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1.
晋南中条山北峪奥长花岗岩的岩石地球化学 总被引：3，自引：0，他引：3
野外工作发现，北峪奥长花岗岩侵入于绛县群变富钾流纹岩之中，结合其２１０７±５９Ｍａ的全岩Ｒｂ－Ｓｒ等时线年龄，应为早元古代岩浆侵入的产物。北峪岩体具高的Ａｌ２Ｏ３含量和高的δ＾１８ＯＳＭＯＷ（‰）比值，表明为铝过饱和的Ｓ型花岗岩。其高的Ａｌ２Ｏ３含量和低的Ｙｂ含量及强烈分异的稀土图谱，表明形成于大陆环境。在ＬＩＬＥ元素特点上，北峪奥长花岗岩亏损Ｕ，Ｔｈ，Ｋ，Ｒｂ，具低的Ｒｂ／Ｓｒ比值和高的Ｋ／Ｒｂ 相似文献
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赣南寨背A型花岗岩体的地球化学特征及其构造地质意义 总被引：86，自引：9，他引：77
赣南寨背岩体主要为黑云母钾长花岗岩,黑云母结晶晚于长石和石英,锆石群型地温测量标尺显示其结晶温度为８００℃～９００℃,表明寨背岩体形成于一种高温贫水的花岗质岩浆。岩石的化学成分特点为准铝质（Ａｌ２Ｏ３为１２．２１％～１２．６２％）,富硅（ＳｉＯ２为７５．６６％～７６．７４％）,偏碱（Ｎａ２Ｏ＋Ｋ２Ｏ为７．９３％～８．９０％）,ＦｅＯＴ／ＭｇＯ值高（５９～１４８）,ＣａＯ和ＭｇＯ含量低（分别为０．１０％～０．６５％和０．０１％～０．０２％）,富含ＲＥＥ（Ｅｕ除外,ΣＲＥＥ平均为５００μｇ／ｇ）,Ｙ、Ｇａ、Ｎｂ等高场强元素（ＨＦＳＥ）以及Ｆ,Ｓｒ和Ｂａ较低。这些特点与本区的Ｉ型和Ｓ型花岗岩有明显差别,是一种典型的Ａ２型花岗岩。寨背岩体Ｒｂ－Ｓｒ等时线年龄为１７６Ｍａ,与辉长岩、双峰式火山岩有密切的时空关系,表明赣南地区在燕山早期即进入拉张裂解阶段。 相似文献
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一个古元古代A型流纹岩 总被引：17，自引：2，他引：15
山西吕梁群流纹岩是一个古元古代的弱碱性火山岩,它具有高ＳｉＯ２,Ｎａ２Ｏ＋Ｋ２Ｏ和Ｚｒ,Ｇａ等高场强元素和高ＦｅＯ＾＊／ＭｇＯ,Ｒｂ／Ｓｒ和Ｇａ／Ａｌ比值,以及低ＣａＯ,Ｓｒ和Ｅｕ／Ｅｕ＾＊的地球化学特征,相似于Ａ型花岗质岩石。它形成于大陆边缘裂谷环境,化学成分及同位素特征为高εＮｄ（ｔ）值,低（＾８７Ｓｒ／＾８６Ｓｒ）ｉ值,表明流纹岩的原始岩浆由下地壳晚太古代变质岩受裂谷岩浆和热流作用的影响部分 相似文献
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小秦岭303号石英脉流体包裹体Rb—Sr,^40Ar—^39Ar成矿年龄测定 总被引：10，自引：2，他引：8
用石英流体包裹体Ｒｂ－Ｓｒ、＾４０Ａｒ－＾３９Ａｒ法测定了小秦岭３０３号石英脉的形成时代为石元古代。其流体包裹体属Ｈ２Ｏ＋ＣＯ２＋ＣａＣｌ型,盐度为６．５％－１２．９８％,ＣＯ２含量高,Ｎａ＾＋〉Ｋ＋。３０３号石英脉Ｒｂ－Ｓｒ等时线年龄为（２３８２±３３６）Ｍａ－（２２３４±４７）Ｍａ,（＾８７ｓＲ／＾８６Ｓｒ）ｉ为（０．７３５１±０．００１９）－（０．７４１６±０．０００４）,＾４０Ａｒ＾＾３９ 相似文献
