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1.
广东茂名地区二叠以状硅质岩成因地球化学特征及其沉积环境意义 总被引：2，自引：0，他引：2
徐跃通 《西安地质学院学报》1997,19(3):27-33
在广东茂名地区二叠系地层中存在地导整合产生的层状硅质岩。硅质岩富Ｆｅ，Ｍｎ，相对贫Ａｌ；富集Ａｓ，Ｓｂ，Ｂｉ，Ｇａ等微量元素，稀土元素总量低，Ｃｅ弱负异常，重稀土相对富集，δ＾３０Ｓｉ值变化范围为０．０００３～０．０００７，。δ＾１８Ｏ值变化范围为０．０１４８～０．０２２３，均具热水沉积硅质岩的地球化学特征，在Ａｌ－Ｆｅ－Ｍｎ－（Ｎｉ＋Ｃｏ＋Ｃｕ）三角图上，本区硅质岩均属于典型的热水积硅质岩，硅质 相似文献
2.
西秦岭寒武系金矿床中硅岩的地质地球化学特征及其沉积环境意义 总被引：31，自引：4，他引：27
西秦岭寒武系中的硅岩是拉尔玛－邛莫层控金矿床的主要赋矿岩石之一。含矿硅岩呈块状、条带状、层纹状、多孔状和同生角砾状等。硅岩单层厚度一般为３０～２００ｍ。主要成分ＳｉＯ２平均含量高达９５．３０％,其余为ＦｅＯ、Ｆｅ２Ｏ３和有机炭等。硅岩的Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）比值低于０．３（平均０．１５３）,投点于Ｆｅ／Ｔｉ－Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）图解和Ａｌ－Ｆｅ－Ｍｎ三角图解上,均落于热水沉积物区。硅岩中微量元素十分丰富,不仅含有具基性、超基性特征的元素群（如Ｃｕ、Ｃｒ、Ｐｔ、Ｐｄ、Ｏｓ等）,而且还含有具酸性特征的元素群（如Ｗ、Ｍｏ、Ｕ等）。硅岩中稀土以总量（３．２９～１００μｇ／ｇ）低和铈亏损为特征。经北美页岩标准化后的稀土比值随原子序数的增大而增大。硅岩的δ１８Ｏ值为１７．６０‰～２３．２４‰,据此得到它形成的温度为７０．９℃～１１８．１℃。硅岩的δ３０Ｓｉ值主要为＋０．４‰～＋０．８‰。上述硅岩的特点均显示其与喷流热水沉积作用有关。硅岩中Ｐ２Ｏ５含量、Ｓｒ／Ｂａ比值、δＣｅ值以及δ３０Ｓｉ值表明,它主要是在深海—半深海环境下形成的。 相似文献
3.
江西东乡矿区沉积硅质岩的地球化学特征和成因 总被引：9，自引：2，他引：9
江西东乡矿区石炭系地层中存在三层与地层整合产出的层状硅质岩。硅质岩富Ｆｅ，Ａｓ，Ｓｂ，Ｂｉ和Ｇａ；稀土元素总量低，Ｃｅ呈弱负异常，重稀土相对富集，δ＾３０Ｓｉ值变化范围为０．５‰－０．８‰，δ＾１８Ｏ变化范围为１２．５４‰－２１．１１‰。硅质岩地球化学特征表明其成因为介于热水沉积与生物沉积之间的过渡类型。 相似文献
4.
蔡家营铅—锌—银矿床的稳定同位素地球化学研究 总被引：3，自引：0，他引：3
河北蔡家营矿床是大型中温热液充填－交代脉型铅－锌－银矿床。其硫化物的δ＾３４Ｓ值为２．２‰－７．８‰，同世代共存的１０个硫化物对的Δ＾３４Ｓ值表明，Ｆｅ－（Ｚｎ、Ｐｂ）－Ｓ系统的硫同位素非平衡分馏占主导，硫是岩浆（为主）与老变质岩层硫的混合来源。石英及其流体包裹体的δ＾１８ＯＳＭＯＷ和δＤＳＭＯＷ值（‰）按混合模式计算表明，成矿流体为混合的岩浆和大气降水，早期成矿流体以岩浆为主，尔后则变为以大气降 相似文献
5.
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
6.
