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Himalayan Tectonic Evolution in the East Asian Peri-Pacific Region

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 233-246页

作者： Cui Shengqin Li Jinrong institute of Geomechanics, Chinese Academy of geological Scinences, Beijing fei zhenbi institute of Geornechanics Chinese Academy of Geological Scinences Beijing

This paper summarizes the Late Palaeozoic. Indosinian and Yanshanian palaeotectonic settings in theperi-Pacific region of East Asia. On that basis, the Himalayan crustal movement in the region is divided intothe early and late tectonic stages and two principal tectonic phases. From the ocean to the continent, 5 giganticHimalayan formation-deformation belts are distinguished; they are the Northwest Pacific trench-island arcbelt. the Northwest Pacific marginal sea basin bell. the East China Sea-northern South China Seacontinental-shelf down-faulted belt. the East Asian epicontinental rift belt. and the East Asian intracontinentalrift belt. The Early and Late Himalayan tectonic evolution is dealt with. Finally the state of the Himalayan re-gional stress field and its evoution in the region are discussed. It is considered that the mechanism of their for-mation is closely related to the continent-ocean and surface-deep earth interaction.

关键词： Asia

The Evolution of Alpine Ultramafic Rocks and Partial Melting of the Upper Mantle

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 43-61,122页

作者： Bao Peisheng, Wang Xibin, Hao Ziguo and Peng Genyong institute of Geology, Chinese Academy of geological sciences, Beijing fei zhenbi institute of Geology Chinese Academy of Geological Sciences Beijing

Ultramafic rocks of Tibet and Xinjiang are the products of partial melting of the upper mantle. The evolution of their mineral composition is marked by two parallel evolutionary series: one is the progressive increase of the 100 Mg/(Mg+Fe^(2+) ratio of silicate minerals in order of lherzolite→harzburgite→dunite, i.e. the increase in magnesium; the other is the increase of the 100 Cr/(Cr+Al) ratio of accessory chrome spinel in the same order, i. e. the increase in Chromium. The above-mentioned evolutionary trends are contrary to that of magmatic differentiation. The evolution of fabrics of ultramafic rocks is characterized by progressive variation in order of protogranular texture→melted residual texture, symplectic texture and clastophyritic texture→equigranular mosaic texture and tabular mosaic texture. Experiments of partial melting of lherzolite have convincingly shown that the evolution of Alpine ultramafic rocks resulted from the partial melting of pyrolite. Various subtypes of them represent different degrees of partial melting. The vertical zoning marked by more basic rocks in the upper part and more acid rocks in the lower actually belongs to the fusion zoning of pyrolite.

关键词： Alpine ultramafic rocks upper mantle partial melting

Geochemistry of a Rapakivi Granite Suite in a Proterozoic Rift Trough in Beijing and Its Vicinity

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 169-186页

作者： Yu Jianhua fu Huiqin Zhang Fenglan Guan Meisheng Beijing Centre of geological Research and Laboratory fei zhenbi Beijing Centre of geological Research and Laboratory

Controlled by E-W-trending faults, a Proterozoic (1.4-1.8 Ga old) rapakivi granite suite was intruded inBeijing and the area to its east (within Hebei Province), forming three parallel belts of igneous rocks. Theisotopic, trace element and rare earth element geochemical data of a bimodal rock association made up ofanorthosite, gabbro and alkali basalt and olivine-bearing quartz-syenite, rapakivi granite and trachyte as wellas potassic A-type granites and anorogenic granites—— all suggest that there exists an incipient rift in thestudy area. Fractional crystallization of a mixed magma formed by the magma derived from the upper mantleand the magma derived by small degrees of fusion of the lower crust produced anorthosite cumulates. Thewater-deficient granitic magma was differentiated into a subalkaline series. When the fractional crystallizationwas incomplete, rhythmic eruptions took place.

关键词： Geochemistry of a Rapakivi Granite Suite in a Proterozoic Rift Trough in Beijing and Its Vicinity

The Igneous Rock Series and Tin Polymetailic Minerogenetic Series in the Tengchong Area, Yunnan

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 175-187页

作者： Mao Jingwen institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing fei zhenbi

This paper discusses the late Yanshanian-Himalayan igneous rock series and minerogenetic series (Cheng et al., 1979, 1982) related to tin polymetallic deposits in the Tengchong area. The multi-stage differentiation and evolution of the igneous rock series led to the concentration of metal and ore-forming elements in a cupola of a granite body formed in the late stage. The minerogenetic series shows a zoning of Nb-Ta-W-Sn, Sn-Fe and Sn around the cupola in space and a multi-stage regularity in time. Finally a minerogenetic model and three key factors of tin minerogenesis are put forward for tin polymetallic deposits in the area.

