安徽沙溪斑岩铜矿床中伴生金的赋存状态

矿体赋存于燕山早期形成的石英闪长斑岩及闪长玢岩中。矿石的主要金属矿物有:黄铜矿、黄铁矿、斑铜矿、自然金、银金矿等。黄铁矿、黄铜矿是金的主要载体矿物。通过矿相鉴定、单矿物化学研究、物相分析,电子探针分析、透射电镜分析等,查明了金的赋存状态。显微金呈包体状态包含于黄铜矿之中,粒径为5—20微米。次显微佥呈球状、链状及不规则状分布于黄铁矿晶体边缘及微裂隙中。经探针分析,金的成色为790—850,平均成色为815。经物相分析,金的矿物量为85%—95%,表明金是以矿物态存在。我国玉龙、德兴、多宝山等地的斑岩铜矿都有不同程度金的显示,查明金的富集规律及赋存状态,对于综合开发斑岩铜矿,提高矿床利用价值将会开拓新的前景。     

山东省平度市大庄子金矿区黄铁矿、方铅矿与金的共生关系研究

通过对山东省平度市大庄子金矿区黄铁矿、方铅矿三个蚀变阶段特征研究,发现金矿化主要发生在第二阶段,强烈的石英-黄铁矿-碳酸盐化与金矿化的关系最为密切。金多数以包体的形式赋存于黄铁矿等金属硫化物中,并且在黄铁矿、方铅矿、闪锌矿等矿物共同产出时更有利于金的富集。研究认为石英和黄铁矿组合以及黄铁矿、黄铜矿、方铅矿、闪锌矿的组合可作为金的富集指示性矿物组合,伴生矿物之中方铅矿含金性最好。方铅矿、黄铜矿、闪锌矿和磁黄铁矿呈细脉状、网脉状、斑杂状产于含金石英脉和团块状黄铁矿的裂隙中,研究发现细脉状较团块状黄铁矿含金性要好。     

胶东玲珑金矿田金的赋存状态及其对成矿过程的指示意义

胶东地区是我国最大的黄金基地,探明黄金资源储量超过5000t。胶东地区金矿床主要发育两种矿化样式,即浸染状细脉-网脉型矿化和石英-硫化物脉型矿化,金主要以可见金形式赋存于黄铁矿和石英中。玲珑金矿田位于招平断裂带北端,同时发育两种矿化样式的矿体,是研究金赋存状态的理想选区,理清金的赋存状态对于选择合适的选冶工艺以及揭示金的成矿作用和富集机制具有重要的研究意义。在详实的野外地质调查基础上,通过显微岩相学观察、电子探针分析与矿物自动定量分析,对胶东玲珑金矿田两种不同矿化样式的样品中可见金的赋存状态进行了对比研究,探讨了金成矿过程。玲珑金矿田两种矿化样式矿石中金矿物的赋存状态并无显著差异,金矿物主要为银金矿和自然金。嵌布状态为裂隙金、包体金、粒间金,以粒间金和包体金为主。金矿物粒度以微粒-细粒为主,石英脉中偶见中粒-粗粒金矿物。金矿物主要以独立矿物形式以及与黄铜矿、方铅矿等硫化物共生的形式赋存于黄铁矿中。石英-黄铁矿阶段金矿物成色高于石英-多金属硫化物阶段金矿物成色,主要是受到成矿温度的影响。浸染状细脉-网脉型样品金矿物比石英-硫化物脉型样品金矿物具有更高的金成色,是由于两种矿化样式沉淀机制差...     

利用电子探针研究甘肃陇南赵家庄金矿载金矿物特征

应用偏光显微镜与电子探针相结合的手段是研究载金矿物的主要方法。本文采用镜下鉴定和电子探针分析技术,对赵家庄金矿中载金矿物含量、形态特征及其与其他矿物的空间关系开展研究,并对载金矿物进行定性和定量分析,探寻具有找矿意义的载金矿物和总结标志矿物特征。结果表明:研究区金矿石中主要载金矿物为黄铁矿,少量为黄铜矿、闪锌矿,这些载金矿物中Au含量依次为:细晶黄铁矿粗晶黄铁矿草莓状黄铁矿黄铜矿。不同时期的黄铁矿(粗晶黄铁矿、细晶黄铁矿、草莓状黄铁矿)中Au的分布均匀,但存在差异性,主要表现为细晶黄铁矿和草莓状黄铁矿中的Au含量较高(平均含量0. 14%～0. 18%),这种现象表明此类矿物为构造热液期形成,金易富集。Au以两种形式存在,一种是"可见金"包裹于脉石矿物中,或以裂隙金的形式嵌布在矿物晶隙及裂隙中;另一种是"不可见金"以纳米级颗粒金的形式存在于载金矿物中,也是Au的主要存在形式。本研究为后期矿床的成因、成矿过程和成矿机理研究提供了佐证,同时易于根据含金矿物的特征选择合适的选冶方法。     