张立生 《沉积与特提斯地质》2000,20(2):74-82
脉冲黝铜矿型铜矿床是产于兰坪－思茅盆地中的一种新的铜矿床类型。碳酸盐及ＣＯ２包裹体的δ＾１３Ｃ值大多在－４‰～－７‰之间变化,显示碳来自地幔。矿石中铅同位素组成与盆地中喜马拉雅期碱性岩长石中铅的同位素组成一致,方解石和铁白云石的＾８７Ｓｒ／＾８６Ｓｒ比值接近或稍高于碱性岩的＾８７Ｓｒ／８６Ｓｒ的比值,显示矿石锶、铅与碱性岩锶、铅是同源的,均来自于上地幔。硫化物中硫的δ＾３４Ｓ值大多集中在０～－４‰ 相似文献
7.
湖南大庸慈利一带下寒武统黑色页岩中海底喷流沉积硅岩的地质特征 总被引：12，自引：3，他引：12
湘西北大庸慈利一带下寒武统黑色页岩中的硅岩，分布上受深断裂控制，具多孔状构造，微量元素Ｓｅ、Ａｓ、Ｂａ含量较高，Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）比值为０．１５～０．３２，稀土元素ΣＲＥＥ含量大于围岩的数倍，Ｃｅ亏损，δ１８Ｏ（对ＳＭＯＷ）值为１７．６２‰～２２．９１‰。这些特征表明，该硅岩是一种典型的喷流岩，并构成湘西北镍钼多金属矿床的容矿岩系 相似文献
8.
夏杖子金矿严格受构造破碎带控制，围岩蚀变主要为钾长石化、黄铁矿化、硅化和碳酸盐化。矿石中自然金有显微金和次显微金两种状态，金的成色为８３５～９２９；矿石包裹体成分主要以Ｈ２Ｏ为主，另含有ＣＯ２、Ｋ＋、Ｎａ＋、Ｆ－、Ｃｌ－和ＳＯ２－４等离子；矿石的稳定同位素组成：δ３４Ｓ为－２３．３８‰～－１４．４７‰，δＤ为－９１．７‰～７３．１‰，δ１８ＯＨ２Ｏ为５．６８～６．２５‰，２０６Ｐｂ／２０４Ｐｂ为１６．４１１～１６．６１５，２０７Ｐｂ／２０４Ｐｂ为１５．２２８～１５．２５６，２０８Ｐｂ／２０４Ｐｂ为３６．２６８～３６．３５６；矿石、脉岩和岩体具有相似的ＲＥＥ、Ｋ、Ｒｂ、Ｓｒ及微量元素地球化学特征。矿床中金的富集与成矿构造、围岩蚀变、矿化期次和矿石类型等多种因素有关，成矿作用发生于燕山晚期（１０５．４±７．２Ｍａ），成矿热液主要为岩浆热液，成矿物质来源于硅铝壳中下部太古代结晶基底，矿床成因为中－低温热液金矿床。最后对矿床的找矿标志进行了总结，指出了找矿方向，认为夏杖子金矿具有较好的找矿远景，尤其是矿床深部 相似文献
9.
本文通过钢铁工业废水淋溶钢铁工业渗漏区土壤，不同ｐＨ值，不同含Ｃａ＾２＋，Ｆ＾－浓度与放心水与工业淋溶各种土壤，以及电厂冲灰水淋溶粉煤灰的三种试验，讨论废水中Ｃ６Ｈ５ＯＨ、ＣＮ＾－ＡＳ、Ｃｒ，Ｐｂ，Ｚｎ，Ｈ２Ｓ，ＢＯＤ，ＣＯＤ，Ｆ＾－，Ｃｌ＾－，ＳＯ＾２－Ｒ，ＮＯ＾－３，ＮＨ＾＋４，Ｎａ＾＋和硬度等的污染与自净规律，并提出了防治地下水污染的措施。 相似文献
10.
扬子板块东南大陆边缘上震旦统热水成因硅质岩的地球化学标志 总被引：1，自引：0，他引：1
晚震旦世时,在扬子板块东南大陆边缘地带发育一套层状硅质岩建造,岩石化学成分纯净,ＳｉＯ２含量在９０％以上,其它化学成分含量均很低。但Ｆｅ和Ｍｎ相对富集,而Ａｌ,Ｔｉ,Ｍｇ相对贫乏。微量元素含量变化大,大部分微量元素含量相对地壳克拉克值偏低,仅Ｕ,Ａｓ,Ｓｂ,Ａｇ,Ｂａ等富集。岩石的δ＾３０Ｓｉ为０．０‰～０．７‰,δ＾１８Ｏ为２０．２‰～２３．６‰,δ＾３０Ｓｉ和δ＾１８Ｏ值及岩石的形成温度清楚地 相似文献
11.
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
12.
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
13.
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
15.
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
16.
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
17.
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
18.
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
19.
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
20.
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