河南省西峡县高庄金矿床地质特征及找矿前景

朱阳关-夏馆断裂是一条长约400 km,深达上地幔的超壳深大断裂带,沿断裂带出露有较多的燕山期花岗岩(脉)体及一系列Cu、Au、Ag、Pb、Zn异常,有色金属、贵金属成矿作用明显。高庄金矿床赋存在二郎坪群含放射虫黄铁矿变细碧岩内,矿体成群成带分布在朱阳关-夏馆断裂次级断裂中,明显受断裂控制,近地表以石英脉型金矿为主,向下渐变为蚀变碎裂岩型金矿,矿体自地表向下明显变厚,金品位增富。其成因为海底火山喷流-岩浆热液-构造热液叠加改造形成的含金石英脉-蚀变构造岩型金矿。二郎坪群蛇绿岩套横贯河南省西南部,连续延伸约400 km(图1),含放射虫黄铁矿层广泛发育,Cu、Au、Ag、Pb、Zn异常分布较多,朱阳关-夏馆断裂的次级断裂中黄铁矿化、硅化、多金属硫化物蚀变明显,随着深部地质找矿的进一步开展,本区可成为我国重要的金多金属矿产基地。     

豫西南周庄铅锌银矿床地质和成矿流体地球化学

豫西南周庄铅锌银矿床是最近在豫西南铅锌银矿集区新发现的一处矿产地。矿床形成于印支期造山后板内构造-岩浆地质环境,工业矿体主要是东秦岭二郎坪群中充填于垂直造山带走向的断裂构造中的石英-铅锌银硫化物矿脉,热液成矿作用经历了石英-黄铁矿、石英-铅锌银硫化物、石英-方解石等早、中、晚3个不同阶段。矿石中以石英为主的脉石矿物捕获...     

蒿坪金矿成矿地质特征及成因浅析

蒿坪金矿产于下古生界二郎坪群大庙组底中碳硅质板岩及碳质云母石英片岩中,受层间断裂控制。矿化类型为石英脉型及构造蚀变岩型,矿化是在中温、弱还原,弱碱性,高盐度条件下进行的。该矿床是早古生代末期初始富集,中生代未期定位成矿的以变质热液为主又有岩浆热液参与的复合成因金矿。     

中冈底斯布东拉金矿床地质特征、控矿因素和找矿标志

布东拉金矿床是近年来在中冈底斯岩浆岩带新发现的少有的中型岩金矿床。矿床位于措勤弧后盆地的北西向和北东向断裂的交汇部位,矿体严格受断裂构造的控制,产于北西向次级断裂带中,呈脉状、透镜体状产出;矿体由石英脉和构造蚀变岩组成,主要矿石矿物为黄铁矿、黄铜矿、方铅矿、闪锌矿,以及自然金等;矿床围岩蚀变强烈,以黄铁绢英岩化为主;岩浆岩和构造是该矿床的主要控制因素;北西向构造、围岩蚀变、含硫化物石英脉、地球化学异常等可作为找矿标志。该矿床的发现丰富了冈底斯金矿床的矿床类型,对金成矿规律的总结具有重要意义。     

河南内乡县许窑沟金矿地质特征及成矿过程

河南许窑沟金矿位于东秦岭造山带朱阳关—夏馆断裂和瓦穴子—乔端断裂共同控制的二郎坪群地层中,矿体主要产于牧虎顶花岗岩岩体与火神庙组接触带中。矿石分为石英脉型和蚀变岩型2类,矿体围岩蚀变发育,蚀变类型较多,主要有硅化、绢云母化、绿泥石化、钾化、碳酸盐化、黄铁矿化、赤铁矿化。含矿石英脉主要包裹体类型包括富气和H2O-NaCl-CO2三相包裹体,成矿期的均一温度主要为310～350℃,盐度一般为2%～7%;成矿晚期均一温度主要为300～340℃,盐度为10%～15%。综合分析认为,许窑沟金矿成矿过程比较复杂,成矿过程中有沸腾作用,同时又存在大气水和岩浆水混合作用,为构造破碎带型的金矿。     

