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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, {2. 100081, China 2. Institute of {2., chinese academy of geological sciences,{4., China 3. Institute of {2. and Geophysics, chinese academy of sciences, {2. 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, 4.Ar/3.Ar dating, late Cenozoic.

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 Laicheng{2.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of {3., Guangzhou 5106{2., China 2. Graduate University of chinese academy of {3., beijing 10003., China 3. SHRIMP isotope Laboratory,{12., beijing 10003., China {2. Institute of geology and Geophysics, chinese academy of {3., 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 {2. 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/2.0}U ages of 2.9.{2.± 3.0 Ma and 2.0}.{2.± 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/2.0}U age of 2.0}.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/2.0}U apparent age of 1977±{2. 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.

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science China Earth sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2. SONG Biao3.4. CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. {2. Surveying Institute of Hainan, Haikou 5702.6, China 2. Institute of Geomechanics, chinese academy of geological sciences, {3. 100081, China 3. {3. Center of SHRIMP,{4., China 4. Institute of geology, chinese academy of geological sciences,{4., China 1. geological Surveying Institute of Hainan 570206 Haikou China 2. Institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 3. beijing Center of SHRIMP 100037 Beijing China 4. Institute of geology Chinese Academy of Geological Sciences 100037 Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the beijing Ion-probe Center, acquire 2.6Pb/2.1}U ages of 3.8±3.5 Ma (of granite, 95% confidence level, MSDW=1.2.1} and 3.2.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04. respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

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,{2., beijing 10003., China 2. National Center of Geoanalysis,{2., beijing 10003., China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang Bureau of {4. 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 3.0 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 (1{2.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (1{2.0{2..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 (1{2.3.?.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.—2.0}Ma, and formed in a post-collision crustal ex-tension env

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

Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern China

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 365-379页

作者： Liu Xun Institute of geology, chinese academy of geological sciences, {2. chinese ACAD GEOL SCI INST GEOLBEIJINGPEOPLES R CHINA

Since Jurassic. intense and repeated tectonic movements have taken place in eastern China, of which theYanshanian movement is the most important. Thereby the development of the basins between the Jurassic andEogene in the studied areas may by divided into two different stages, i.e. the Yanshanian subcycle （J-K;） andthe North China subcycle （K;-E）. The basement and tectonic stress field of the basins played an obvious role in controlling thesedimentary-tectonic development of the basins. and down-faulted basins might form under different stressstates. Besides. the shearing stress also played an important part while the basins were forming in the notedareas.

关键词： Some Recognitions on the Sedimentary-Tectonic Development of the Meso-Cenozoic Basins in Eastern China

Zijinshan-Bitian Cu-Au-Mo orefield, SW Fujian——An example of gold-rich PCS zoning

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chinese Science Bulletin 1999年第S2期44卷 134-135页

作者： QI Jianzhong~1, LI Zhaonai~2. ZHANG Dequan~3. FANG Xiheng~4.and XIAO Huiliang~1 1. Nanjing Institute of {2. and Mineral Resources, chinese academy of geological sciences, Nanjing 2.0016, China 2. Institute of {2., chinese academy of geological sciences,{4., China 3. Institute of Mineral Deposits, chinese academy of geological sciences,{4., China 4. Institute of {2., Ministry of Nuclear Industry, {12. 100013. China Nanjing Institute of geology and Mineral Resources Chinese Academy of Geological Sciences Nanjing 210016 China Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China Institute of geology Ministry of Nuclear Industry Beijing 100013 China

THE Zijinshan-Bitian Cu-Au-Mo orefield is spread to north of the Shanghang County, SW *** geological structure it is located at the plunging end of NE-trending Xuanhe anticlinorium, in the NE rim ofthe NW trending Shanghang volcano-sedimentary basin. Orefield basement is composed of the Archean-Middle Proterozoic low-grade metamorphic rock formations, containing marine basic metavolcanic sequenses. Lower Cretaceous subaerial volcanic rocks of andesite-trachy andesite-rhyolite composition fill inthe volcano-sedimentary basin. Pre-mineralization granitic batholith dated 14.Ma（Rb-Sr）and 157Ma（U-Pb） occupies the axial part of the plunging anticlinorium, which was regarded as crust-remelting typegranitoids. Mineralization-affiliated subvolcanic dacite porphyrite, co-volcanic granodiorite and quartzdiorite porphyrite （102.2.Ma（Rb-Sr）, Sr1 = 0.708 9） belong to syntactic type in genesis and

关键词： gold-rich porphyre copper system zoning Fujian Zijinshan.

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, chinese academy of geological sciences, beijing 10003., China 2. Key Open Laboratory of Saline Lake Resources and Environment, chinese academy of geological sciences, beijing 10003., China 3. Institute of Mineral Resources, chinese academy of geological sciences, beijing 10003., China R&D Center for Saline Lake Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China Key Open Laboratory of Saline Lake Resources Environment Chinese Academy of Geological Sciences Beijing 100037 China Institute of Mineral Resources 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 (2.0}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.

Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en Institute of geology, chinese academy of geological sciences, {2. Liu Linqun Institute of geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science China Earth sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3. LI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. Institute of geology and Geophysics, {2. {2. of {3., {4. 10002., China 2. Institute of Geophysics, {2. Seismological Bureau, {4. 100081, China 3. Institute of Deposition Resource, chinese academy of geological sciences, beijing 10003., China 1. Institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 4. km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

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. {2. of {3., {4. 10002., China 2. Institute of Earth Environment, {2. {2. of {3., Xi’an 710075, China 3. Institute of Geomechanics, chinese academy of geological sciences, {4. 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.