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1.
东秦岭泥盆纪山阳—柞水成矿区电气石矿物化学和硼同位素组成 总被引：8，自引：0，他引：8
东秦岭泥盆纪山阳－柞水成矿区内众多层控贱金属硫化物矿床含矿层中含有相当比例的电气石，这些电气石属于黑气石－镁电气石类质同象系列，一般Ｍｇ〉Ｆｅ，Ｎａ〉Ｃａ（阳离子比较），明显的成分环带记录了主成矿期的海底（喷气）热液沉积成矿方式和随后的区域变质及热液叠加过程，在主成矿期形成的电气石的化学成分［ＦｅＯ／（ＦｅＯ＋ＭｇＯ）＝－０．３４－０．３９］和硼同位素组成（δ＾１１Ｂ＝－７．６‰￣－８．８‰）与海 相似文献
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新疆白杨河U-Be矿床中电气石的矿物学特征及其成矿指示 总被引：3，自引：2，他引：1
新疆白杨河铀铍矿床是近年发现的亚洲最大的铍矿床,它位于新疆西准噶尔地区雪米斯坦(谢米斯台)火山岩带内。大地构造上处于哈萨克斯坦-准噶尔板块西北缘古生代陆缘活动带内晚古生代成熟岛弧之上。铀铍矿体主要赋存于杨庄花岗斑岩体与上泥盆统塔尔巴哈台组凝灰岩接触带以及花岗斑岩中。野外观察发现白杨河铀铍矿床中电气石以三种不同产状产出:(1)产于玄武岩中电气石;(2)产于凝灰岩中电气石;(3)产于花岗岩中电气石。电气石在玄武岩和凝灰岩中主要以球状集合体为主,部分沿裂隙充填;而在花岗岩中则主要呈针状以浸染状产出。本文在野外详细观察和岩相学基础上,利用电子探针点、面分析技术,对白杨河不同产状的电气石进行了详细的矿物化学研究工作。结果显示,白杨河铀铍矿床中的电气石均属于碱质黑电气石,但不同产状的电气石其化学成分存在明显差异。玄武岩中的富Ti、Mg和Ca,贫Al、Mn和F;凝灰岩中的富Fe和Na,贫Mg和Ca;花岗岩中的富Al、Mn、F,贫Ti、Fe和Na。不同类型的电气石中均具有较高的F(0. 343～1. 117apfu)和Al(5. 648～7. 351apfu)。白杨河U-Be矿床中电气石化学成分的变化是Al~(Y X)□(Y+Na)_(-1)、Al~(Y X)□(Y+OH)-1和FeMg_(-1)、Fe~(3+)Al_(-1)、AlO(MgOH)_(-1)和AlO(Fe3+OH)_(-1)等替代机制联合作用的结果。白杨河铀铍矿床中电气石化学成分表明形成电气石的流体是富Al、富F的流体; Be可能主要以氟化物或者氟络合物、U主要以氟化物或者氟碳酸盐的形式在热液流体中迁移;电气石或萤石的沉淀导致含U和含Be的氟化物或者氟络合物失稳,致使铍、铀富集成矿。 相似文献
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西太平洋冲绳海槽烟囱硫化物矿床矿石化学特征与分带型式 总被引：12，自引：0，他引：12
西太平洋冲绳海槽烟囱式硫化物矿床分布于琉球弧后扩张盆地、产于尹是名洼陷盆地（深１４００ｍ），其特征与日本黑矿类似。硫化物矿石及烟囱主要有３种化学类型：Ｐｂ－Ｚｎ－Ｂａ型、Ｚｎ－Ｐｂ型和Ｃｕ－Ｚｎ型，三者分别代表温度不断升高的热液体系的早、中、晚３个成矿阶段产物，其中，Ｐｂ－Ｚｎ－Ｂａ矿石及烟囱形成于高ｆｏ２环境和高流速、低温、富Ｐｂ、Ｚｎ、Ｂａ热液体系，Ｃｕ－Ｚｎ矿石及烟囱形成于低流速、高温、富Ｃｕ热液体系，Ｚｎ－Ｐｂ矿石则介于其间。硫化物烟囱显示明显的矿物－化学分带。在Ｐｂ－Ｚｎ－Ｂａ矿石（烟囱），Ｚｎ、Ｃｄ集中于烟囱中央，Ｂａ、Ｆｅ、Ａｓ、Ｓｂ、Ａｇ、Ｐｂ集中于烟囱外带，Ｃｕ则富集于烟囱中外部。在Ｃｕ－Ｚｎ矿石，Ａｓ、Ｓｂ、Ｆｅ、Ａｇ、Ａｕ仍富集于烟囱外带，Ｃｕ、Ｚｎ、Ｐｂ则在烟囱中央富集。依此元素化学分带型式，建立了古代黑矿硫化物矿体分带与硫化物堆积模式。 相似文献
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辽东地区硫铁矿床中电气石岩热水沉积剖面结构序列 总被引：17，自引：0，他引：17
电气石岩在辽东元古宙裂谷内的硫铁矿床中广泛发育，辽河群高家峪含矿建造中，富电气石岩主要与硫铁矿体成矿关系密切。这种富电气石岩产出层位稳定，在成因上具有特殊的纹层状、条带状、块状剖面结构序列。这种由纹层状电气石岩逐渐过渡到块状电气石磁黄铁矿石（层）的演变特征，是海底喷流成矿作用的典型代表。经对比研究，辽东地区的电气石岩与世界许多超大型块状硫化物矿床，尤其是沉积岩中的（ＳＥＤＥＸ）矿床中的电气石岩特征十分相似。本文通过电气石岩韵律层的自组织成因，电气石的ＦｅＯ／（ＭｇＯ＋ＦｅＯ）比值、氢氧同位素、稀土元素组成等的研究，建立了热水沉积电气石岩的序列找矿模式。提出了电气石岩是元古代克拉通裂谷环境中海底喷流作用形成的。纹层状电气石岩与块状电气石磁黄铁矿石（层）的这种成因联系具有重要找矿标志意义。它的出现可以指示热液通道，喷口的位置及热水沉积盆地的范围。从而为确立矿体的分布规律提供信息。依据这一成矿标志，在面临闭坑的老矿山外围找到了矿体 相似文献
