陕西省略阳县杨家坝多金属矿田成矿流体地球化学示踪

以陕西省略阳县杨家坝多金属矿床为例,通过对矿石中矿物流体包裹体特征的系统研究,流体包裹体分布表现以纯液相包裹体(A区)和大体积、大气相比原生气液两相包裹体(B区)为主的分区现象.A区原生气液两相包裹体的均一温度为184℃,成分为H2O;B区包裹体均一温度为245～348℃,主要集中在260℃、330℃,成分为H2O和C6H6.所测B区包裹体均一温度明显大于前人对该矿床所测得的最高温度293℃,说明有温度更高的还原流体参与成矿.结合秦岭造山带的构造背景和微量及稀土元素分析,初步认为该H2O-C6H6成分体系流体可能是伴随该区强烈构造运动沿深大断裂快速脉动上涌到地壳中的地幔流体;该流体作用导致壳幔叠加成矿,是秦岭造山带大规模改造成矿的序曲.     

阿尔泰造山带南缘金矿流体及其动力学分析

根据阿尔泰造山带南缘阿克提什坎、库马苏、塔斯比格、多拉纳萨依、阿克希克等十多个金矿区流体包裹体研究,含金石英脉中流体包裹体为液相、气相及多相包裹体。一般为5～8μm,形态呈不规则状、椭圆形和滴水状等。主成矿阶段温度变化范围在200～330℃。包裹体气相成分以CO、H2O、CO2、CH4为主,CO含量大于H2O。根据包裹体气相成分,岩金矿分为两类,一为CO2大于CO,集中于弧后盆     

内蒙古白乃庙铜金矿床流体包裹体研究

内蒙古白乃庙铜金矿床位于华北板块北缘增生型造山带,石英脉型和蚀变岩型矿体受 EW 向韧-脆性剪切带控制。成矿过程分为三个阶段:早阶段石英-黄铁矿,乳白色石英和粗粒黄铁矿变形、破碎;中阶段多金属硫化物充填胶结早阶段变形、破碎的石英角砾和黄铁矿裂隙;晚阶段为石英-碳酸盐细脉,穿切早中阶段脉体和矿物组合。冷热台显微测温结果显示,早阶段石英中原生流体包裹体的均一温度为248℃～380℃,盐度为4.34%～6.59%,次生包裹体均一温度为180℃～260℃,盐度为3.23%～4.18%NaCl eqv;中阶段石英中原生包裹体的均一温度变化范围为215℃～241℃,盐度为2.90%～4.18%NaCl eqv,与早阶段次生流体包裹体一致;晚阶段石英细脉和方解石中的流体包裹体均一温度为137℃～181℃,盐度为0.50% ～2.00%NaCl eqv。激光拉曼测试结果表明,流体包裹体气相成分为 CO_2、CH_4和 N_2。成矿流体为低盐度、低密度、富 CO_2的流体,当这种流体到达剪切带时,由于压力骤然降低发生以 CO_2逸失为特征的沸腾作用,导致成矿流体过饱和,成矿物质快速沉淀下来形成矿床。白乃庙铜金矿床成矿流体及矿床地质特征与造山型矿床一致,确证了造山型铜矿的存在并提供了实例。     

内蒙古白乃庙金矿流体包裹体与C-H-O-S稳定同位素特征及其对矿床成因的启示

白乃庙金矿位于中亚造山带南缘白乃庙岛弧区域,是华北地台北缘中段金成矿远景区的重要组成部分.本文通过白乃庙金矿床流体包裹体和C-H-O-S稳定同位素的系统工作,揭示其成矿物质来源、成矿流体性质以及矿床成因.流体包裹体测试均一温度(126.5～283.4℃)和盐度(0.88％ ～7.59％NaCl equiv)显示成矿流体...     

