河南萑香洼金矿地球化学分带模型研究

河南萑香洼金矿床作为典型的构造蚀变岩型金矿床,通过研究分析该矿床F985矿化带的Ⅰ号矿体各类元素组分在不同地质体的含量变化特征,原生晕异常分带特征和地球化学轴向分带特征,建立了该矿床完整的地球化学异常分带理想模型,得出矿床地球化学异常轴向分带序列确定为:烃类、Sb(前缘晕)→As、Hg(矿头)→(矿中晕)Au、Ag、Cu、Pb、Zn、W、Mn→(矿尾晕)Mo、Co、Ni、Sn,并总结出了找矿预测标志,为该矿区深部找矿提供了一定的科学理论依据。     

新疆石英滩金矿床原生晕特征与隐伏矿预测

通过对新疆东天山石英滩金矿床L4矿体各开采中段及钻孔的岩石系统采样分析和计算统计,确定了该金矿床的地球化学原生晕指示元素的组合特征、轴向分带、横向分带和纵向分带.结合国内外对该类型金矿原生晕地球化学特征和分带性研究成果,建立了本区该类型金矿床轴向分带的理想模型,预测深部隐伏矿体的可能位置,为本区寻找和勘察隐伏金矿提供了较为可靠的地球化学依据.     

吉林荒沟山金矿床地球化学找矿模型

以荒沟山金矿床的成矿地质特征为基础，研究了区域地球化学及异常特征，矿床地表及深部地球化学异常特征和原生异常元素分带性规律。初步总结出寻找该类型矿床的若干地球化学及异常指标，建立了地球化学找矿模型。     

河南瑶沟金矿矿床地球化学特征及成矿预测模型

瑶沟金矿床地球化学特征研究表明，主成矿因子为中偏高温元素组合，成矿与岩浆热动力活动有关，矿床元素垂直分带显示深部可能有盲矿体存在，水平分带表明成矿元素在热液中的运移方向为由西向东，矿体剥蚀程度为中－下部，其地球化学原生晕剥蚀程度为中－上部。据上述特征建立了矿床地球化学预测模型 。     

钟丘洋火山热液型铜矿床地球化学异常特征

据钟丘洋火山热液型铜矿床的地层、侵入岩、矿石和矿体中元素的分布规律,阐明了该矿床的地球化学原生异常特征;确定了与矿床有关的指示元素及其分带序列;建立了矿床剥蚀程度的评价指标及该矿床的地球化学异常模式。     

安徽庐江黄屯铜金矿床原生晕特征及矿床成因

通过对安徽庐江黄屯铜金矿床18号勘探线上的4个钻孔岩心进行系统取样和分析,研究了18号勘探线剖面地质特征及原生晕分带特征,探讨了该矿床的地球化学异常模式及矿床成因。黄屯铜金矿床的特征元素组合为Au、Ag、Cu、As、Sb、Bi、W,原生晕垂向分带序列为（Sb、As）-（Ag、Au、Cu）-（Bi、W）。18号勘探线剖面地质特征和原生晕形态特征显示,在ZK18-1钻孔和ZK18-2钻孔之间可能存在隐伏断层,造成铜金矿体和地层错动。在TK02钻孔底部发育热液矿床前缘晕元素组合异常,指示深部可能存在隐伏矿体。综合研究认为,黄屯铜金矿床的成矿物质可能主要来源于火山热液和闪长玢岩,该矿床为火山-次火山热液型矿床。     

青海赛坝沟金矿床Ⅳ-3号矿体原生晕特征与深部预测

对赛坝沟金矿床Ⅳ-3号矿体原生晕元素进行理论性分析后得到原生晕轴向分带特征,其前缘晕、近矿晕、尾晕分布混杂,呈现出明显的逆向分带特征,其中轴向分带序列最后出现的Au和Ni呈现良好的相关性以及前缘元素Hg的出现,指示矿体向下的延伸空间较大。进一步对其轴向地球化学参数进行对比,矿体由浅至深,地球化学参数具有"升—降—升"的变化特征,显示矿体在3 162 m中段往下还有很大的延伸性。通过对该矿体原生晕轴向分带序列及地球化学参数的研究对比,建立矿体的叠加晕理想模型,为矿区深部及其周边小型矿床的评价预测提供地球化学依据。     

佛子冲铅锌矿田矿床地球化学异常特征及找矿模式

本文通过研究佛子冲铅锌矿田中两个典型矿床剖面的地球化学特征,分析其原生晕发育特征及垂直分带特征和次生晕发育特征及水平分带特征。总结归纳了异常元素的组合、强度、规模、分布及与矿体的关系等特征。并在此基础上建立了矿床的地球化学找矿模式。     

贵州泥堡金矿床原生晕特征及深部找矿预测——以Ⅲ-1号矿体为例

为预测和评价贵州普安泥堡金矿床的成矿潜力,采用原生晕地球化学方法对10460勘探线所控制的Ⅲ-1号矿体进行原生晕轴向分带特征研究。采集了该勘探线上6个钻孔矿体附近的构造蚀变岩石样品进行ICP-AES分析。通过对各元素进行相关性分析及因子分析,选取原生晕地球化学特征研究的指示元素为Au、As、Ag、Cu、Hg、Mo、Co、Cd、Sb。综合原生晕分带图及指示元素分带序列分析,判断Ⅲ-1矿体原生晕出现了明显的分带异常,其由浅部到深部总体表现为:前缘晕元素+尾晕元素—近矿晕—前缘晕元素+近矿晕元素+尾晕元素的元素异常分布序列,指示在深部存在一个或多个隐伏矿体,是造成元素异常叠加共存与轴向分带序列异常的原因。     

广西贵港六梅金矿原生晕及深部找矿

六梅金矿床位于广西贵港市龙山矿田福六岭金矿区,属于卡林型金矿床,矿体呈脉状分布。对矿山已开采中段系统采样,进行原生晕研究。矿床元素的空间分布规律显示六梅金矿床中Au、As为正相关关系,含量等值线在空间上吻合性良好,As可作为Au找矿的主要指示元素。原生晕轴向垂直分带序列自上而下为:Cu-Zn-Pb-Hg-Mo-W-Au-As-Ag-Bi-Sb,为"反分带"序列,显示出该金矿床具有多期次多阶段叠加成矿成晕的特点。根据矿床原生晕地球化学特征预测深部矿化的存在。     

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