关键词： The Igneous Rock Series and Tin Polymetailic Minerogenetic Series in the Tengchong Area Yunnan

New Data of Daomanite and Hongshiite

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 458-465页

作者： YU Zuxiang institute of Geology, Chinese Academy of geological sciences, Beijing 100037 fei zhenbi institute of Geology Chinese Academy of Geological Sciences Beijing 100037 [?]2Yu Zuxiang Born in 1930 graduated from Beijing College of Geology in 1953 now research professor at the institute of Geology CAGS. He has long engaged in the study of platinum minerals and mineral deposits. Tel.: (010)68328449.

In 1974 the author preliminarily reported two new platinum group minerals—daomanite and hongshiite. The two minerals were accepted by the Commission on New Minerals and Minerals Names of the International Mineralogical Association in 1976 and 1982 respectively. Because of the conditions at that time, the work was preliminary, for example, there were only reflectance values of four wave bands. Recently the author again made measurements of reflectances, corrected cell parameters by the four-circle diffractometer and electron diffraction and supplemented their new occurrences and nomenclature.

关键词： daomanite hongshiite new data

Precambrian Geochronology, Chronotectonic Framework and Model of Chronocrustal Structure of the Zhongtiao Mountains

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 23-37页

作者： Sun Dazhong Li Huimin Lin Yuanxian Zhou Huifang Zhao Fengqing Tang Min Tianjin institute of Geology and Mineral Resources, Chinese Academy of geological sciences, Tianjin fei zhenbi Tianjin institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Tianjin

The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained by means of three methods, several aspects are dealt with: (1) the dating results obtained by differentmethods and their geological implications have been compared; (2) a chronotectonic framework has been con-structed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobilebelt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects theages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium modelage of the depleted mantle sources (T_(DM)) and geochemical and geological data, a model of Precambrianchronocrustal structure has been constructed, representing a typical for the North China craton.

关键词： Precambrian Geochronology Chronotectonic Framework and Model of Chronocrustal Structure of the Zhongtiao Mountains

Mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing geological Party No.3, Hebei Bureau of Geology and Mineral Resources, Zhang jiakou, Hebei fei zhenbi institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2Te. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： Mineralogy and Mode of Occurrence of Gold Hebei Province

The Characteristics and Mechanism of Island-Arc Volcanism on the Central and Southern Fildes Peninsula, King George Island, Antarctica

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 39-57页

作者： Li Zhaonai Liu Xiaohan Shang Ruxiang fei zhenbi institute of Geology Chinese Academy of geological Science.institute of Geology,Academia Sinica. 1institute of Geology Chinese Academy of Geological Science. 2institute of Geology Academia Sinica.

The volcanic rock series on the Fildes Peninsula is the product of the later subduction of the Pacific platebeneath the Antarctic plate. It consists mainly of basalt, basaltic andesite and andesite with minor dacite. Itsisotopic ages range from 64.6±1 to 43±2 Ma, belonging to Palaeocene to Eocene. Volcanism in the area maybe divided into two phases. The contents of major oxides, rare earth elements (REE) and trace elements in vol-canic rocks formed in different phases show regular changes, which are mainly related to the rock associationsof these phases. Isotope geochemical studies indicate that the primitive magma in the area originating by par-tial melting in the upper mantle underwent fractional crystallization and ascended to the high-level (shallow)magma chamber. Before eruption the primitive basalt-andesitic magma was subjected to differentiation in thehigh-level magma chamber, forming zones of derivative magmas of different compositions. In various phasesmagma-conducting faults experienced periodic extension and cut through various derivative magma zones indifferent parts of the peninsula, leading to the eruption of magmas of different compositions on the surface andthe formation of volcanic rock associations of corresponding compositions.

关键词： rock Antarctica The Characteristics and Mechanism of Island-Arc Volcanism on the Central and Southern Fildes Peninsula Arc

Permian Alkaline Granites in Central Inner Mongolia and Their Geodynamic Significance

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Acta Geologica Sinica(English Edition) 1995年第1期69卷 27-39页

作者： Hong Dawei, Huang Huaizeng, Lithosphere Research Center, Chinese Academy of geological sciences, BeijingXiao Yijun, institute of Geology, Chinese Academy of geological sciences, BeijingXu Haiming,institute of Mineral Deposits, Chinese Academy of geological sciences, Beijingand Jin M anyuanTianjin geological Academy, Ministry of Metallurgical Industry, Tianjin fei zhenbi Lithosphere Research Center Chinese Academy of Geological Sciences Beijing China

Alkaline granites (Rb-Sr ages 276-286 Ma)occurring in the Bayan Ul-East Ujimqin belt at the southern margin of the Siberian plate originated in a tensional tectonic environment about 60 Ma earlier than the Late Devonian to Early Carboniferous collision between the Siberian and Sino-Korean plates. They belong to post-orogenic A-type granites and may be used as an indicator of the end of the orogeny. At the northern margin of the Sino-Korean plate, however, only late-orogenic calc-alkaline granites occurred during the late Caboniferous-Permian, and alkaline syenites did not appear until the Late Triassic. The asymmetric magmatism at the margins of the two neighbouring plates might be controlled by the differences in size and mass of the two plates.

关键词： alkaline granite geodynamics Inner M ongolla