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Devonian Bivalve Faunas, Life-habits, and Biodiversity Changes in Guangxi, South China

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 378-379页

作者： YAO Huazhou ZHANG Renjie TU Bing YAN Daoping TANG Zhaoyang Wuhan institute of geology and mineral resources China Geological Survey

Objective The Devonian bivalves are well developed, highly diversified and widely distributed in Guangxi. However, they have not been well studied previously, although several papers have dealt with it. Meanwhile, the biodiversity change of bivalves which is one of the most important benthos during Devonian in South China has not been studied yet. The aim of present project is focused on the study of systematic palaeontology, the life-habits, of Devonian bivalves of Guangxi.

关键词： Devonian Bivalve Faunas Life-habits and Biodiversity Changes in Guangxi South China

Sm-Nd,Pb-Pb and Rb-Sr Isotopic Dating and Its Dynamic Implications for the Proterozoic Augen Granite in the Yunkai Area,Western Guangdong Province

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 289-296页

作者： PENG Songbai ZHANG Yeming ZHAN Mingguo CHEN Fuwen QIU Ruizhao Yichang institute of geology and mineral resources CAGSYichang 443003Hubei

The samples of ductile-rheologic deformational augen granite from the Yunkai uplift area, western Guangdong province, were determined by the whole-rock Sm-Nd, Pb-Pb and Rb-Sr isotopic dating to have an Sm-Nd isochron age of 1414±68 Ma, a Pb-Pb isochron age of 1388±90 Ma and a Rb-Sr isochron age of 490±36 Ma. The first two ages are interpreted as the formation age of this suite of granite and the last age represents the timing of the tectono-thermal event of Caledonian ductile-rheologic shear partial melting. It is indicated that in the study area not only an orogeny took place in the Caledonian, but also a more important tectono-magmatic activity occurred in the Meso-proterozoic there, which may be related to the subduction-collision between the Yangtze block and Cathaysia block.

关键词： Yunkai area Proterozoic augen granite isotopic dating ductile-rheologic shear

Continental- Margin Structure of Northeast China and Its Adjacent Areas

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 241-258页

作者： Tang Kedong, Shenyang institute of geology and mineral resources, Shenyang,Liaoning ProvinceWang Ying,Bureau of geology and mineral resources of Heilongjiang Province,Harbin, HeilingjiangHe Guoqi and Shao Ji’an Peking U niversity, Beijing Liu Xinzhu Shenyang institute of geology and mineral resources Shenyang China

The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench *** existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate.

关键词： continental-margin structure Bohai Sea block Mesozoic terrane non- subducted ocean crust Palaeo - Pacific Ocean

Metallogenic Features and Metalogenic Model of Laterite Gold Deposits in Southern China

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 565-569页

作者： CHEN Dajing YANG Mingshou Guilin Research institute of geology of mineral resources Guilin 541004

The modern laterite gold deposits in southern China, which belong to reworked laterite deposits, can be further divided into three subclasses and seven types. Their geological features, ore-forming conditions and regu... 详细信息

关键词： laterite gold deposit geological feature ore-forming condition metallogenic model southern China

Qinling Orogenic Belt:Its Palaeozoic-Mesozoic Evolution and Metallogenesis

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 452-457页

作者： SHAO Shicai Beijing institute of geology for mineral resources BeiyuanAndingmenwaiBeijing 100012

The formation, development and evolution of the Qinling orogenic belt can be divided into three stages: (1) formation and development of Precambrian basement in the Late Archaean-Palaeoproterozoic (3.0–1.6 Ga), (2) p... 详细信息

关键词： Qinling orogenic belt evolution metallogenesis

U-Pb zircon ages of intermediate granulites and deformed granites in Dabie Mountains, Central China

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Chinese Science Bulletin 1996年第22期41卷 1886-1890页

作者：陈能松游振东索书田杨勇李惠民 Faculty of Geological Sciences China University of Geosciences Wuhan 430074 China Tianjin institute of geology and mineral resources. Ministry of geology and mineral resources Tianjin 300170 China

In the Dabie area,the coesite- and microdiamond-bearing eclogites are wellexposed,and metamorphic rocks of granulite and amphibolite facies are much *** recent years a number of methods are systematically applied to thedating of eclogite ***,the age of granulitic rocks are scarcely *** obtained results of U-Pb dating of minor amount zircon single crystals extractedfrom the intermediate granulites and the deformed granites are reported.1 Geological aspects of

关键词： granulite facies of metamorphism deformed granite U-Pb zircon geochronology Dabie Mountains.

