河南省肖畈钼矿地质特征及动力学背景

肖畈钼矿床是东秦岭-大别山地区典型的斑岩型钼矿床.与矿床有关的小侵入岩为肖畈岩体.岩体分两期侵入,第一期为花岗斑岩,第二期为斑状花岗岩.矿石中金属矿物以辉钼矿、黄铁矿为主,脉石矿物以石英为主,矿石构造有细脉状、浸染状及团块状.矿床成矿年龄为142 Ma.其与金堆城钼矿、南泥湖钼矿等斑岩型钼矿均形成于早白垩世,可归为东秦岭-大别山钼矿带第2成矿期,是印支期后大别造山带构造体制从挤压收缩向区域性伸展的成矿事件.     

中国东部中生代钼矿成岩-成矿时差

与岩浆成因相关的钼矿床成岩-成矿时差是确定矿床与岩浆岩成因关系的重要基础.本文根据收集的中国东部中生代典型钼矿床的成矿及相关岩体的同位素测年数据,详细讨论并定量厘定了钼矿的成岩-成矿时差分布特征.结果表明,钼矿成矿同步或略滞后于同源岩浆活动,中国东部整个钼矿成矿高峰的两个阶段时差介于0～10.0 Ma和0～15.0 Ma;对于单个钼矿床,其成岩-成矿时差集中在0～14.0 Ma,均值为3.9 Ma;从斑岩型钼矿床→斑岩-矽卡岩型钼矿床→矽卡岩型钼矿床→石英脉型钼矿床,成岩-成矿时差呈逐渐增加趋势,这与岩浆热液成矿过程的地质事实吻合.     

辽宁葫芦岛安昌岘钼矿地质特征及找矿标志

安昌岘钼矿为隐伏矿床.矿体产于夕卡岩中,呈似层状、透镜体状大致平行分布.钼矿石中的金属矿物主要有辉钼矿,其次为黄铁矿、磁铁矿、黄铜矿、方铅矿、闪锌矿等.非金属矿物主要有石榴石、透辉石、符山石、透闪石、阳起石、石英.围岩蚀变类型主要有夕卡岩化、硅化、绿泥石化、绿帘石化、阳起石化.与成矿有关的蚀变主要为夕卡岩化.侏罗纪钢屯超单元花岗岩是主要含钼矿源岩.安昌岘钼矿属夕卡岩型钼矿床.     

新疆东戈壁钼矿床地质特征及成矿热液作用阶段划分、矿物生成顺序研究

新疆东戈壁斑岩型钼矿床是西北地区发现的第一个特大型钼矿床,矿床产于下石炭统浅变质碎屑岩夹火山岩中,位于雅满苏大断裂附近.文章通过分析含矿脉体之间的交切关系及生成先后顺序,将东戈壁钼矿成矿期热液作用划分为4个阶段;根据金属矿物之间的穿插、交代、共边关系,确定了矿物生成的先后顺序.     

论金矿成矿与CO2相关性的实质

根据CO2的形成条件及其与Au的配合能力，金成矿系统矿物流体包裹体的气相成分，有代表性的金矿物的化学成分，具成因意义的共、伴生矿物，认为金成矿与CO2相关性的实质是CO与成矿物质形成羰基配合物、羰基氢配合物迁移至地壳浅部，由于温度、压力骤降，fo2剧增，上述配合物分解(CO、H2逃逸，氧化)形成金矿物沉淀富集成金矿床。     

东秦岭地区钼矿床铅同位索组成特征及成矿物质来源初探

东秦岭陕西金堆城—黄龙铺—河南南泥湖钼矿带,拥有驰名中外的金堆城斑岩型钼矿床,如近年来探明的南泥湖—三道庄—上房沟斑岩-矽卡岩型钼(钨)、钼(铁)矿床和黄龙铺碳酸岩脉型钼(铅)矿床等。无论从矿床类型、规模,还是从成矿地质条件和远景上看,该钼矿带无疑是我国最主要的钼成矿带之一。因此,在研究该钼矿带成矿地质条件的同时,进     

