焦家式金矿水－岩交换作用─—成矿流体氢氧同位素组成研究

焦家式金矿位于胶东半岛西北部，矿体赋存于花岗片麻岩－花岗闪长岩类岩石断裂带内，呈破碎黄铁绢英岩化浸染状矿石。矿体中均伴有富含金的成矿前、后中基性脉岩。成矿作用包括乳白色块状黄铁矿石英和（或）伟晶石英脉阶段、含金硫化物石英阶段和方解石石英阶段。三个阶段石英δ￣（１２）Ｏ值平均为１２．４‰、１３．２‰和１４．４‰。计算的石英δ￣（１８）Ｏ＿（Ｈ＿２Ｏ）值平均分别为４．７‰、３．５‰和３．５‰。三个阶段石英流体包裹体水δＤ＿（Ｈ＿２Ｏ）值平均分别为－７３‰、－８０‰和－９２‰。经反演计算，提出成矿流体是中生代大气降水（δ￣（１８）Ｏ＝－１５．５‰，δＤ＝－１１５‰）与５ｋｍ以下深部中基性岩在３５０～４００℃时，有效Ｗ／Ｒ比值从０．０１至０．０５之间交换作用形成。     

五台山地区韧性剪切带型金矿成因

五台山地区韧性剪切带型金矿分布于晚太古代碰撞造山带中，与世界许多太古宙绿岩带型金矿具有相似的特征。研究表明：成矿流体的δ１８ＯＨ２Ｏ＝－２．１‰～４．９‰，δＤ＝－６９‰～－１１２‰，蚀变碳酸盐矿物的δ１３ＣＰＤＢ＝－２．０‰～－１．４‰，δ１８ＯＳＭＯＷ＝１０．０‰～２０．０‰；载金黄铁矿的δ３４Ｓ＝－３．７‰～５．６‰。成矿前流体具有中—高盐度，成矿期流体以富含ＣＯ２、近似海水的δ１８Ｏ和海相碳酸盐的δ１３Ｃ值，成矿后流体具有较高的盐度及可变的δ１８ＯＨ２Ｏ、δ１３Ｃ值。这种金矿成矿流体很难与某单一流体源相对应，它反映的多是变质流体与海盆地铁镁质岩石在成岩过程中饱含的热卤水混合的结果。综合有关资料，提出本区韧性剪切带型金矿形成于太古宙末期汇聚型地球动力学背景下的弧－陆、陆－陆碰撞过程中，金矿化作用和分布受碰撞构造边界的大规模逆冲型韧性剪切带控制。     

王台山地区韧性剪切带型金矿成因

五台山地区韧性剪切带型金矿分布地晚太古代碰撞造山带中，与世界许多太古宙绿岩带型金矿具有相似的特征。研究表明：成矿流体的δ＾１８ＯＨ２Ｏ＝－２．１‰－４．９‰，δＤ＝－６９－１１２‰，蚀谜面对得起盐矿物的δ＾１３ＣＰＤＢ＝－２．０－１．４‰，δ＾１８ＯＳＭＯＷ－１０．０－２０．０‰，载金黄铁矿的δ＾１４Ｓ＝－３．７－５．６‰。成矿前流体具有一高盐度，成矿期流体以富含ＣＯ２、近似海水的δ＾１８Ｏ和海相     

焦家式金矿水-岩交换作用——成矿流体氢氧同位素组成研究

焦家式金矿位于胶东半岛西北部，矿体赋存于花岗片麻岩－花岗闪长岩类岩石断裂带内，呈破碎黄铁绢英岩化浸染状矿石。矿体中均伴有富含金的成矿前、后中基性脉岩。成矿作用包括乳白色块状黄铁矿石英和（或）伟晶石英脉阶段、含金硫化物石英阶段和方解石石英阶段。三个阶段石英δ＾１８Ｏ值平均为１２．４‰、１３．２‰、和１４．４‰。计算的石英δ＾１８ＯＨ２ｏ值平均分别为４．７‰、３．５‰和３．５‰。三个阶段石英流体包裹体     

新疆望峰金矿成矿流体研究及其成因意义

新疆望峰金矿,产于中天山结晶基底中的韧性剪切带内。围岩蚀变和流体包裹体研究表明,成矿过程包括了３个阶段,从早到晚有石英黄铁矿阶段、多金属硫化物阶段和石英碳酸盐阶段,温度分别集中在３６０～５２０℃、２４０～３６０℃和１２０～２４０℃;矿化以第Ⅱ阶段为主。成矿流体的δ１８Ｏ值变化于１．１５‰～２．７０‰之间,属于变质热液与大气降水热液的混合流体。包裹体成分表明成矿流体来源较浅,但有利于金矿化;ＣＯ２／Ｈ２Ｏ比值多大于０．０２６,也有利于成矿。而包裹体捕获压力表明成矿作用发生在５．６～１．２ｋｍ深度范围,主要发     