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老厂花岗岩破碎带型锡矿床地质地球化学特征 总被引：9，自引：1，他引：8
新矿床类型—花岗岩内破碎带型锡矿床受五子山复式背斜轴部附近的花岗岩突起中盆状构造及ＥＷ向断裂控制;矿体定位于岩盆陡缓交接处与压扭性断裂的组合部位,呈等轴囊状,严格受构造破碎带控制。矿石具有明显的挤压破碎特征;矿石矿物组合为黄铁矿、毒砂、锡石、菱铁矿等,脉石矿物中有相当部分为继承花岗岩中的矿物。围岩蚀变为绢云母化、黄铁矿化、碳酸盐化。稀土元素、稳定同位素等特征均表明：成矿物质主要来源于花岗岩;成矿流体为高ＣＯ２的富Ｋ＋、Ｃａ２＋、Ｍｇ２＋、ＳＯ２－４、Ｆ－等,贫Ｎａ＋、Ｃｌ－的气液流体。在正接触带锡石硫化物矿床形成的稍晚阶段,成矿热液受其上厚层矽卡岩矿体的遮挡而被圈闭于花岗岩内破碎带充填交代的产物。 相似文献
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可可塔勒铅锌矿床为泥盆系海相火山岩系中沉积岩容矿的块状硫化物矿床，位于阿尔泰山南缘多金属成矿带的麦兹地区。该火山岩系以Ｋ２Ｏ〉Ｎａ２Ｏ为特征。含矿岩系下部多数岩石中Ｐｂ、Ｚｎ等元素的含量明显偏低，容矿岩石ＣａＯ、ＴＦｅ、ＭｇＯ及Ｍｎ的含量较高，且富含Ｐｂ、Ｚｎ等元素。矿体位于Ｎａ２Ｏ、Ａｌ２Ｏ３的亏损带及ＣａＯ、ＴＦｅ、ＭｇＯ和Ｍｎ的高含量区范围内。 相似文献
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电气石岩是一种富硼的硅质喷气岩,主要产于以沉积岩为容矿岩石的喷气矿床中及附近。研究广泛认为其与喷流-沉积型块状硫化物矿床(SEDEX矿床)有着密切的关系,并被视为该类矿床找矿勘探的标志岩性之一。综述了电气石岩的产出环境、形态、岩石学、地球化学等地质特征,分析了电气石岩的沉积环境及成因。以澳大利亚布罗肯希尔地区电气石岩与矿化的关系为例,对其地质找矿意义进行了总结与展望。 相似文献
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哀牢山—金沙江裂谷系岩石中镁铁云母成分特征及其岩石学意义 总被引：6，自引：5，他引：6
本区的Ｍｇ－Ｆｅ云母是富镁黑云母及金云母，ＭＦ＞１．３５，属于富镁、富碱、高硅、贫铁类型云母。根据Ｍｇ－Ｆｅ云母的成分及形成的物化条件，表明其寄主岩石属于富碱，浅成一超浅成的幔源岩石。 相似文献
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引言本文主要评述元古宙与火山岩伴生的喷气块状硫化物矿床类型及其地质环境。层控喷气块状硫化物矿床在全世界元古宙地体中都有分布。这些矿床是铜、锌、铅、银、金、镉和锡的重要来源。有几个元古宙含镍块状硫化物矿床可能是属于这种矿床类型。用来说明这种矿床类型的例子有北美、澳大利亚、南非、斯堪的纳维亚和芬兰的矿床。但这种类型的矿床已知在某些其它元古宙地体中也有分布,例如苏联和印度的矿床。元古宙喷气块状硫化物矿床的金属比例是从富铜和贫铅及锌变到富铅及锌和贫铜。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
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正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
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正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
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正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
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正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
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正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献
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正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献