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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 3.0170, china 4. The 2nd Regional Geological Investigation Party, Xinjiang Bureau of geology and Mineral resources, Changji 83.100, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China nanjing institute of geology and Mineral {3. 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 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 470 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.

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The modes of gold-migration in the gossan-type gold deposit

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Chinese Science Bulletin 1999年第S2期44卷 32-33页

作者： HE Jurui and LI Ying nanjing institute of geology and Mineral {3., nanjing 210016, china nanjing institute of geology and Mineral {3. Nanjing 210016 China

MORE than 3. gossan-type gold deposits have beed discovered in the Middle-Lower Yangtze River *** profile of gold-bearing gossan can be divided into four subzones from upper to lower: （i） gold-deficient or gold-leached gossan (Au contents （0.1-0.8）×10-6) transitonal subzone; （ii） secondary goldconcentration subzone (Au（4-20）×10-6); （iii） oxide and sulfide transitional subzone (Au（0.5-1.5）× 10-6); （iV） Primary sulfide ore (Au（0.5-1） × 10-6). Au Concentration in the subzone （ii） is 2-20 times higher than that in subzone （iV）. Obviously migration and secondary concentration of Au hadhappened in the process of oxidation of primary sulfides. Some geologists indicated that there would be four modes of gold-migration and concentration:（1） gravity separation （mechanism）; （2） organic complex or adsorption; （3. colloidal

关键词： gold migration gossan-type gold deposit.

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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 {3. 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 {3. 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.

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Geochronology and Geochemical Characteristics of the Early Mesozoic Tangquan Pluton in Southwestern Fujian and Its Tectonic Implications

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Acta Geologica Sinica(English Edition) 2003年第3期77卷 361-371页

作者： MAO Jianren, HU Qing, XU Naizheng, XIE Fanggui and TAO Kuiyuan, nanjing institute of geology and Mineral {3., nanjing, Jiangsu 210016 E-mail: mjrmh@*** Hao Ziguo and Zhu Xiling nanjing Inst Geol & Mineral resources Nanjing 210016 Jiangsu Peoples R China

The Tangquan granodioritic pluton in Dalian County, southwestern Fujian, china, which extends in a NE direction with an exposed area of about 13. km2, used to be considered a product of Early Cretaceous magmatism. The present study suggests for the first time that the pluton was formed in the Early Jurassic by using multiple methods for isotopic dating, which give zircon U-Pb ages of 186.8 Ma and 179.0 Ma, Rb-Sr isochron age of 162.02±4.5 Ma, and biotite 40Ar/3.Ar plateau age of 158.1±0.7 Ma. The cooling rate for the pluton was relatively low (4.76℃/Ma) during the early stage (183.162 Ma) because of the compressional environment. It was emplaced in a higher cooling rate (50℃/Ma) in an extensional environment during the later stage (162-158 Ma). The granodiorites are metaluminous-peraluminous, relatively enriched in Na2O and depleted in K2O, and characteristic of I-type granites of crust-mantle mixed sources. They are moderately enriched in Rb, Th, Hf and LREE, and depleted in Ti, Nb, Ta and Sr, and have geochemical features of cal-alkaline rocks of an island arc or active continental margin. Their (87Sr/86Sr)i ratio varies from 0.70769 to 0.70822, εNd(t) from -9.68 to -10.07 and TDM from 1.52 to 1.55 Ga. They were formed by mixing of mantle-derived mafic magma with the granitic magma resulting from partial melting of crust-derived materials in an upwelling of the asthenospheric mantle in South china during the Early Mesozoic.

关键词： granodiorite Early Jurassic petrogenesis tectonic setting southwestern Fujian china

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Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2 & ZHENG ShaoLin 3.1 nanjing institute of geology and Palaeontology,Chinese Academy of Sciences,nanjing 210008,china 2 Fairy Lake Botanical Garden,Shenzhen 518004,china 3.Shenyang institute of geology and Mineral resources,Shenyang 11003.,china nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Fairy Lake Botanical Garden Shenzhen China Shenyang institute of geology and Mineral resources Shenyang China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性

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Sources of Cretaceous Bimodal Volcanic Rocks in the Coastal Region of Southeastern china -- Constrains of the Sr content and its isotopes

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 84-92页

作者： XING Guanfu YANG Zhuliang and TAO Kuiyuan nanjing institute of geology and Mineral {3., Chinese Academy of Geological Sciences,53. East Zhongshan Road, nanjing 210016 Chinese Acad Geol Sci Nanjing Inst Geol & Mineral Resources Nanjing 210016 Peoples R China

