贵州万山特区竹山冲脉型重晶石矿构造控矿规律初探

竹山冲重晶石矿呈脉状、楔状陡倾角产于板溪群水江组板岩内的ＮＥ、ＮＮＷ及ＳＮ向断裂破碎带中,矿脉一般长数１００ｍ,厚０．４￣１．２ｍ,成群产出,含ＢａＳＯ４ ９５％以上。矿体受多期构造作用控制,ＮＥ向区域性大断裂形成的“多”字型次级断裂破碎带是重晶石矿的主要导矿、容矿构造,颇具区域找矿意义。     

西伯利亚地台西南部地区金矿带的地质环境和形成条件

在阿尔丹－斯坦洛沃依地盾的西伯利亚地台西南部地区划分出四个金矿带：（1）Ket-Kep带（主要由矽卡岩型、石英脉和网脉型、碳酸岩中的伊利石－褐铁矿型以及伊利石－绢云母交代型矿床或矿点构成）；（2）Ulkan带（伊利石－云母交代和石英脉型）；（3）Dzhugdzhur带（石英脉型和矽卡岩型）；（4）Dzhugdyr带（石英－硫化物脉型）。含矿矽卡岩成矿时代为中生代，而与石英和石英－硫化物脉型有关的矿化形成于晚元古代、古生代和中生代。大多数中生代的金矿化都与岩浆作用有关。含金岩石的流体包裹体研究结果表明，高温成矿过程主要发生在Dzhugdzhur带的矽卡岩（500－715℃）和Ket-Kep带的热液交代型岩石（510－530℃）中，这些矿石的矿物流体包裹体中的水溶液盐度高达40％NaCl当量，其子矿物主要为Na,K,Ca的氯化物，并以存在CO2为特征。Ket-Kep带内高温（高达465℃）和中温条件形成的石英脉和网脉中的流体包裹体盐度达32％NaCl当量，包裹体中有时含低密度的CO2。Dzhugdzhur带中的含金石英脉形成于225－230℃，为低盐度成矿溶液（1％－2％NaCl当量）。Dzhugdyr带中含金石英－硫化物脉的成矿温度为260－390℃，成矿溶液为低盐度（1．5％－7．5％NaCl当量）KCl水溶液。Ulkan带石英脉的成矿流体中含K－Na氯化物物种，所测定的盐度值为2％－10％NaCl当量，成矿温度在220－280℃之间。     

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。     

内蒙古乌拉山地区花岗伟晶岩脉的年代学研究

乌拉山地区的地质构造演化历史悠久,区内褶皱、断裂活动强烈,特别是从太古宙到印支期,伴随着山前大断裂的多次活动,形成了多期次的岩浆侵入体或岩脉(中国人民武装警察部队黄金指挥部,1995)。仅花岗伟晶岩脉就有上千条,它们呈近EW向分布在乌拉山南缘,绵延几十公里,蔚为壮观。其单条岩脉最长2km以上,最厚     

小秦岭西段稀土矿特征及找矿远景浅析

小秦岭西段是重要的稀土元素成矿地段。受华阳川断裂、金堆城-青岗坪断裂和太古代变质基底等因素的控制产出了区内碳酸岩型和伟晶岩型2类稀土矿化。碳酸岩型稀土矿含矿主岩为各类碳酸岩脉,以小河断裂为界,南北含矿碳酸岩在矿物组合上具有差别明显,含稀土矿物主要为磷钇矿、独居石和氟碳铈镧矿,稀土元素以轻稀土为主,但重稀土相对偏高,并具有以华阳川为中心向外围逐渐富集重稀土的特点。伟晶岩型稀土矿含矿主岩为含褐帘石伟晶岩,含稀土矿物为褐帘石,稀土元素以轻稀土为主。2类稀土矿化在形成时间上存在较大差异,碳酸岩型稀土矿化形成于印支期,伟晶岩型稀土矿化形成于古元古代晚期。区内已发现了众多的稀土矿床(点),成矿远景较好,特别是碳酸岩型稀土矿床(点)及碳酸岩脉带展布地段具有较大的找矿潜力。     

