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广东河台金矿构造应力场演化及构造控矿模式 总被引:3,自引:1,他引:2
广东河台金矿位于两广云开大山地区吴川-四会断裂变质带与广宁-罗定断裂变质带交汇部位,为一典型的韧性剪切带蚀变糜棱岩型金矿。海西-印支期区域SN向左旋挤压应力形成有区域左行韧性剪切性质的吴川-四会断裂变质带和广宁-罗定断裂变质带;燕山早期,区域构造应力转为SN向右旋挤压,区域韧性剪切带转为右行韧性剪切性质,并对先期形成的糜棱岩带改造显示为右行剪切特征;燕山晚期,大规模的右行韧性剪切活动逐渐转为右行脆-韧性、脆性剪切,在部分糜棱岩带中产生脆性断裂。河台金矿严格受韧性剪切糜棱岩带控制。区域吴川-四会断裂变质带和广宁-罗定断裂变质带是一级构造,两者交汇部位控制了河台金矿田的产出;燕山期,广宁-罗定断裂变质带的C-R次级构造(即河台韧性剪切带及其糜棱岩带)是二级构造,控制了河台金矿床的分布;河台矿区糜棱岩带中的张剪裂隙和主剪切裂隙系统是第三级构造裂隙,控制了河台金矿床的类型(蚀变糜棱岩型和石英脉型)及金矿体的分布和形态。 相似文献
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根据华北陆台北缘金矿的赋存部位和富集特点,划分出9种金矿类型。金矿的形成主要受韧性剪切带控制,多形成于韧脆性剪切带的上部;金的迁移和富集经历3个阶段:(1)地体表壳岩矿源层形成阶段;(2)地体拼贴期韧性剪切带形成阶段;(3)中生代、部分古生代岩浆-构造带形成阶段。控制金矿分布的是古生代近EW向和燕山期NE向构造带,主要为继承早期地体拼贴边界的长寿断裂。金矿集中区位于长寿断裂的交汇部位。 相似文献
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对区内5个成矿带进行研究,提出云开隆起脆性剪切带列控制着金矿化分布的态势;印支期重熔花岗岩和燕山晚期花岗岩迭加的脆性或脆韧性剪切带是金矿床集中部位;金矿成矿斑岩体的定性判别标志,新发现加里东晚期斑岩型矿床;岩浆热液矿床沿构造岩浆岩`带隆起与坳陷交接部位、坳陷里的构造凸起边缘或隆起里的册陷周缓和NNE-NE与NW-NWW走向的壳层逆掩断裂交织的菱形块上升部位或各自的相对上升盘分布,岩浆侵入体出现在构造复合部位,特别是NE向深断裂和EW向、NW向构造复合部位;含矿层位为前这牙纪-二叠纪地层;查明燕山运动期间三次铜、铅、锌(银)区域成岩成矿岩浆活动。 相似文献
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铁岭-靖宇成矿带西段金成矿规律及找矿预测 总被引:1,自引:0,他引:1
铁岭—靖宇成矿带西段构造.岩浆活动具有多旋回特点。太古宙花岗.绿岩带是主要矿源层。通过对典型金矿床成矿特征的分析,区内主要发生2次金矿化,并形成2种主要类型的金矿床,即太古宙末—元古宙早期形成的受韧性剪切带控制的变质层控型金矿床和形成于燕山运动末期、受燕山晚期中酸性岩浆岩控制的岩浆热液型金矿床。主要的控矿部位是区域深大断裂交汇区,特别是叠加NW向断裂并发育燕山晚期中酸性侵入岩体的地段可构成金矿集中区。在上述研究的基础上进行了找矿预测。 相似文献
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辽宁丹东五龙金矿矿化类型及其构造控制机理 总被引:7,自引:1,他引:7
位于辽宁丹东地区的五龙金矿受NE向剪切系统控制.在剪切带发展演化过程中,于不同阶段形成不同类型的金矿化。在早期韧性剪切带上升剥蚀阶段出现的NE向脆-韧性线状剪切带,控制同剪切带型金矿;叠加在韧性剪切带之上的NNE向一级断裂控制破碎带蚀变岩型金矿的形成和分布;沿SN向和NW向的二级断裂构造控制含金石英脉型金矿。 相似文献
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白石嶂钼矿区归属于环太平洋钼成矿带华南褶皱系钨-铜-钼成矿省,成矿于中生代燕山期.矿床赋存于燕山二期细粒二云母花岗岩株南东端西侧与上三叠-下侏罗统地层的接触带,白石嶂断裂(F19)与杨塘断裂的交汇部位.本文从区域地质背景入手,着重研究了地层、构造、岩浆岩与成矿的关系;并对矿床的成矿专属性作了初步探讨.文章对围岩及其蚀变... 相似文献
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内蒙古东部喀喇沁旗地区金矿围岩蚀变遥感信息提取及成矿预测 总被引:6,自引:1,他引:6
内蒙古东部喀喇沁旗地区位于燕山造山带东段的成矿带之上,金矿资源丰富.本文运用遥感技术,结合野外调查,对这一地区金矿围岩矿化异常信息进行了提取和分析.研究表明,本区现有矿床分布与明显受区域构造控制,区内金矿床围岩蚀变以硅化和含铁矿物为主,粘土矿物蚀变较少.区内主要发育3个成矿带,即南北各存在一个近E-W向的成矿带,喀喇沁旗东南发育一个NE-SW向的成矿带,且明显受断裂控制.成矿有利区主要位于本区东南部,且在本区南部NE-SW向断裂和近EW向断裂交汇地带围岩蚀变信息较强,可能为富矿部位.研究表明围岩蚀变遥感异 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