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1.
本文对污牙钨矿区矿石、蚀变围岩、地层围岩及花岗岩进行了微量元素分析,分析结果显示,污牙钨矿床大多数矿石和蚀变围岩样品的Hf/Sm与Th/La值小于1,少部分蚀变围岩的Hf/Sm与Th/La值大于1,表明成矿流体以富Cl热液体系为主,部分显示富F特征,成矿流体具有多源性。云英岩化围岩及矿石与地层围岩样品的微量元素特征相似,主要显示变质成因;其它类型矿石及蚀变围岩样品微量元素特征与地层围岩样品差别较大,可能非单一变质热液作用的产物。类矽卡岩矿石中典型接触交代矿物符山石的大量存在,暗示岩浆热液参与成矿。在微量元素蛛网图上,蚀变围岩和电云英岩型矿石样品皆不显示Zr-Hf亏损,少数样品Ta-Nb也无异常,特征与地层围岩不同,与花岗岩样品相似,支持了岩浆热液作用的存在,污牙钨矿床很可能为变质热液与岩浆热液复合叠加成因。污牙矿区花岗岩和赋矿围岩,W元素均显示富集特点。 相似文献
2.
通过因子分析、相关分析和聚类分析，研究了巴彦温多尔金矿矿石和围岩样品12种元素的组合特征。结果显示，矿石中金与其他11种元素的相关程度很低，而围岩中金与银有较强的相关性。围岩和矿石的元素组合也有明显差别，围岩样品代表控矿构造带的矿化背景，矿石样品代表成矿时的元素组合。 相似文献
3.
相山、下庄两个铀矿田主要赋矿围岩的稀土元素特征极具相似性,显示出壳源型的特点。但它们的矿石稀土元素特征有很大的不同,相山铀矿田矿石稀土元素特别是重稀土元素含量与铀含量呈正相关,负铕异常和围岩相同。而下庄铀矿田矿石亏损稀土元素尤其是轻稀土元素,负铕异常比围岩更强烈,与幔源辉绿岩、正长岩的稀土元素分布模式相近。两矿田矿石稀土元素含量上存在明显差异的同时,都具有比其围岩LREE/HREE比值大幅度降低的特点。结合区域地质演化,认为两铀矿田矿石稀土元素具有不同的特征,但成矿流体都具有幔源性质,矿床都是在白垩—第三纪地壳拉张环境下形成的。 相似文献
4.
湖北鹤峰县杨家坪滑石矿位于走马—东山峰背斜南西段之南东翼，是新发现的具有中型规模的滑石矿矿床。通过对滑石矿矿床地质特征及成因进行综合研究和分析，认为矿体赋矿层位为下震旦统陡山沱组三段中上部，分为黑滑石、白滑石两层矿，两者上下相距7～10 m,均呈似层状大致与围岩整合产出，矿石具沉积特征的鲕粒结构。矿石自然类型为块状滑石、片状滑石，黑滑石矿工业类型为白云石—滑石型，白滑石矿不具备工业价值。矿体特征、矿石成分、矿石结构特征以及稀土配分模式等共同表明，矿石为同生海相沉积成因，而矿石的片理化构造显示矿床叠加有后期的变质变形作用，矿床类型为沉积改造型滑石矿床。研究成果可为走马—东山峰背斜一带滑石矿进一步找矿和研究提供依据和支撑。 相似文献
5.
相山、下庄铀矿田稀土元素特征对比 总被引：1，自引：0，他引：1
为了从大的区域上探讨铀矿的成矿作用,本文分别采集了相山、下庄两个铀矿田的围岩和矿石样品并用ICP-M S方法进行测定。结果发现两个铀矿田的围岩REE特征均为LREE富集型,具有明显的负铕异常。相山矿田的矿石富集REE特别是HREE,并且与铀含量呈正相关关系,矿石和围岩的负铕异常相同;下庄矿田的矿石亏损REE尤其是LREE,具有比围岩更强烈的负铕异常。认为两矿田的围岩都是由沉积岩为源岩的地壳物质部分熔融形成的,ΣCO2是两个铀矿田的主要矿化剂,也是铀和REE运移的主要载体,造成两矿石REE特征不同的主要原因是相山矿田围岩蚀变以酸性为主而下庄铀矿田围岩蚀变以碱性为主。 相似文献
6.
