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巴尔哲超大型稀土铌铍锆矿床地球化学和成因 总被引：43，自引：2，他引：43
巴尔哲超大型稀土铌铍锆矿床位于内蒙古自治区扎特鲁旗。矿体赋存在钠闪石花岗岩中，成矿元素主要赋存在兴安石、铌铁矿、烧绍石和锆石中。钠闪石花岗岩侵入在大兴安岭侏罗世火山岩盆地中，矿区位于大兴安岭主脊－林西断裂带与嫩江－八里罕断裂带之间的霍林河东西向断裂带和大兴安岭－太行山－武陵山重力梯度带上。钠闪石花岗岩的Ｒｂ－Ｓｒ等时线年龄为１２５Ｍａ。矿体遭受强烈交代作用，主要为钠闪石化和硅化。巴尔哲钠闪石花岗岩 相似文献
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太白维山大型银矿床地质地球化学特征 总被引：1，自引：0，他引：1
太白维山大型银矿床为典型的中低温火山－次火山隐爆角砾岩型矿床，受岩性和断裂构造控制明显，矿体的产出部位和矿石品级与隐爆角砾岩关系密切。本文通过对基岩和１：２０万水系沉积物资料的分析与处理，得出基岩中主成矿元素组合为Ａｇ－Ｃｕ－Ｐｂ－Ａｓ－Ｓｂ－Ｚｎ，水系沉积物中主成矿元素组合为Ａｇ－Ｐｂ－Ｚｎ－Ｃｄ－Ｍｎ－Ｈｇ的结论，同时指出Ｐｂ可作为此矿床最重要的间接指示元素，而主成矿元素中各单元素异常浓集中心对银矿床的产出部位有很好的指示作用，为找矿的重要指标。 相似文献
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隐爆角砾岩型金矿研究述评 总被引：22，自引：1，他引：22
隐爆角砾岩型金矿是国内外一种具有重要经济价值的矿床类型。不同类型隐爆角砾岩是该类金矿最主要的容矿围岩。造成隐爆作用发生最直接的因素是受热的多源流体或气体，岩浆隐蔽爆破主要作用方式是气爆和浆爆，其次是热液注入。通常气爆发生于早期，浆爆较晚，而热液注入最晚。浅成－超浅成中酸性斑岩体是隐爆角砾岩形成的决定性因素，气液的隐蔽爆破作用是隐爆角砾岩有角砾岩型金－多金属矿床形成的原因，成岩与成矿是同一地质过程不同阶段产物。不同级别的构造对该类型金矿档的产出空间、矿化类型和矿体形态等具有分级控制作用，矿化、蚀变存在明显的垂向分带及其空间套叠。该类型金矿可划分为Au-Ag和Au-Cu系列，矿床系列、矿床规模有富矿部位可通过一系列指标进行判别。 相似文献
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文章阐述隐爆角砾岩型金矿床的定义、成矿构造背景、隐爆角砾岩及其矿床特征、成矿流体特征以及隐爆角砾岩成岩-成矿模式等方面研究进展。隐爆角砾岩型金矿床多产于古老地块活化区、中生代断陷盆地边缘、滨太平洋岛弧火山岩带内。矿体与浅成-超浅成中-酸性斑岩具有密切的时空关系,多赋存于斑岩体的顶部。侵入岩具有富碱、富硅特征,属Ⅰ型花岗岩类。当侵入体顶部高热能流体压力大于围岩抗拉强度和最小主应力之和时发生隐爆作用而形成隐爆角砾岩。隐爆角砾岩筒垂向可分为裂隙相、震碎相、爆破相和通道相;角砾粒径从中心到边缘水平分带一般呈由小到大的趋势。成矿流体由于爆发作用瞬间由封闭体系进入半开放或开放体系,产生较大的压力梯度,流体减压沸腾、混合、不混溶和水岩反应等引起成矿元素稳定的物理化学条件变化,导致金络合物的溶解度降低而产生金矿化。隐爆角砾岩筒的形成及流体演化分别具有"自下而上-顺次推进-序次叠加"和"升温-(爆破)沸腾-降温-升温-(爆破)沸腾-降温"的演化过程,其中"沸腾-降温"阶段为矿质主要沉淀阶段。隐爆角砾岩型金矿的成矿具有"一体多型""一筒多型"的特点,运用矿床系列-成矿系统理论指导勘探找矿具有十分重要的意义。 相似文献
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胶东东部文登金矿床地质特征 总被引：1，自引：0，他引：1
文登金矿是受脆性剪切带控制的构造角砾岩 碎裂岩型金矿床 ,是脆性剪切作用形成的 ,为典型的动力成岩成矿。矿石类型主要是含金碎裂岩 ,含金构造角砾岩 ,网状含金构造角砾岩 ,碎裂化、矿化粗中粒二长花岗岩 4种。成矿作用分为 2期 5个阶段 ,第一期碎裂构造作用———热液期 (内生期 )是主成矿期 ,分 4个成矿阶段。成矿物质来源于原岩 ,主要是昆嵛山超单元中晚期粗粒花岗岩。成矿时代可能为燕山晚期 [成矿期绢云母K Ar年龄为 (10 1 97± 2 4 9)Ma] 相似文献
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在大湖塘北区钨矿找矿勘查过程中,在总结分析20世纪80年代初针对石英大脉型黑钨矿的普查资料基础上,通过地表填图和老窿编录,发现前人认为的混合黑云母花岗岩与混合白云母花岗岩之间为截然清楚的侵入接触关系,二者之间稳定地分布着一层似伟晶岩壳;由空间关系和区域成矿规律推断似斑状黑云母花岗岩为燕山期侵入于晋宁期黑云母花岗闪长岩之中的成矿母岩。晋宁期黑云母花岗闪长岩为成矿有利围岩,在云英岩化等蚀变过程中释放出形成白钨矿的钙离子。燕山期似斑状黑云母花岗岩岩株与晋宁期黑云母花岗闪长岩岩基之间的侵入接触界面是最主要的成矿构造与成矿结构面,控制了主矿体的位置、形态与产状。在研究区内首次于新元古代花岗闪长岩中发现厚大的白钨矿工业矿体,并根据不同岩块混杂、被长英质充填物胶结等特征识别出热液隐爆角砾岩型矿体。基于对矿区成矿地质条件和矿床地质特征的新认识,修改了针对石英大脉型黑钨矿所做的详查设计,抓住细脉浸染型白钨矿这一主要矿床类型,及时调整了找矿目标和勘查手段,在短时间内实现了赣北地区钨多金属找矿的重大突破。通过与石门寺矿段成矿地质条件类比,预测毗邻的苗尾矿段与太平洞矿区找矿潜力大。 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