木里县梭罗沟金矿伴生有用组分调查评价

文章对梭罗沟金矿体和选矿厂进行系统全面取样,通过化学分析测试基本查明梭罗沟金矿伴生组分,矿体达到评价指标有S、As、Ag,其中伴生有害组分为S、As,伴生有用组分为Ag;选矿厂仅金精矿中Cu、Co、Ni达到评价指标,含量低且分散。通过光片鉴定和电子探针分析测试,伴生银以独立矿物(银)黝铜矿细粒包裹体的形式赋存于黄铁矿、毒砂中,多沿黄铁矿、毒砂矿物中的裂隙呈脉状产出或沿黄铁矿表面分布。在黄铁矿、黄铜矿等矿物中的赋存状态不明,推测可能以机械混入物、显微包体等形式产出。     

木里县梭罗沟金矿伴生有用组分调查评价

文章对梭罗沟金矿体和选矿厂进行系统全面取样,通过化学分析测试基本查明梭罗沟金矿伴生组分,矿体达到评价指标有S、As、Ag,其中伴生有害组分为S、As,伴生有用组分为Ag;选矿厂仅金精矿中Cu、Co、Ni达到评价指标,含量低且分散。通过光片鉴定和电子探针分析测试,伴生银以独立矿物(银)黝铜矿细粒包裹体的形式赋存于黄铁矿、毒砂中,多沿黄铁矿、毒砂矿物中的裂隙呈脉状产出或沿黄铁矿表面分布。在黄铁矿、黄铜矿等矿物中的赋存状态不明,推测可能以机械混入物、显微包体等形式产出。     

安徽白岭金矿金的赋存状态研究

白岭金矿位于下扬子台坳、长江褶断隆起带中段。金矿体赋存于三叠系中统铜头尖组中，矿体形态呈不规则脉状。矿石类型主要有以含金褐铁矿为主的氧化矿石和以含金黄铁矿为主的原生矿石两大类。载金矿物主要有黄铁矿、褐铁矿、石英、伊利石、黄铜矿等。通过矿相鉴定，单矿物含金分析、物相分析、多点分析、电子探针分析等，查明了金的赋存状态。金矿物以自然金为主，其次为银金矿。金的粒度较细，主要为中细粒显微金。金的嵌布类型有包体金、晶隙金、裂隙金。金的成色较高，平均为906．5。金主要呈矿物态存在。     

福建尤溪肖板金矿床金的赋存状态及金矿物特征

肖板金矿床属受构造控制的中低温岩浆热液矿床,矿化类型为构造蚀变岩型。金多呈独立金矿物形式出现,少许呈分散状;金矿物以自然金为主,平均成色９３０,有少量银金矿和碲金矿。金矿物以包体金、裂隙金、连生金和粒间金等形式嵌布于黄铁矿、黄铜矿、石英、方铅矿及方解石等主要载金矿物中,且石英、方解石中较金属硫化物中占优势。金矿物形态各异,粒度以中细粒为主。     

我国微细浸染型金矿某些载体矿物中金的赋存状态

本文研究了我国微细浸染型金矿中主要载体矿物的含金性,深入讨论了黄铁矿和水云母中金的赋存状态,确定了不同产状的同一矿物中金具有大不相同的赋存状态,主要有次显微金、类质同象金和胶体吸附金等三种状态。     

皖西南安庆月山铜(钼)矿床中金的赋存状态研究

应用光学显微镜、化学分析、电子探针和质子探针(PIXE)等多种分析研究方法,系统地研究了安庆月山铜(钼)矿区铜牛井矿床不同类型的铜矿石中金的赋存状态。研究结果表明,矿石中金呈显微自然金存在,它们分别是含银自然金、银金矿和纯金存在于石英脉型铜矿石、含铜方解石脉以及闪长岩型铜矿石中;主要载金矿物是黄铜矿、黄铁矿等矿物。研究结果为该矿区矿石中伴生金的综合利用提供了科学依据,同时也为同类矿床中金的赋存状态研究提供了新的方法。     

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