东沟坝多金属矿床喷流沉积成矿特征的稀土元素地球化学示踪 总被引：31，自引：5，他引：26
为了进一步研究东沟坝矿床的喷流沉积成矿特征,对东沟坝矿床矿石及围岩的稀土元素进行了ICP-MS测定。东沟坝矿床矿石普遍显示明显的Eu正异常和弱的Ce负异常,说明成矿热液为温度较高(250℃及其以上)、相对还原的流体。Eu正异常和弱Ce负异常同时在矿石中发育,说明矿石沉淀时较高温度的热流体与少量的海水发生了对流混合。根据矿石与围岩的稀土配分模式的相似性及矿石铅、硫同位素组成特征,推断成矿金属元素主要来自赋矿围岩。根据矿石中大量发育重晶石和矿石普遍具有的LREE富集、明显的Eu正异常和弱Ce负异常的事实,推断同生成矿流体中大量SO4^2-的出现与岩浆脱气作用有关。 相似文献
7.
本文主要叙述了白银厂矿床围岩和矿石的显微构造特征,认为围岩和矿石具有相同的变形、变质特征,说明它们经历了相同的变形和变质作用历史,可作为矿床同生成因的证据。 相似文献
8.
河南桐柏围山城金银成矿带成矿物质来源:
铅同位素证据 总被引：1，自引：0，他引：1
围山城金银成矿带出露有破山银矿床、银洞坡金矿床和银洞岭银矿床等三个大型金银矿床,均受地层和构造的双重控制,赋矿地层为新元古界歪头山岩组,河前庄背斜是成矿带的主要控矿构造.围岩地层歪头山岩组的铅同位素组成具有整体富Th亏U、低μ高ω的特征,与围山城金银成矿带的矿石铅整体富Th亏U、低μ高ω的特征一致.经过年龄校正后,把成矿带内的围岩地层和岩体的全岩铅同位素样品与矿石铅同位素对比分析发现,围岩歪头山岩组与矿石关系最为接近,其次为燕山期梁湾花岗岩体.成矿带的矿石铅具有混源特征.可以认为围岩歪头山岩组和梁湾花岗岩体共同为成矿带提供了铅源及成矿物质. 相似文献
9.
黔东南平秋金矿微量与稀土元素地球化学特征及意义 总被引：1，自引：1，他引：0
应用电感耦合等离子体质谱(ICP-MS)对黔东南平秋金矿浅部含金石英脉矿石、近矿围岩以及远矿番召组岩石的微量及稀土元素进行系统测定,结果表明:矿石中Au,As和Sb等成矿元素与围岩和地层相比发生了相对富集.R型聚类分析呈现出Au与壳源物质As,Pb和Sb等低温元素有密切的成因联系,表明金可能主要来源于地壳.根据微量和稀土元素特征分析可以将石英脉矿石分为两种类型,一类以样品k2,k4为代表的含金石英脉矿石与近矿围岩和赋矿地层岩石的微量元素变化趋势和稀土元素配分模式基本一致,表现出与围岩地层的一致性和继承性;另外一类英脉矿石(样品k1,k3)的微量及稀土元素地球化学特征与围岩有明显差异,轻重稀土分异不显著,Eu异常不明显,更接近下地壳或上地幔的稀土组成特征.综合分析认为该矿床含金石英脉矿石与围岩存在一定的成因联系,其成矿物质和成矿流体除了来源于赋矿地层外,可能有部分深部流体参与成矿. 相似文献
10.
《地质科技情报》2017,(2)
选取一个含金采样剖面,对旧房梁金矿床的成矿流体性质和成矿物质来源进行了探讨。研究结果表明,旧房梁金矿床产于陕西勉略宁三角地区中新元古界碧口群,矿体的分布和产状受地层岩性和韧性剪切带的强烈控制,矿床成因类型为绿岩型金矿床。对矿石及其顶底板围岩的主微量元素和稀土元素地球化学特征及其成矿作用的研究表明:与Au含量正相关性较好的元素有Ag、Hg、Bi、Mo;在成矿过程中,矿石和围岩的Al_2O_3、TFe_2O_3及高场强元素含量较稳定;大离子亲石元素含量在矿石及矿体底板围岩中相对亏损,在矿体顶板围岩中富集;亲硫元素含量表现较为复杂,Pb含量在矿体顶板围岩及氧化矿石中富集,Mo、Hg含量在矿石中普遍升高;同时伴随岩石质量的亏损;稀土元素配分模式显示矿石及近矿围岩相对于远矿围岩具有正Ce异常和负Eu异常的特征。上述特征均表明成矿流体具有高温还原性的特点。结合矿床流体包裹体和硫同位素等特征,认为该矿床的成矿物质来源可能与碧口群地层有关,其成矿过程可能与澄江期在区内广泛形成的NNE向韧性剪切变形有关,构造矿化蚀变对围岩物质组分具一定继承性和差异性。 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.
15.
Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
16.
正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.) 相似文献
17.
正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology, 相似文献
18.
正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.) 相似文献
19.
正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se- 相似文献
20.
正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with 相似文献