Cretaceous volcanism in the coastal region of southeastern china was characteristized by occurrenceof bimodal volcanics consisting of basalts and rhyolites, the geneses of which are still controversial. Based on the factthat their isotopic compositions are similar but the Sr content of the former is much higher than that of the latter, thispaper discusses the respective sources of the two end-member rocks, and concludes that basalts were derived fromthe subduction-related enriched upper mantle wedge and their isotopic compositions had not been affected by crustalassimilation, whereas rhyolites were formed by remelting of the old metamorphic basement, but they were mixed upwith the underplating basaltic magmas to various degrees so that their Sr isotopic compositions varied significantlyfrom the sources and tended to be homogeneous to the latter.

关键词： Sr content and its isotopes Cretaceous bimodal volcanics coastal region of southeastern china

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Flow Pattern and Heat Transfer Behavior of Boiling Two-Phase Flow in Inclined Pipes

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Journal of Thermal Science 1992年第3期1卷 196-202页

作者： Liu Dezhang Ouyang Ning nanjing Aeronautical institute, 210016 nanjing, china nanjing Aeronautical institute Nanjing China

Movable Electrical Conducting Probe (MECP), a kind of simple and reliable measuring transducer, used for predicting full-flow-path flow pattern in a boiling vapor/liquid two-phase flow is introduced in this paper. When the test pipe is set at different inclination angles, several kinds of flow patterns, such as bubble, slug, churn, intermittent, and annular flows, may be observed in accordance with the locations of MECP. By means of flow pattern analysis, flow field numerical calculations have been carried out, and heat transfer coefficient correlations along full-flow-path derived. The results show that heat transfer performance of boiling two-phase flow could be significantly augmented as expected in some flow pattern zones. The results of the investigation, measuring techniques and conclusions contained in this paper would be a useful reference in foundational research for prediction of flow pattern and heat transfer behavior in boiling two-phase flow, as well as for turbine vane liquid-cooling design.

关键词： liquid/vapor two phase flow inclined pipes flow patterns heat transfer coefficient.

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A sort of iron-manganese nodule developing in drowned platform margin

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Chinese Science Bulletin 1999年第S2期44卷 34-35页

作者： JIANG Yuehua, YE Zhizheng and YUE Wenzhe nanjing institute of geology and Mineral {3., Chinese Academy of Geological Sciences, nanjing 210016, china nanjing institute of geology and Mineral {3. Chinese Academy of Geological Sciences Nanjing 210016 China

A sort of purplish red iron-manganese nodules was found in the Middle Ordovician Guniutan-Miaopu period limestone, Anhui Province. About their formational environment, there are two different viewpoints:Yue thought they were deep-water pelagic deposit and Huang et al. believed they were formed inshallow water tide. We think that these nodules were formed in drowned platform margin belonging to atransitional type between shallow-water and deep-water iron-manganese nodules, and different from shoalwater iron-manganese oolites and pelagic iron-manganese nodules in feature and origin. 1 Palaeogeographic setting of iron-manganese nodules

关键词： iron-manganese nodule drowned platform platform margin.

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Computer Aided Analysis of Nonlinear Distortion for Laser Diode under Intensity Modulation

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Chinese Journal of Lasers 1997年第5期B6卷 391-396页

作者： ZHANG Zhengxian (Communicatins Engineering institute, nanjing 210016, china)HU Gang (Southeast University, {3. 210018, china) Communications Engineering Inst Nanjing China

A large signal equivalent circuit model is set up by using normalized rate equations and the practical method to analyze nonlinear distortion for laser diode applying PSPICE is discussed. Simulated results match well ... 详细信息

关键词： laser diode equivalent circuit model nonlinear distortion

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Lower Cretaceous angio-sperm leaf from Wuhe in Anhui,china

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Chinese Science Bulletin 2003年第6期48卷 611-614页

作者： LI Haomin nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China

A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 cm both in length and in width. The leaf veins are well preserved and clearly visible under a low power microscope. Leaf ar-chitectural analysis shows that such a leaf should belong to the first leaf rank of Hickey, i.e. the most primitive one. There are no early angiosperm leaves published completely similar to ours. A new species name of Dicotylophyllum minutissimum sp. nov. is established for the present leaf fos-sils.

关键词：安徽下白垩统早期被子植物叶片结构叶片化石

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