are greater than that of the Tarim southern margin. Tarim southern margin has moved northward about 1100km since the Paleocene, Tarim northern margin has done about 1700km. Qaidam has moved northward about 3100km since lower\|middle Jurassic. The northward displacement amount of Qaidam since Paleocene is about 810km, near to that of the central area, Tarim southern margin.

关键词： Qinghai\|Tibetan plateau paleomagnetism latitudinal displacement

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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3 & DENG Jun1 1 State Key Laboratory of geological Processes and Mineral Resources,china University of Geo{2.,beijing100083,china 2.Laboratory of Nuclear Analysis Techniques,institute of High Energy Physics,chinese Academy of {2.,beijing 100039,china 3 Department of geology,Peking University,beijing 100871,china 1. State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―350℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132.Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

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Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2.3 1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese Academy of Fishery sciences, Qingdao 2.6071,{2. 2. institute of Oceanology, chinese Academy of sciences, Qingdao 2.6071,{2. 3. The Graduate School of the chinese Academy of sciences, beijing 100039,{2. Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China The Graduate School of the chinese Academy of sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2.59 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 2..6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2. of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42.. In decreasing order, the 2. most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (2.4), AAT (92., A (56), AAG (2.), ATC (2.), ATAG (2.), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

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Changchengite—A New Iridium Bismuthide-Sulphide from the Yanshan Mountains

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 486-490,514页

作者： Yu Zuxianginstitute of geology, {2. Academy of geological sciences, 2. Baiwanzhuang, beijing 100037 institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 [?]Yu Zuxiang Born in 1930 graduated from the Specialty of Mineralogy and Petrology Department of Geology Beijing College of Geology in 1953 now research professor at the institute of geology Chinese Academy of Geological Sciences. He has long engaged in the study of mineralogy geochemistry and mineral deposits related to ultrabasic rocks. He is a member of the Committee on New Minerals and Minerals Names of GSC.

Changchengite occurs in chromite orebodies in dunite and in platinum placer deposits in chromite orebodies nearby. The mineral occurs as massive aggregates or veinlets on margins of iridisite (IrS2. and replaces it. Opaque. Lustre metallic. Colour steel-black. Streak black. Hm = 3.7. VHN2.= 165 kg/ mm2. Isotropic. Cleavage none. Density 11.96 g/ cm3. Seven electron microprobe analyses give the following mean chemical results (wt. %): S 7.2. Cu 0.3, Te 0.4, Ir 41.2. Pt 2.8 and Bi 47.3 with total 99.1. The simplified formula is IrBiS. The strongest X-ray powder diffraction lines (hkl, d, I) are 2.0, 2.75 (70); 2.1, 2.51 (60); 311, 1.860 (100); 440. 1.090 (50) and 600, 1.02. (50). The X-ray powder diffraction pattern is similar to that of mayingite. After the diffraction data are indexed the mineral is determined to be cubic. The space group is P2.3 with a = 0.6164(4) nm, V = 0.2.42.nm3 and Z = 4.

关键词： changchengite new mineral new iridium bismuthide-sulphide Yanshan Mountains chromite ore body platinum placer deposit

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Petrology of the Non-mafic UHP Metamorphic Rocks from a Drillhole in the Southern Sulu Orogenic Belt,Eastern-Central china

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Acta Geologica Sinica(English Edition) 2003年第2期77卷 173-186页

作者： ZHANG Zeming, XU Zhiqin and XU Huifeninstitute of geology, {2. Academy of geological sciences, 2. Baiwanzhuang Rd., beijing 100037 E-mail: zzm@***. institute of geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Rd. Beijing 100037

The Drillhole ZK703 with a depth of 558 m is located in the Donghai area of the southern Sulu ultrahigh-pressure (UHP) metamorphic belt, eastern china, and penetrates typical UHP eclogites and various non-mafic rocks, including peridotite, gneiss, schist and quartzite. Their protoliths include ultramafic, mafic, intermediate, intermediate-acidic, acidic igneous rocks and sediments. These rocks are intimately interlayered, which are meters to millimeters thick with sharp and nontectonic contacts, suggesting in-situ metamorphism under UHP eclogite facies conditions. The following petrologic features indicate that the non-mafic rocks have experienced early-stage UHP metamorphism together with the eclogites: (1) phengite relics in gneisses and schists contain a high content of Si, up to 3.52.p.f.u. (per formula unit), while amphibolite-facies phengites have considerably low Si content (2. p.f.u.); (2. jadeite relics are found in quartzite and jadeitite; (3) various types of symplectitic coronas and pseud

关键词： UHP metamorphism non-mafic rock drillhole Dabie-Sulu orogenic belt eastern-central china

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