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The Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County, Yunnan province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 271-287页

作者： Zhao Daxian Tang Guangting The Fifth geological Party, Yunnan bureau of Geology and Mineral Resources, Simao,Yunnan Liu Linqun The Fifth geological Party Yunnan Bureau of Geology and Mineral Resources Sirnao Yunnan

Through studies on the element geochemistry, alteration of country rocks, ore-forming fluids and isotopegeochemistry of the Arno tin deposit in the metamorphic rocks of the Upper Proterozoic Ximeng group, theauthors consider that the concentration of the B-F-Li-Rb-Cs-Sn association is related to acidic magmatism inthe study area. The Fe-Mg-Li tourmaline in the ore is the replaced product of the country rocks byhypothermal fluid. The δ^(18)O values of mineral separates are +2.01- +13.16‰ and their δ^(34)S values, +2.6-+7.2.. The ore-forming materials were derived from hydrothermal fluid of granitic magma. For themineralization, the temperature is 450°-350℃, the pressure, 450-1000×10~5 Pa, and the age, Himalayan(2..5 Ma). According to the geochemical characteristics, a minerogenic model is established: the deposit is ahypothermal cassiterite-quartz vein type tin deposit controlled by the hidden Himalayan granites.

关键词： The Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County Yunnan province

Tectonic Framework and Evolution of the Dabie Mountains in Anhui, Eastern China

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 221-238,326页

作者： Xu Shutong Jiang Laili Liu Yican Zhang Yong Institute of geological Sciences of Anhui province, Hefei, Anhui Sun Sheping Institute of geological Sciences of Anhui province Hefei Anhui

The Dabie Mountains are believed to be a collisional orogenic belt between the Yangtze amd Sino-Koreancontinental plates. It is composed of the foreland fold-thrust zone, the subducting cover and basement of theYangtze continental plate, the coesite- and diamond-bearing ultra-high pressure metamorphic zone and themeta-ophiolitic melange zone in the subducting basement, the fore-arc flysch nappe and the back thrust zoneoccurring respectively on the southern and northern margins of the Sino-Korean continental plate and the in-herited basin with molassic deposits on the northern margin. When the palaeo-Dabie oceanic plate subductednorthward in the Early Palaeozoic, volcanic arc and back arc basin probably formed on the southern margin ofthe Sino-Korean continental plate. The Sm / Nd isotopic dating of the strata and eclogite which were drawn in-to the foreland fold-thrust zone indicates that the intense collision of the two continental plates took place inthe Early Mesozoic.

关键词： collisional orogenic belt ultra-high pressure metamorphic zone ophiolitic melange zone coesite diamond

湖北大冶的早侏罗世祁阳蚌(Qiyangia)动物群

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古生物学报 1986年第4期 454-462页

作者：徐家荣湖北省地质局区域地质测量队

1965年,湖北省区测队在大冶地区进行区测工作时,曾于大冶县金山店地区的中生代含煤地层武昌群中采获一批双壳类化石。最近经笔者重新鉴定,这批双壳类属于我国华南广泛分布的早侏罗世祁阳蚌(Qiyangia)动物群,该动物群在鄂东南为首次发现... 详细信息

1965年,湖北省区测队在大冶地区进行区测工作时,曾于大冶县金山店地区的中生代含煤地层武昌群中采获一批双壳类化石。最近经笔者重新鉴定,这批双壳类属于我国华南广泛分布的早侏罗世祁阳蚌(Qiyangia)动物群,该动物群在鄂东南为首次发现,对于以往长期争议的武昌群的划分对比及时代确定具有重要意义。成文过程中承南京地质古生物研究所陈金华和我队陈公信的帮助和支持。图版由李兴尧、

关键词：早侏罗世侏罗纪图版 Qiyangia 植物化石动物群动物区系登记号茅仙岭组雾中山须家河组广元煤系煤组金华浙江双壳类动物香溪组祁阳湖北大冶

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甘肃的志留系

甘肃地质 1985年 1-116页

作者： regional geological Surveying {2., geological Burean of Gansu province 甘肃省地质局区域地质调查队

甘肃的志留系发育良好,三统具全,剖面连续,化石丰富,是我国志留系研究的良好地区之一。前人虽然对志留系做了大量工作,但目前依然存在着许多问题,有待进一步查清。本文采用的资料主要为区调成果,并利用了其它有关资料。

关键词：志留系西秦岭灰岩笔石层中志留统笔石化石粉砂岩互层志留纪哥特兰纪甘肃

REE Geochemistry and Mineralization Characteristics of the Zudong and Gnanxi Granites, Jiangxi province

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 139-157页

作者： Huang Dianhao, Wu Chengyu Institute of Mineral Deposits, Chinese Academy of geological Sciences, Beijing and Han Jiuzhu Southern Jiangxi geological Survey Party, Jiangxi {2. of Geology and Mineral Resources, Ganzhou Zhang Zhong min Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

The Zudong and Guanxi granites are original rocks of the ion adsorption-type HREE and LREE deposits in weathering crust of granites. The ΣREE value and LREE/HREE ratio of the Zudong granite are 2.4 ppm and 0.81-0.2. respectively, and the average Y/ΣREE ratio is 35.8-54.5%. This is mainly due to magmatic crystallization and evolution and deuteric metasomatism (albitization, muscovitization and fluorite-doveritization). These alterations resulted in endogenic mineralizations of yttrium-group REE fluorine carbonates, silicates and arsenates. The Guanxi granite is characterized by LREE enrichment (the average LREE/HREE ratio is 2.43).