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滇西南那邦变质基性岩地球化学与俯冲板片裂离 总被引：4，自引：1，他引：3
中缅边界那邦麻粒岩相变质基性岩地球化学特征表明其原岩是岩浆岩,并具有ＭＯＲＢ的特性,其岩石化学具有以下特征：岩石的ＴＦｅ／ＭｇＯ值低（１．１０～２．１７）,ＡＦＭ图解上显示拉斑玄武岩演化趋势;ＴｉＯ２含量（１．１４％～１．８１％）高稀土亏损、重稀土较有富集的配分形式,稀土元素和总量（∑ＲＥＥ）值十倍于球粒陨石（２４～５０μｇ／ｇ）,（Ｌａ／Ｓｍ）Ｎ＝０．４３～０．７５（Ｌａ／Ｙｂ）Ｎ＝０．４５～０ 相似文献
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武当地块基性岩墙群及耀岭河群基性火山岩的Sr,Nd,Pb,O同位素研究 总被引：9，自引：2，他引：7
武当地块基性岩墙群与耀岭河群基性火山岩的Ｓｒ、Ｎｄ、Ｐｂ同位素特征反映它们具相同的混合地幔源区。前者的（＾８７Ｓｒ／＾８６Ｓｒ）ｉ＝０．６９０５￣０．７０６１,εＮｄ（ｔ）＝－１．９￣５．０,Δ＾２０８Ｐｂ／＾２０４Ｐｂ＝３５．４９￣１９０．２６,Δ＾２０７Ｐｂ／＾２０４Ｐｂ＝４￣８５,Ｔｈ／Ｔａ低,Ｌａ／Ｙｂ变化大;后者的（＾８７Ｓｒ／＾８６Ｓｒ）ｉ＝０．６４８７￣０．７０７５,εＮｄ（ｔ）＝０ 相似文献
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青藏高原西部喜马拉雅期花岗岩类特征及岩石系列 总被引：5，自引：1，他引：4
青藏高原西部喜马拉雅期花岗岩类岩石组合为透辉石正长岩－透辉石花岗岩－黑云母（二长）花岗岩,主要造岩矿物有钾长石、斜长石、石英、黑云母、透辉石和角闪石。岩石化学成分富碱、高钾、Ｋ２Ｏ／Ｎａ２Ｏ比值大,微量元素富集Ｒｂ,Ｓｒ、Ｂａ、Ｔｈ、Ｕ和ＬＲＥＥ,Ｓｒ、Ｎｄ同位素组成具有幔源特征,岩石属于钾玄岩（ｓｈｏｓｈｏｎｉｔｅ）系列。 相似文献
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金沙江蛇绿岩带蛇纹岩中浅色岩类的成因 总被引：4，自引：0，他引：4
浅色岩类的岩石类型包括斜长岩和斜长花岗岩,它们均呈岩块状包裹于蛇纹岩中。浅色岩的正Ｅｕ异常明显,ＲＥＥ参数图解、Ｎｂ／Ｔａ和Ｚｒ／Ｈｆ值等均呈现分离结晶趋势,不相容元素Ｓｒ、Ｂａ、Ｎｂ、Ｔａ、Ｚｒ、Ｈｆ富集,相容元素Ｓｃ、Ｖ、Ｃｏ、Ｎｉ亏损,并与其寄主岩－蛇纹岩形成强烈的互补关系。这些特征表明,浅地是幔源超基性岩浆晚期结晶分异的产物。 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
14.
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