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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 {3., Beijing 100081,{4. 2. institute of geology, Chinese academy of geological {3., Beijing 10003.,{4. 3. institute of geology and Geophysics, Chinese academy of {3., Beijing 100029,{4. 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 Laicheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese academy of {3., Guangzhou 51064., china 2. Graduate University of Chinese academy of {3., Beijing 10003., china 3. SHRIMP isotope Laboratory, Chinese academy of geological {3., Beijing 10003., china {13. and Geophysics, Chinese academy of {3., Beijing 100029, 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 (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4.± 3.0 Ma and 23..4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/23.U age of 23..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 (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±4. 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. geological Surveying institute of Hainan, Haikou 570206,{3. 2. institute of Geomechanics, Chinese {4. of geological sciences, Beijing 100081,{3. 3. Beijing Center of SHRIMP, Beijing 10003.,{3. 4. institute of geology, Chinese {4. of geological sciences, Beijing 10003.,{3. 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 206Pb/23.U ages of 3.8±3.5 Ma (of granite, 95% confidence level, MSDW=1.23. 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.

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, Chinese {3. of sciences, Nanjing 210008,{4. 2. Henan institute of geological Survey, Zhengzhou 4.0007,{4. 3. State Key Laboratory of geological Processes and Mineral Resources at{4. University of Geosciences, Wuhan 4.0074.{4. 4. Faculty of Material sciences and Chemical Engineering,{4. University of Geosciences, Wuhan 4.0074.{4. 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 Mineral Resources 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.

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2, LI Anchun1, HU Ningjing2,3. FU Yongtao1& MA Zhibang4.1. institute of Oceanology, Chinese academy of {3., Qingdao 266071, china 2. Graduate School of the Chinese academy of {3., Beijing 10003., china 3. institute of Soil Science, Chinese academy of {3., Nanjing 210008, china 4. institute of geology and Geophysics, Chinese academy of {3., Beijing 100029, china 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate School of the Chinese academy of sciences Beijing 100039 China 3. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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Science china Earth sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2, YU Haifeng3. YE Haimin2, ZHAO Yu2 & ZHANG Dongsheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese academy of {3., Guangzhou 51064., china 2. Nanjing institute of geology and Mineral Resources, Nanjing 210016, china 3. Tianjin institute of geology and Mineral Resources, Tianjin 3.0170, china 4. The 2nd Regional {13. Investigation Party, Xinjiang Bureau of geology and Mineral Resources, Changji 83.100, china 1. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 2. Nanjing institute of geology and Mineral Resources Nanjing 210016 China 3. Tianjin institute of geology and Mineral Resources Tianjin 300170 China 4. The 2nd Regional geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 831100 China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 3.0.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4.and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3.0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2DM model ages of 4.0 to 580 Ma and positive εNd(3.1 Ma) values of 6.23.to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

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 geology and Mineral Resources, Chinese {3. of geological {4., Nanjing 210016, china 2. institute of geology, Chinese {3. of geological {4., Beijing 10003., china 3. institute of Mineral Deposits, Chinese {3. of geological {4., Beijing 10003., china 4. institute of geology, Ministry of Nuclear Industry, Beijing 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.

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 {3. sciences, Beijing 10003.,{4. 2. National Center of Geoanalysis, Chinese academy of {3. sciences, Beijing 10003.,{4. 3. Shijiazhuang College of Economy, Shijiazhuang 056000,{4. 4. Xizang Bureau of geology and Mineral Resources, Lhasa 850000,{4. 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 (14.76?.22) 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 (14.3.?.22) 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 21—23.Ma, and formed in a post-collision crustal ex-tension env

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

Experimental study of ore gabbro liquid immiscibility

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Science china Earth sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3.& JIN Zhenmin4.1. Guangzhou institute of Geochemistry, Chinese academy of {3., Guangzhou 51064., china 2. Wuhan University, Wuhan 4.0072, china 3. institute of geology, china Seismological Bureau, Beijing 100029, china 4. Faculty of Earth {3., china University of Geo{3., Wuhan 4.0074. china 1. Guangzhou institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan University 430072 Wuhan China 3. institute of geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

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 {3. {4., Beijing 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