甘肃东沟金矿床地质矿化特征及找矿方向

东沟构造蚀变岩-石英脉型金矿床,位于关子镇-元家坪和娘娘坝-舒家坝两条韧性剪切带与天子山和磨扇沟花岗岩体的夹持区,金矿化严格受其次级近EW向断裂控制,后期断裂构造对矿体具一定破坏作用。矿石类型地表以构造蚀变岩型为主,向深部过渡为石英脉型,褐铁矿、黄铁矿、毒砂是主要载金矿物。围岩蚀变以硅化、褐铁矿化、黄铁矿化、绢云母化为特征。中基性火山岩、韧脆性断裂构造、中酸性岩浆侵入“三位一体”是控制矿床形成的基本条件,近EW向断裂蚀变带及延伸部位是找矿有利地段。     

平顶山金矿床的稀土元素地球化学特征

平顶山金矿床的矿石、石英脉、蚀变花岗岩、细晶闪长岩及蚀变闪长玢岩等的稀土元素地球化学特征是：蚀变花岗岩、矿石、石英脉三者的稀土配分曲线基本相似,轻稀土富集型而重稀土则相对较贫。而蚀变闪长玢岩脉及细晶岩脉的稀土总量较前三者高出许多,具较明显的铕负异常。这些特征指示了成矿热液可能来源于花岗岩侵入后的岩浆期后热液。     

南岭九龙脑矿田典型矿床构造解析:以淘锡坑钨矿床为例

南岭九龙脑矿田淘锡坑钨矿是赣南地区典型的石英脉型黑钨矿床,受断裂构造与花岗岩体控制。本文通过8个中段坑道填图,结合地表钻和坑内钻揭露,对含矿石英脉、矿脉组、矿体以及成矿花岗岩体的几何形态、结构构造进行仔细观测,统计矿脉及成矿后断裂产状并进行构造解析。淘锡坑黑钨矿石英脉矿体整体呈平直长板状,具有尖灭侧现,单脉之间以左行斜列为主,而矿脉组呈菱形网格状排列等特征;花岗岩体呈矩形块状、阶梯状。岩突以顶蚀和岩墙扩展两种方式由南东向北西侵位。矿床为多期多阶段的成岩成矿,断裂对花岗岩的侵位与成矿起到主导控制作用。本文综合分析并构建了淘锡坑钨矿构造-岩浆的成矿演化模式,即区域构造应力作用生成共轭断裂构造网格体系,然后岩浆侵位上拱被共轭断裂切割的"几何体"围岩移位而侵位,并沿共轭断裂体系内充填云英岩脉、含矿石英脉体,完成一次成岩成矿作用;区域构造再次活动使围岩与花岗岩体发生断裂,并再次诱导岩浆侵位,在早期花岗岩体和围岩内断裂中形成矿体和云英岩脉体,从而形成内带和外带含矿石英脉;成岩成矿后区域构造小规模错动、破坏岩脉与矿脉,但未改变岩脉矿脉的整体展布。     

内蒙红花沟金矿蚀变岩型金矿体控矿构造分析

红花沟金矿矿区内已发现40余条金矿脉和含金石英脉,它们均产于在区域Ⅰ级和Ⅱ级断裂构造(龙头山断裂)控制下侵位的燕山期龙头山花岗岩岩体与太古宙古老变质岩的内、外接触带上.蚀变岩型矿体是2000年发现和圈定出的新类型金矿体,分布在走向NW305 °的龙头山断裂的下盘,受其次级弧形构造所控制.分析认为沿龙头山断裂向上迁移的含金流体在运移到碎裂状糜棱岩化花岗岩后,在其中交代、充填并产生硅化、绢云母化和黄铁绢英岩化,形成蚀变岩型金矿体.晚阶段含金流体则在已蚀变的碎裂状花岗岩中充填成矿,进一步提高了蚀变岩型矿体和矿石的工业品位.     

河南乔端金矿床地质特征及成因探讨

乔端金矿床位于区域性乔端-瓦穴子断裂上盘的次级构造带中,矿体赋存于加里东期石英闪长岩中。矿床矿石类型包括蚀变岩型和石英脉型两种;矿床严格受构造破碎带控制,成因上与燕山期岩浆侵入活动关系密切。     

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     

PROSPECTING EXPLORATION

正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of