河南汤家坪钼矿床流体成矿作用研究

汤家坪大型斑岩型钼矿床位于大别造山带。对流体包裹体的岩相学、显微测温及激光拉曼显微探针分析表明,汤家坪钼矿床的流体包裹体可划分为富（含）CO2包裹体、水溶液包裹体和含子晶包裹体3类;均～温度集中在126,7-472．1℃,盐度集中在（0．18-14．21）wt％和（33．10～54．37）wt％．密度为O．38～1．21g／cm^3;子矿物含石盐及金属硫化物等。从矿体中心向外围．流体包裹体的温度、盐度有逐渐变小的趋势;从成矿早阶段到晚阶段．由高盐度低密度岩浆流体逐渐变为低盐度低密度流体,压力逐渐变小,深度变浅。辉钥矿的Re-Os模式年龄集巾在113～118Ma．表明成矿略晚于母岩岩体的成岩时代．其成岩成矿的构造背景为华北与扬子板块碰撞造山晚期的伸展构造体制。     

黔西南金矿成矿地质作用浅析

对黔西南(包括部分桂西北)金矿床的地质、稳定同位素和流体包裹体等研究表明,黔西南微细浸染型金矿属燕山期Au—Sb—Hg—Tl—U—Mo—As—萤石成矿系列,该系列内的所有矿产地均位于扬子陆块与右江造山带交界线两侧,垭都—紫云和水城—盘县—罗平两条深大断裂夹持的地热异常区内。各矿床的硫同位素和均一温度、盐度、密度、压力、深度以及包裹体成份等,都自西北向东南发生系列性变化,成矿时代也有自西北向东南由老逐步变新的趋势。成矿流体各地不同,扬子陆块内金矿床主要为大气水沿断裂带深循环作用形成,右江造山带的金矿床是混有大气水的封存热卤水。     

河南省大方山-葫芦峪金矿床流体包裹体研究

大方山-葫芦峪金矿区位于华北地台南缘与北秦岭造山带的衔接过渡带,矿脉赋存于构造蚀变破碎带中。矿床各成矿阶段流体包裹体主要为气液两相包裹体,通过对各阶段包裹体分析得知,主成矿阶段流体包裹体均一温度范围在197℃-305℃之间,流体包裹体盐度范围在10.98-0.88wt%NaCl 之间,包裹体气相成分中富含 H2 O 和 CO2,少量 O2和 N2,液相成分中相对富含 K＋、Na＋、Ca2＋、SO2-4、Cl-离子。流体包裹体研究表明,金矿床成矿流体为多来源的中低温流体。     

南秦岭汉阴北部长沟金矿床流体包裹体特征

长沟金矿位于南秦岭造山带汉阴北部地区,其矿体产出主要受韧性剪切带的控制。通过对矿区主要发育的2期石英脉流体包裹体特征研究表明:石英脉中主要发育气液两相包裹体,单相和三相流体包裹体少见;均一温度范围为175~385℃,含金石英脉流体包裹体均一温度为190~210℃;盐度变化较大,范围为0.88%~19.05%NaCl_(eq);成矿流体属于中-低温、中-低盐度流体。S_2期石英脉流体捕获压力范围为45.59~85.00 Mpa,流体捕获深度在1.69~3.15km,应为中浅深度成矿。S_2期石英脉应为与金矿成矿关系较为密切的主成矿期流体,S_3期石英脉为较高温度、低盐度,与成矿关系不大。     