关键词： REE Geochemistry and Mineralization Characteristics of the Zudong and Gnanxi Granites Jiangxi province

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福建沿海中生代变质带的基本特征

福建地质 1982年第2期 29-52页

作者： regional geological Survey {2. of Fujian province 福建省区测队变质岩组

福建沿海中生代变质带,其范围,北起马祖,经平潭、晋江、东山,南至广东南澳岛,长达400公里,宽38～58公里。变质带主要由中生代地层组成。变质岩、混合岩和花岗质岩石广泛发育,为一典型的低压型(红柱石——矽线石型)区域变质带。这一变质... 详细信息

福建沿海中生代变质带,其范围,北起马祖,经平潭、晋江、东山,南至广东南澳岛,长达400公里,宽38～58公里。变质带主要由中生代地层组成。变质岩、混合岩和花岗质岩石广泛发育,为一典型的低压型(红柱石——矽线石型)区域变质带。这一变质带的查明,对我国东南沿海板块构造的认识,具有重要意义。

关键词：变质带福建沿海混合岩化变质作用地质作用中生代地层变质地层岩石化学火山沉积岩钾长石碱性长石原岩建造变质岩花岗质岩石黑云母斜长石低角闪岩相福建

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西秦岭南坡的志留系

甘肃地质 1986年 33-62页

作者： regional geological Surveying {2. of Gansu province 甘肃省地质矿产局区调队

本文为1980-1982.我们进行“西秦岭志留纪地层划分与对比”研究工作的成果,1983年由甘肃省地质矿产局进行审查验收。现整理成文,以供参考。鉴于研究区仅限于甘肃南部白龙江两岸的原“白龙江群”分布区和武都-宝成铁路一带的原“白水... 详细信息

本文为1980-1982.我们进行“西秦岭志留纪地层划分与对比”研究工作的成果,1983年由甘肃省地质矿产局进行审查验收。现整理成文,以供参考。鉴于研究区仅限于甘肃南部白龙江两岸的原“白龙江群”分布区和武都-宝成铁路一带的原“白水江群”分布区,故称西秦岭南坡的志留系。该区志留系早在1944年为关士聪、叶连俊创名报导。解放后研究工作者颇多。但真正的深入研究是1967年以后。这一时期由于区调工作的开展,以及一些科研单位特别是西安地质矿产研究所的反复研究,才使这一地区的志留系研究程度显著提高。(表1,2.

关键词：志留系薄层粉砂岩地层碎屑岩板岩变质岩灰岩秦岭南坡

AN IMPORTANT DEVONIAN-CARBONIFEROUS BOUNDARY STRATOTYPE IN NERITIC FACIES OF YISHAN COUNTY, GUANGXI

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微体古生物学报 1985年第1期 40-46页

作者： Wang Cheng-yuan (Nanjing Institute of Geology and Palaeontology, Academia Sinica) Yin Bao-an (regional geological Surveying.{2., Guangxi province)

In 1979,the IUGS Working group on the Devonian-Carboniferous boundary made an outstanding resolution that the Devonian-Carboniferous boundary should be chosen at the first appearance of the conodont Siphonodella sulcata within the evolutionary lineage from S. praesulcata to S. sulcata. Since then, the Working group have visited several sections in different countries and discussed the attributes and detractions of each section. After thorough discussion and deliberation, the Working group recommended four sections as condidates for the international Devonian-Carboniferous boundary stratotype, namely Hasselbachtal, Kija, Berchogur and Muhua, of these four the Muhua section has been ranked as the leading contender of the candidates.

关键词： Carboniferous sections evolutionary appearance margin thorough strata discussion visited Upper

SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha group in Tibet

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Science China Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2. YE Peisheng1 & LIU Qisheng1 1. Institute of Geomechanics, Chinese Academy of geological Sciences, Beijing 100081, China 2. Institute of Geology, Chinese Academy of geological Sciences, Beijing SHRIMP Centre, Beijing 100037, China 1. Institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 2. Institute of Geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre 100037 Beijing China

The Nyainqêntanglha group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 2.7Pb/2.6Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha group, SHRIMP dating, Nd isotope, Neoproterozoic, Tibet.