含油气盆地微观裂缝脉体期次、成因与流体演化研究进展及展望

沉积岩石中断裂与裂缝是含油气盆地流体活动的重要通道,断裂与裂缝中充填的不同期次、不同类型的矿物脉体是烃-水-岩相互作用的产物,记录了断裂、裂缝形成过程中不同期次流体性质、组分、来源以及温压场、氧化还原环境等信息,为研究沉积盆地断裂发育、流体动力场特征、物理化学环境及封闭与保存条件等地层古流体活动、动态演化过程提供了重要线索。系统总结了含油气盆地微观裂缝脉体流体活动示踪、演化的基本方法及其地质应用现状,认为目前主要集中在三个方面:(1)通过对裂缝脉体充填的成岩矿物岩石学观察,分析成岩矿物类型、结构及形成的相对次序;(2)通过对脉体成岩矿物的同位素、微量-稀土元素、流体包裹体等地球化学测试,示踪成脉古流体性质、来源、温压-氧化还原环境等;(3)通过对脉体成岩矿物放射性同位素(如U-Pb、Re-Os等)的测试,精确确定脉体形成时间,结合区域构造演化探讨脉体形成过程、流体动力场环境及其动态演化过程。最后分析了现有研究方法存在的问题,探讨今后的发展趋势及地质应用前景,以期为含油气盆地古流体演化及其与油气运移、聚集与保存等油气成藏机理的研究提供参考。     

山西义兴寨金矿流体包裹体的特征及意义

对山西省义兴寨金矿的流体包裹体进行了详细研究,测试样品为本区的花岗岩、花岗斑岩、多金属硫化物含金石英脉、黄铁矿含金石英脉、片麻岩和伟晶岩6种。研究发现有四个类型的流体包裹体:Ⅰ₁,富液相气液包裹体、Ⅰ₂富气相气液包裹体、Ⅱ含CO₂包裹体和Ⅱ含NaCl子晶多相包裹体。在矿石样品中可见到沸腾包裹体群发育,沸腾机制是热液运移时遇到火山通道及断裂而产生的压力下降。含矿石英脉的包裹体与次火山岩脉的包裹体特征十分相似,说明二者的热液具同源性。     

湖南溆浦县曾家溪钨矿地质特征及成矿地质条件

曾家溪钨矿位于湘西雪峰弧形构造成矿带中段,NE向区域性马家溪与枇杷湾2条斜冲断层所挟持的断块内,容矿地层为寒武系下统小烟溪组黑色岩系中。区内矿脉大多为隐伏—半隐伏的盲脉,地表矿化蚀变微弱,深部逐渐由不规则的石英脉和石英团块变为较规则的石英脉带或归并为单脉,矿床属受断裂破碎带控制的脉带型钨矿。初步勘查表明,含矿断裂破碎带向深部有较大的延伸趋势,矿区深部具有较好的找矿前景。     

江西发现一种新成因类型的三水铝石

郑秀中、葛金荣两同志在研究江西414含钽、铌钠长石化花岗岩风化壳中的粘土矿物的过程中,于强钠长石化、锂云母化花岗岩风化壳中发现大量可供矿山综合利用的三水铝石,其最高含量达24％,Al_2O_2/SiO_2为0.59,若对样品稍加处理,其含量可提高到60％以上,Al_2O_3/SiO_2达2.09。     

河南小秦岭石英脉型金矿床工业矿体构造定位规律及其机制

河南小秦岭地区广泛发育含金石脉型金矿床,主要工业脉依产状分为近东西向南倾及近南北向东倾两组,脉内工业矿体构造定位规律明显。研究表明,近东西向矿脉内工业矿体平面上主要产于控矿断裂走向东西方向段,剖面上产于断裂倾角较部位,在三维空间范围内工业矿体总体具向不仙太展布规律;而近南北向矿脉内工业矿体主要爱断裂走向变化影响,平面上多产于断裂走向段,且在三维空间范围无明显侧伏现象。了后结合控矿断裂产状,空间形态     

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