东天山康古尔金矿床成矿流体地球化学特征及其来源

新疆康古尔金矿床是分布于晚古生代火山岩区受脆韧性剪切带控制的蚀变岩型金矿。该矿床成矿流体具有中低温度（３２０～１００℃）、中等ＮａＣｌ质量分数（１１４％～１７０％）、弱还原等特征。包裹体气相成分以Ｈ２Ｏ和ＣＯ２为主,液相成分中富Ｎａ＋、Ｃｌ－,而贫Ｋ＋、Ｆ－。成矿流体δＤ为－４５‰～－６６‰,δ１８Ｏ为－８３４‰～２９８‰,（８７Ｓｒ／８６Ｓｒ）ｉ值为０７０７７～０７１０６,反映了成矿流体由变质水、大气降水和岩浆水混合组成的特点     

河台韧性剪切带金矿床成矿物理化学条件研究及熔融包裹体的发现

河台韧性切带金矿床产于震旦系－志留为质岩系深大断裂糜棱岩带中,本研究首次在矿床含矿石英脉及糜棱岩中发现熔融包裹体,流体－熔融包裹体及有机包裹体。不同类型包裹体均一温度,有机包裹体为１６０℃,成矿流体属Ｋ＾＋－Ｃａ＾２＋－Ｍｇ＾２＋－Ｎａ＾＋－ＳＯ４＾２－ＨＣＯ＾２－４－ＨＣＯ３＾－４－Ｃｌ＾－体系,具中偏碱性,微量气体特征：Ｈ２Ｏ〉ＣＯ２〉ＣＨ４〉（或〈）Ｈ２〉ＣＯ〉Ｃ２Ｈ２〉Ｃ２Ｈ６〉Ｏ２〉ＨＪ     

山东省沂水汞丹山地块与深熔作用有关的变质流体

沂水汞丹山地块为一片麻岩－花岗岩穹隆,穹隆中心出露大片紫苏花岗岩和麻粒岩相表壳岩残留地层（或包体）,向北部、东部和南部外围过渡为角闪岩相片麻岩、斜长角闪岩和花岗质岩石,其中常见深熔脉体和伟晶岩脉。麻粒岩相表壳岩围岩很少含或几乎不含流体包裹体、而在深熔脉体、紫苏花岗岩和伟晶岩脉中含大量富ＣＯ２流体包裹体,少量Ｈ２Ｏ包裹体、ＣＯ２－Ｈ２Ｏ包裹体,偶见含固相（石盐、碳酸盐）的多相包裹体与富ＣＯ２包裹体伴生。早期富ＣＯ２包裹体（Ｉａ型）具有较高流体密度,而沿石英（石榴石）中穿颗粒裂隙分布的富ＣＯ２包裹体流体密度降低。富Ｈ２Ｏ包裹体大都沿裂隙分布,也属峰期变质后的退变质晚期产物。低密度富气相包裹体则多与ＣＯ２（Ｈ２Ｏ）包裹体组分的渗漏或部分爆裂有关。对深熔作用期间流体的作用进行了探讨,认为在中部地壳压力条件下,一种富ＣＯ２－Ｈ２Ｏ流体沿岩石页理面或裂隙渗流能产生石榴石／斜方辉石的部分熔融,Ｈ２Ｏ优先进入熔体,ＣＯ２进入共存的气相而分离,并可作为流体包裹体被捕获于石榴石或辉石包裹的石英和随后由硅酸盐熔体冷却结晶的长英质脉体石英中。根据矿物平衡和流体包裹体资料推断了峰期变质后岩石经历的Ｐ－Ｔ条件。     

安徽沙溪斑岩铜矿床成矿流体演化及分布规律

对安徽沙溪斑岩铜矿床流体包裹体进行了详细研究，得到气液包裹体的均一化温度为１００￣５００℃，盐度为２．０ｗｔ％￣６０ｗｔ％ＮａＣｌ，并且流体包裹体的成分和温度随时间、空间变化而呈现出一定的变化规律。对热液脉石英及其流体包裹体中Ｈ２Ｏ、ＣＯ２的氧、氢、碳同位素组成分别进行了测定，得到热液δ＾１８ＯＳＭＯＷ为＋３．５１‰￣＋５．５２‰，δＤＳＭＯＷ为－６０‰￣－８２‰，δ＾１３ＣＰＤＢ为－３．６１‰￣     

深源流体—老王寨金矿床含矿流体来源的一种可能性

老王寨金矿床含矿流体是一种富含矿化剂Ｃｌ＾－、ＣＯ２和Ｓ＾２－的高温高压深源流体。石英中流体包裹体的δ＾１８ＯＨ２Ｏ值在＋６．９１‰￣＋１１．７６‰之间，δＤＨ２Ｏ值为－６８．１０‰￣－１０１．１０‰之间，辉锑矿的δ＾３４Ｓ值为－０．１５‰￣－１．０３‰，方解石的δ＾１３Ｃ值为－０．３４‰￣－３．１２‰。研究结果表明，这种流体既不是岩浆热液也不是大气降水，而是一种深源流体。     

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