河北省丰宁撒岱沟门钼矿流体包裹体特征及其成矿背景研究

河北省丰宁撒岱沟门斑岩型钼矿,处于华北地台北缘的东段,是河北省内最大的钼矿床,撒岱沟门斑岩型钼矿主要与吕粱—五台期的中酸性岩、海西期的二长花岗岩和燕山期中酸性岩有关,钼矿主要产于二长花岗岩、石英正长斑岩中,一般呈岩株、岩墙状产出（黄典豪等,1996;范羽等,2014）。在结合华北板块北缘钼-铜矿床的成矿背景（黄典豪等,1996;代军治等,2008;魏然等,2013）,通过对承德市丰宁县撒岱沟门钼矿区地质特征和矿体的流体包裹体特征（代军治等,2007）的研究,对其成矿环境（吕古贤,2015）和成因（骆文娟等,2010）进行了分析探讨。撒岱沟门钼矿床,在成矿前期和成矿阶段包裹体主要是以气液两相为主,同时存在含CO2的三相,和CO2相的包裹体。成矿流体以岩浆水为主,晚期有大气水的混入。主成矿流体总体属于H2O-NaCl-CO2体系,主成矿期成矿包裹体的均一温度介于160~300℃、盐度介于2%~13.38%,成矿期流体的不混溶作用对辉钼矿的沉淀成矿产生了积极的影响。     

准噶尔北部希勒库都克斑岩钼铜矿床地质与成矿流体

希勒库都克斑岩铜钼矿床铜钼矿化与安山玢岩脉、英安玢岩脉有关,蚀变有钾长石化、绢云母化、绿帘石化等,向外发育绿泥石化、深部发育夕卡岩型蚀变。浅部以钼矿化为主,向深部铜钼矿化并存。与典型的斑岩型矿床相比,其石英中流体包裹体少而小,气体包裹体少,含CO₂包裹体及含子矿物包裹体发育,子矿物以NaCl为主,基本不出现KCl子矿物。钼富集处出现了富CO₂流体的沸腾,铜富集处出现了成群分布的含大子矿物包裹体,沸腾消失。钼的成矿主要与富CO₂成矿流体沸腾及斑岩型蚀变和夕卡岩蚀变有关,钼主要源于地壳,成矿温度为280~530℃,集中在300~400℃左右。铜主要与直接从深源基性岩浆出溶的高盐度流体及夕卡岩型蚀变有关,铜主要源于上地幔,主要成矿温度低于350℃。晚期流体的成矿温度为180~300℃左右。希勒库都克矿床成矿流体特征反映了壳源与幔源流体混合、岩浆热液与天水混合的特征。     

辽宁河坎子钼矿床地质特征及成矿远景预测

辽宁省河坎子钼矿床位于喜峰口—凌源多金属成矿带。从钼矿形成的控矿因素、成矿地质特征、矿床成因入手,分析钼多金属矿区钼矿床形成的主要地质因素、矿床形成的地质作用,预测区内成矿远景,指出河坎子钼矿床为斑岩型矿床,并具大中型矿床成矿远景。     

辽西杨家杖子-八家子钼多金属成矿带——典型钼矿床特征及找矿远景预测

辽西杨家杖子-八家子钼多金属矿成矿带钼矿床与燕山期中酸性岩体关系密切.产于花岗质岩类与碳酸盐岩地层接触带的钼矿床为夕卡岩型或斑岩-夕卡岩型钼矿床.产于花岗斑岩、长英质或中性火山岩内的钼矿床多为斑岩型钼矿床.不同类型钼矿床在成因、分布规律以及成矿元素的分带性上有着密切的时空关系.钼矿床的成矿物质来源于花岗岩,细粒花岗斑岩是主要成矿母岩.从成矿条件分析可确定,该钼多金属成矿带的找矿远景可观.     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

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.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

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.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

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).     

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     

METAMORPHIC PETROLOGY

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),     

SERIALS

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GEOPHYSICAL EXPLORATION

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-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

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-     

PETROLEUM GEOLOGY

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.)     

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