Magnetic properties and their paleoclimatic implications revealed from the last glacial eolian sedimentary sequence in Pengze,Jiangxi

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Science China Earth Sciences 2002年第8期45卷 691-701页

作者：刘健李绍全朱日祥葛宗诗 institute of geology and Geophysics Chinese Academy of Sciences Beijing China institute of Marine geology Ministry of Land and Mineral Resources Qingdao China

The sand-hill section in Hongguang, Pengze County, Jiangxi Province is composed of eolian sand beds interbedded with 12 weakly-pedogenetic paleosols, and this sedimentary sequence was formed from about 25 to 13 kaBP. A detailed rock-magnetic study demonstrates that the magnetic minerals in the sequence are dominated by multi-domain magnetite grains in addition to small amounts of maghemite and hematite. Compared with the eolian sand beds, the paleosols are characterized by smaller magnetic particles, higher proportion of low-coercivity minerals and markedly increase in the magnetic mineral content. In the section, various magnetic parameters (K, ARM, SIRM and S ratios) display a roughly gradual increase from eolian sand beds to the overlying paleosols but an abrupt decrease from paleosols to the overlying eolian sand beds. The content of low-coercivity magnetic minerals shows the lowest values in the second eolian sand bed from the bottom of the section, and from the bed upwards it gradually increases on the whole in the eolian sand beds. These magnetic properties reflect regional climatic changes during the last glacial maximum.

关键词： eolian deposits environmental magnetism last glaciation paleoclimate Jiangxi.

Hydrogen and Oxygen isotope Fractionation Mechanism in the Hydrothermal System and Its Geologic Significance

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Acta Geologica Sinica(English Edition) 1992年第4期66卷 397-409页

作者： Chen Zhensheng Zhang Ligang Yichang institute of geology and mineral resources, Chinese Academy of Geological Sciences, Yichang, Hubei Jiang Minxi Yichang institute of geology and mineral resources Chinese Academy of Geological Sciences Yichang Hubei

The geochemical behaviors of hydrogen and oxygen isotopes in the hydrothermal system and their inher-ent relationship with the water / rock exchange are discussed in this paper In addition to the temperature con-ditions, the effective W / R ratio is another factor controlling the changes in H and O isotope compositions ofthe altered rock and hydrothermal water. Besides, the application and geological significance of the water-rockexchange theory are also discussed in the light of the H and O isotope compositions and their variation charac-teristics of the mineralizing hydrothermal water and altered rocks from several mineral deposits. Finally, abrief evolutional model of H and O istotope compositions of meteoric and magmatic hydrothermal waters in ahydrothermal system is given.

关键词： hydrothermal system isotope fractionation mechanism water/rock exchnage effective W/R ratio evolutional model

Rare Earth Element Behaviour in theWunugetushan Copper - Molybdenum Deposit,Inner Mongolia, and Its Implications

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 153-167页

作者： Qin Kezhang and Wang ZhitianBeijing institute of geology for M ineral resources, CNNC, Beijing Beijing institute of geology for mineral resources CNNC Beijing

Considering porphyry and wall rocks as a whole system, the behaviour of rare earth elements (REE) in hydrothermal alteration and mineralization of the exceedingly large Wunugetushan porphyry Cu-Mo deposit of Inner Mongolia has been studied. It has been found for the first time that there exists complementary REE variation in hydrothermal alteration between porphyry and wall rocks, and Eu depletion has certain significance in indicating mineralization. Based on an analysis of the variation in REE contents of relevant minerals during the hydrothermal alteration, the ore-forming fluids are inferred to be depleted in ∑REE, comparatively enriched in ∑Y and strongly depleted in Eu. In the intermediate-strong alteration zones, porphyry and wall rock took part in hydrothermal metasomatism and alteration almost in equal ratio mass. Furthermore, studies of REE and hydrogen and oxygen isotopes and fluid inclusions confirm the existence of hydrothermal convection and the possibility of supplying part of ore materials by the wall rock and indicate that the application of REE geochemistry in mineral prospecting is promising.

关键词： REE complementary nature Eu depletion hydrothermal convection Wunugetushan Cu-Mo deposit Inner Mongolia