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1.
川东南脉状萤石-重晶石矿床流体包裹体研究   总被引:2,自引:0,他引:2  
川东南脉状萤石──重晶石矿床主要产于下奥陶统碳酸盐岩中,其成矿与岩浆活动无明显联系.成矿温度较低,成矿流体富含NaCl和H_2O,CO_2和CH_4的含量较低,N_2,O_2及H_2的含量甚微。成矿介质水主要来源于地层水(如封存的海水、盆地压实脱水等)及大气降水,成矿温度、δ ̄D值、盐度、Na ̄+/K ̄+比值以及矿石中有机包裹体的在在均表明本区萤石和重晶石的成矿流体类似于密西西比河谷型矿床的成矿热卤水,其形成与介质水溶滤本区寒武系蒸发岩有关。  相似文献   

2.
河北宽城峪耳崖金矿床地质地球化学特征及成矿物质来源   总被引:13,自引:1,他引:13  
峪耳崖金矿是冀东地区与中生代花岗岩有关的金矿床的典型代表,其成矿岩体具有明显的陆壳改造型花岗岩特征,成矿热液富CO2并具有较高的K^+,Ca^2+,Cl^-和HCO3^-,成矿温度集中于280-330℃,压力变化于111.4-30.4MPa,成矿流体以岩浆水为主导,成矿热液及成矿物质,主要来自岩浆体系。  相似文献   

3.
香花岭花岗岩不同岩相的岩石化学、微量元素,元素对比值和包裹体温度,压力与成分等方面的研究表明:香花岭花岗岩为H2O-F-CO2-Cl流体类型,属超临界流体,在超临界流体作用下,岩浆体系内熔体的粘度,内压,组分活动性及含量,胡岩浆演化呈系列变化,导致岩浆体系内的成分强烈分异成层;Nb,Ta等成矿元素,随岩浆体系内超临界流体的聚集而富集,随体系内射气分异作用的发生而矿化,成矿作用发生在岩浆期。其成岩成  相似文献   

4.
矽卡岩矿床的研究现状   总被引:11,自引:0,他引:11  
本文评述了矽卡岩矿床类型划分、矽卡岩形成的物理化学条件、成矿流体以及矿物成分与矿化关系的某些进展。镁矽卡岩形成于各种深度,而钙矽卡岩则形成于较浅和较低温的环境;限制矽卡岩形成的主要参数是CO_2、深度以及岩浆期后诸元素的活度(如Mg ̄(2+)、Ca ̄(2+)…)、pH和E_h值。当前已应用非平衡热力学去研究矽卡岩成岩成矿过程。接触交代带中存在两种流体,一种来自岩浆,另一种是天水循环来源;同位素资料提供水/岩反应的信息,而S、Pb、Sr等同位素资料提供矿质来源的标志。矽卡岩矿物如辉石、石榴石的化学成分与矿化关系密切,可以指示矿化类型。文中总结了矽卡岩型金矿特点,其蹄、铋矿物及退化蚀变是重要的找矿标志。含矿流体及成矿动力学是今后研究的重要方向。  相似文献   

5.
北塔山金矿床成矿流体成因及金沉淀机制的探讨   总被引:6,自引:0,他引:6  
北塔山地区金矿床及矿点的含金石英脉与闪长玢岩、闪长岩及斜闪煌斑岩等岩脉及小岩体有密切的空间关系,其一般产于岩脉内部及其接触带附近。石英中流体包裹体研究表明成矿流体为近中性低盐度和富CO2的K^+ ̄N^+(Ca^2+)-Cl^-型热液,推测主要属于来自深部的变质流体。金的成矿具多阶段特征。早期中-高温阶段减压引起CO2和H2S等组分溶解度减小和强烈挥发应是金沉淀的主要机制。晚期中-低温阶段,降温引起  相似文献   

6.
河南前河金矿床地球化学特征   总被引:8,自引:0,他引:8  
李莉  卿敏 《黄金地质》1999,5(3):75-80
对前河金矿微量元素、稳定同位素、流体包裹体研究表明,矿石中金与砷、钨、钼相关性较强,矿体在垂向上微量元素分带性明显。成矿流体以岩浆水为主,并有大所降水的混合。成矿物质主要由深源岩浆提供,并有浅部物质参与。成矿流体属Na^+-K^+-Cl^--SO4^2-型,而且气相成分中CO2含量较高。  相似文献   

7.
赣西卡林型金矿床流体包裹体地球化学   总被引:4,自引:2,他引:4  
赣西卡林型金矿床的包裹体地球化学研究表明,金矿主成矿温度为100~200℃,平均150℃左右,成矿流体盐度为1.9wt%NaCl~8.6wt%NaCl,成矿压力为247×105Pa~608×105Pa,成矿流体属K+-Ca2+-SO2-4-(F-)-CO2型,pH为3.6~4.1,是以大气降水为主,混有建造水及少量岩浆水的混合流体。研究认为,区内金矿主要是以金硫络合物形式,在较高温度(220~300℃)体系为还原态的条件下进行迁移,温度降低为150℃左右,fs2较低,有黄铁矿及富砷黄铁矿存在时,在低压较氧化的有利构造处沉淀富集成矿。  相似文献   

8.
吉林小西南岔金铜矿床流体包裹体及成矿作用研究   总被引:8,自引:1,他引:8  
李荫清  陈殿芬 《矿床地质》1995,14(2):150-173
该矿床流体包裹体丰富,为2相气液、1相液体、少数含子晶多相和含液态CO_2三相包裹体。包裹体液相中富Na ̄+、Cl ̄-和SO,气相中H_2O占优势,CO_2次之。属NaCl-H_2O体系。包裹体同位素分析表明,成矿流体为岩浆水和大气降水的混合流体。在温度高于360~400℃的中性—弱酸性热流体中,Au和Cu的络合物呈迁移状态,在温度低的弱酸—酸性的较还原环境下,围岩产生广泛的石英-绢云母化,导致Au、Cu络合物分解,沉淀出大量Au和Cu。  相似文献   

9.
香花岭花岗岩不同岩相的岩石化学、微量元素、元素对比值和包裹体温度、压力与成分等方面的研究表明:香花岭花岗岩为H2O-F-CO2-Cl流体类型,属超临界流体。在超临界流体作用下,岩浆体系内熔体的粘度、内压、组分活动性及含量,随岩浆演化呈系列变化,导致岩浆体系内的成分强烈分异成层;Nb、Ta等成矿元素,随岩浆体系内超临界流体的聚集而富集,随体系内射气分异作用的发生而矿化,成矿作用发生在岩浆期。其成岩成矿作用为一连续过程。在这一过程中,岩浆的结晶分异作用和交代、熔蚀作用并存,沉淀作用和溶解作用交替,实质上是岩浆体系的分异作用或自然组织作用过程  相似文献   

10.
S,Pb,C,O和H同位素研究表明,安家营子矿田金矿成矿物质主要来深部岩浆源,成矿流体为再平衡岩浆水,与金矿有关的安家营子二长花岗岩体为下地壳重熔成因,属金铜系列花岗岩类,金矿成矿年龄为120~130Ma。  相似文献   

11.
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.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
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   

13.
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   

14.
HYDROGEOLOGY     
正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level  相似文献   

15.
正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),  相似文献   

16.
17.
正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-  相似文献   

18.
正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-  相似文献   

19.
正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)  相似文献   

20.
GEOCHEMISTRY     
正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861  相似文献   

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