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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 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 Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China nanjing institute of geology and mineral resources Nanjing China Tianjin institute of geology and mineral resources Tianjin China The 2nd Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 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 330.7±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 470 to 580 Ma and positive εNd(331 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.

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 550025, china nanjing institute of geology and mineral resources, nanjing 210016, china Geological Survey of No. 3 Geological Party, Xinjiang, Kurle 841000, china) Postgraduate School of Guizhou University Guiyang 550025 China nanjing institute of geology and mineral resources Nanjing 210016 China Geological Survey of No. 3 Geological Party Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3-1. 4 mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

The geological feature, geochemistry and origin of Jinya gold deposit in Fengshan, Guangxi

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Chinese Science Bulletin 1999年第S2期44卷 168-169页

作者： ZHOU Jiyuan~1, CUI Bingfang~1 and LU Yan~2 1. nanjing institute of geology and mineral resources, nanjing 210016, china 2. Chengdu institute of Technology, Chengdu 610059, china nanjing institute of geology and mineral resources Nanjing 210016 China Chengdu institute of Technology Chengdu 610059 China

1 Geological feature of deposit The Jinya gold deposit is a fine disseminated gold mine. It occurs in sandstone and mudstone ofMiddle-Triassic Baifeng Formation, which is located at the margin of Late Paleozoic carbonate platform. Itwas controlled by the fracture zone, cleavage zone and fissure zone. The gold deposit has 15 orebodies,which are displayed as beds, lens and veins. The dominating minerals with gold are pyrite and arsenopyrite. The gold mainly occurs as submicroscopic intergranular gold. Low-to-moderate temperature (130-305℃) wall-rock alterations are mainly silicification, pyritization and arsenopyrite, also includes realgarization, carbonation (calcite, dolomite), sericitization and argillation (kaolinite, pyrophyllite). It wasformed after undergoing the sedimentary diagenetic period, hydrothermal mineralization epoch (213 Ma)and supergene mineralization.

关键词： geological feature Jinya gold deposit Fengshan.

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth Sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4, WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, china 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, china 3 nanjing institute of geology and mineral resources, nanjing 210016, china 4 State Key Laboratory of Loess and Quaternary geology, institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china 5 State Key Laboratory for mineral Deposits Research, Department of Earth Sciences, nanjing University, nanjing 210093, china Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China nanjing institute of geology and mineral resources Nanjing China State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China State Key Laboratory for mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

Genesis and geological charateristics of Songxi Ag-Sb ore deposit in Guangdong

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Chinese Science Bulletin 1999年第S2期44卷 80-81页

作者： XIAO Huiliang, FU Dexin and QI Jianzhong nanjing institute of geology and mineral resources, nanjing 210016, china

THE Songxi Ag-Sb ore deposit is situated 28 km northeast of Meizhou city in Guangdong. It is on thenorth edge of the volcanic fault depression of the Saigangshang, which belongs to the upper Palaeozoicfault basin belt of Yong’an-Meizhou, and at the intersection of Dadong-Guidong-Jiaoling EW fault zone,Lianhuashan-Heyuan NE fault zone and Jiaoling-Shantou NW fault zone. Ag-Sb ore body occurs at thebottom of the upper part of the lower Jurassic Jingji Group (Jlje-l), which is a formation of detrital rocksconsisting mainly of carbonaceous shale. 1 Geological characteristics of the ore

关键词： genesis geological characteristics Songxi Ag-Sb ore deposit.

Preliminary Study on Deep geology of Dabie Orogenic Belt

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Continental Dynamics 1996年第2期 103-108页

作者： Dong Shuwen (nanjing institute of geology and mineral resources, CAGS, nanjing 210016, china)Wu Xuanzhi (institute of mineral Deposits, CAGS, Beijing 100037, china)Gao Rui Lu Deyuan (institute of geology , CAGS, Beijing 100037, china)Li Yingkang (562 Co

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关键词： wide-angle seismic reflection deep geology orogernic belt Dabie Mountains

RESEARCH ON THE PRE-MESOZOIC BASE STRATA OF VOLCANIC ROCK SERIES IN EASTERN ZHEJIANG PROVINCE,china

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RESEARCH ON THE PRE-MESOZOIC BASE STRATA OF VOLCANIC ROCK SE...

Lasing on pyroclastic rocks:A case study of 40Ar/39Ar dating on Moshishan Group,eastern Zhejiang Province

International Conference of mineralization in Precambrian Terranes & Unesco/Iugs Igcp 443 Annual Meeting and Field Correlation 2003

作者： Ying-Ping WANG, Mai-Ping QIAN, Yong-Kui YAN, and Bao-Liang DING (nanjing institute of geology and mineral resources, nanjing 210016, china)

Mesozoic volcanic rock series occupied widely in eastern Zhejiang Province located in tectonomagrnatic activity belt of West Pacific *** which, the main dark light metamorphic sedimentary strata sequence in near Yongjia City were correlated with Upper Jurassic "a" section of Zhuji Formation （JZ）, Chawan Formation （Jc）, or Lower Cretaceous Guantou Formation （Kg） for long,because of absence of a fossil ***, we found in first time abundant micropalaeophyta fossils in numerous levels of the sequence, and believe it to be of the Sinian.

关键词： Neoproterozoic micropalaeophyta fossils, eastern Zhejiang

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Lasing on pyroclastic rocks:A case study of 40Ar/39Ar dating...

中国科学院地质与地球物理研究所2008学术年会

作者： YANG LieKun~(1,2+),WANG Fei~1,SHEN JiaLin~3,CHEN Rong~3 &XING GuangFu~3 1 State Key Laboratory of Lithospheric Evolution,institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3 nanjing institute of geology and mineral resources,nanjing 210016,china

It is difficult to date pyroclastic rocks,for almost all the dating methods,due to the multiple sources during their ***/Ar incremental heating results on groundmass selected from the samples show that the age spectra are meaningless ***,singe crystal total fusions of CO lasing on the sanidine separates could yield rational Ar/Ar results and distinguish their sources in this *** on three formations of the Moshishan Group,after avoiding the exotic and altered grains by lasing on the single sanidine separate,was reported in this *** lowermost portion of the Chawan Formation gives an age of 113.7±0.3 Ma;the lower part of the Xishantou Formation was formed 116.4±0.4 Ma ago and the bottom of the Gaowu Formation took its shape at 118.4±0.4 *** new ages are much younger than the previous ones,suggesting that these thick volcanic formations had been formed in very short durations.

关键词： pyroclastic rocks CO2 laser sanidine grain 40Ar/39Ar dating the Moshishan Group

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试论江苏地质遗迹保护和利用

江苏地质 2004年第3期28卷 129-133页

作者：陶奎元岳文浙谢家莹沈加林南京地质矿产研究所江苏南京210016

地质遗迹是地球 4 6亿年演化留给人类的宝贵财富 ,基于对江苏省地质遗迹的鉴评 ,提出申报建设地质公园与地质遗迹保护区 ,推行“科学在公园”计划 ,建立地球科学野外露天教室 ,开拓地学知性之旅等作为保护和利用地质遗迹的举措与相关建议。

关键词：地质遗迹保护利用举措江苏