东昆仑造山带海德乌拉铀矿床成矿流体特征研究

东昆仑造山带海德乌拉铀矿床是近些年西北地区最新探明的与火山岩有关的独立铀矿床,该矿床的发现为东昆仑造山带探寻热液型铀矿床提供了指示意义。本文选择与海德乌拉铀矿成矿期相关的透明矿物（粉红色方解石、紫黑色萤石及石英）作为研究对象,系统地开展C- H- O同位素和流体包裹体研究,查明该矿床成矿流体的来源与性质,并探讨矿床成因。研究结果表明,海德乌拉铀矿床成矿期石英中主要为H2O气液两相包裹体,少见CO2- H2O两相包裹体;在粉红色方解石脉、紫黑色萤石脉中流体包裹体均含H2O气液两相包裹体,在粉红色方解石脉中偶见纯液相包裹体,均未见到纯气相及含固相包裹体。成矿期粉红色方解石、紫黑色萤石及石英中包裹体均一温度范围分别为133~187℃（均值163℃）、127~204℃（均值169℃）、183~287℃（均值219℃）,盐度范围分别为1. 40%~7. 02%NaCleq（均值3. 65%NaCleq）、0. 53%~3. 06%NaCleq（均值1. 26%NaCleq）、7. 17%~17. 26%NaCleq（均值为11. 46%NaCleq）。流体包裹体气相成分以H2O为主,另含少量CO2等。C- H- O同位素实验数据表明,流体中δ13CFluid- V- PDB、δDFluid- V- SMOW、δ18OFluid- V- SMOW值的变化范围分别为1. 59‰~1. 00‰、71‰~63‰、0. 03‰~3. 72‰,表明成矿流体并非单一来源,可能为大气降水与岩浆水混合来源。此外,沥青铀矿的沉淀主要是由于流体与围岩的相互反应所引起的物理化学条件变化加上流体沸腾/CO2去气,最终导致了沥青铀矿等成矿物质发生大规模的卸载与沉淀。     

东昆仑东段哈陇休玛斑岩型钼矿成矿流体特征及成矿机制探讨

哈陇休玛钼矿位于东昆仑造山带东段,是近年来新发现的斑岩型钼矿床,规模已达中型。与成矿有关的岩体是晚三叠世花岗闪长斑岩流体包裹体的研究表明,石英-辉钼矿阶段流体包裹体类型主要有气液两相和含CO_2三相包裹体两种类型,前者盐水溶液盐度集中在6NaCI.eqv~12 NaCI.eqv间,后者盐度较大主要集中在16%NaCI.eqv~20%NaCI.eqv,该阶段包裹体均一温度集中于260℃~360℃;石英-多金属硫化物阶段流体包裹体主要以气液两相为主,包裹体均一温度集中于200℃~260℃,盐度集中在6%NaCI.eqv~10%NaCI.eqv。成矿流体由中高温、中-低盐度、富CO_2的流体向中低温、低盐度、低CO_2流体演化。沸腾流体包裹体组合的存在暗示了成矿流体的沸腾作用,可能由于压力急剧降低而形成。通过等容线相交法获得沸腾包裹体组合捕获时的压力为84MPa~120 MPa之间,成矿深度估算为3.2km~4.5km。总体上,成矿流体由中高温、中-低盐度、富CO_2的流体向中低温、低盐度、低CO_2流体演化。该矿床形成于东昆仑造山带印支晚期后碰撞环境,成矿花岗闪长斑岩体主要源自下地壳的部分熔融,金属Mo主要来源于下地壳底部,部分萃取于上部地壳,成矿流体中含CO_2组分是大陆环境含Mo岩浆系统的普遍特征。     

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.     

Définition d'une limite multicritère ; stratigraphie du passage Campanien–Maastrichtien du site géologique de Tercis (Landes,SW France)Definition of a multi-criteria boundary; stratigraphy of the Campanian–Maastrichtian interval of the geological site at Tercis (Landes,SW France)

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.     

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.     

Late Wuchiapingian (Late Dzhulfian,early Late Permian) limestone olistolites within the Tertiary flysch of Glypia Unit (Mount Parnon,central–eastern Peloponnesus,Greece)

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.     

PALEONTOLOGY

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.)     

GEOCHEMICAL EXPLORATION

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.)     

MICROPALAEONTOLOGY

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.)     

PETROLOGY

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.,     

ENVIRONMENTAL GEOLOGY

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