黄铁矿的一般特征与含金性的关系探讨

通过全面考察研究黄铁矿的一般矿物学特征与含金性的关系得知，第二和第三世代的黄铁矿是金矿化主期的形成物，与黄铁矿共生的矿物组合可作为金矿化的找矿标志和评价准则。黄铁矿的形态粒度与其含金性之间存在着显著的关系，即｛２１０｝晶形和｛１００｝＋｛２１０｝晶形的黄铁矿越多，自形程度越差，晶粒越细、越破碎，含金性就越好；反之亦然。成分研究分析表明，本区黄铁矿富Ｓ贫Ｆｅ，多Ａｓ多Ｃｏ，Ｃｏ／Ｎｉ平均为２．５３，Ｓ／Ｓｅ平均为１０８０４，显示内生热液矿床特征。Ｒ聚类分析和逐步回归分析表明，Ａｎ与Ｓ、Ｆｅ、Ｎｉ、Ａｓ关系密切。     

湖南铲子坪金矿的矿物标型及其地质意义

矿床位于白马山花岗岩外接触带附近，成矿阶段单一，矿物组份较复杂．金矿物颗粒细小，杂质少，成色高，硬度较高，与硫化物密切共生．石英以充填于构造空间的乳白色石英和交代构造岩的烟灰色、灰白色石英两种形式产出．二者同期共生，普遍发生塑性变形，含大量气液包裹体，气相成分以Ｈ２Ｏ和ＣＯ２为主，Ｈ２Ｏ＞＞ＣＯ２，贫Ｎ２，包裹体水的δ１８ＯＨ２ｏ比白马山花岗岩稍低．黄铁矿重结晶和动力变质现象普遍．五角十二面体、八面体黄铁矿的含金性好，立方体的含金性则较差．向深部，立方体黄铁矿减少，五角十二面体及其与立方体的聚形增多．黄铁矿的化学成分复杂，Ｓ／Ｆｅ＝１．９２—２．０２，亏硫；Ｃｏ／Ｎｉ平均为１．１７；Ｓｅ／Ｔｅ＝１２．４；Ｓ／Ｓｅ＝７．８×１０４；δ３４Ｓ分布于＋０．３２‰－７．５８‰的狭窄范围内．其晶胞参数（ａ０）与Ｃｏ、Ｎｉ、Ａｓ、Ｈｇ、Ｓｎ等质元素的含量相关．本矿床与胶东夏甸金矿类似，具有中－浅成中－低温岩浆热浪成因特点．成矿热浪来自白马山花岗岩，矿液由北向南，自西向东迁移．具大型矿床规模．矿床西部和Ⅰ矿脉带的深部有较好的找矿前景．     

黄铁矿的穆斯堡尔谱特征及其机理分析

本区金矿中黄铁矿的Ｍｏ谱测试和综合分析表明，主要穆斯堡尔参数的变化与含金性之间存在有一定的关系。主要表现为，黄铁矿的Ｉ．Ｓ．值与含金性间呈明显的负相关。Ｏ．Ｓ．值与含金性间则呈明显的正相关，且Ｏ．Ｓ．值随着（Ａｕ＋Ａｓ）／（Ｃｏ＋Ｎｉ）原子数比值的增大而增大。这是由于Ａｕ＋取代Ｆｅ２＋进入黄铁矿晶格使其结构产生畸变所致。置换时电荷补偿可通过两个途径来实现，其一是Ａｕ＋（Ｃｏ３＋、Ｎｉ３＋）→２Ｆｅ２＋，其二是Ａｓ３＋＋Ａｕ＋→２Ｆｅ２＋。     

作物产量与土壤环境的关系

作物的产量与土壤元素中Ｎ、Ｐ、Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｓ、Ｆｅ、Ｍｎ、Ｃｕ、Ｚｎ、Ｂ、Ｍｏ、Ｖ、Ｃｏ、Ｎｉ、Ｃｒ、Ｐｂ、Ｃｄ、Ｈｇ、Ｓｅ、Ｆ、ＴＩ、Ｂａ、Ｔｅ、Ｔａ、Ｓｒ、Ｔｉ、Ｓｉ等元素及稀土、有机质、酸碱度和含水量、含盐量密切有关。     

陕西东沟坝金银矿床黄铁矿标型性研究

陕西东沟坝金矿床黄铁矿成分亏硫，低Ｃｏ，Ｃｏ／Ｎｉ＜０．５，晶形以ａ，ａｅ和ａｅｏ聚形为主，热电性以ｎ，ｐｎ型为主，矿床四维上的特征表明其具复成因标，通过研究，总结出黄铁矿的矿化标志：硫亏损少，热电系数为常见值，且离散极差大，形态系数在１４～－１５２之间。     

烧锅营子金矿黄铁矿的化学成分标型特征

烧锅营子金矿床的黄铁矿形成于早，中，晚３期，是主要的矿石矿物和载金矿物，其中以中期黄铁矿为最主要的载金者。黄铁矿的化学成分为；ＴＦｅ４３．３４％－４５．５２％，Ｓ４６．５８％－４８．８６％，，与标准黄铁矿相比显示亏铁，亏硫特点，黄铁矿为含丰富的微量元素，有Ａｕ，Ａｇ，Ａｓ，Ｓｂ，Ｂｉ，Ｃｕ，Ｚｎ，Ｐｂ，Ｃｏ，Ｎｉ，Ｗ，Ｍｏ，Ｓｅ等。其中Ａｕ，Ａｇ，Ｃｕ，Ｐｂ，Ｚｎ，Ｂｉ含量较高，而Ａｓ，Ｓｂ低，Ｓ     

朝阳小塔子沟金矿床中黄铁矿的标型特征

本文从黄铁矿形态、成分和熟电性等方面研究了小塔子沟金矿床黄铁矿的标型特征。得出小塔子沟金矿中富矿（矿体）黄铁矿标型特征是：晶体形态复杂且种类多，以立方体、五角十二面体或其聚形晶为主：高Ａｓ，低Ｃｏ，Ｎｉ，Ａｓ／（Ｃｏ＋Ｎｉ）〉１．５；导电类型４种都有且以Ｐ型和Ｎ－Ｐ型为主，Ｖｎｐ〉－１０ｍｖ，α〉－９０μｖ／℃。贫矿（围岩）黄铁矿的标型是：晶形单一为立方体；低Ａｓ；高Ｃｏ，Ｎｉ值；Ａｓ／（Ｃｏ＋Ｎ     

萨拉林斯克金矿床中黄铁矿的结构和化学不均一性

萨拉林斯克金矿床的矿石属石英－硫化物型。黄铁矿中Ｎｉ、Ｃｏ、Ａｓ、Ａｇ和Ａｕ的含量范围很宽。它们的含量与Ｓ／Ｆｅ值呈规律性变化，说明它们以类质同象形式进入矿物结构中。查明了矿石含金性与黄铁矿成分的关系，并建立了矿体的结构模式。     

半宽金矿床微量元素的地球化学研究

半宽金矿床有两类矿石：石英－黄铁矿型和石英－多金属硫化物型。微量元素研究表明元素组合为Ｂｉ，Ｐｂ，Ａｕ，Ａｇ，Ｚｎ，Ｓｂ，Ｗ，Ｃｕ，Ａｓ，Ｍｏ。矿石中铅含量是区分黄铁矿型矿石和多金属硫化物矿石的重要指标。金矿化与Ｃｏ／Ｎｉ，ＣｕＰｂ，Ｒｂ／Ｓｒ值密切相关。     

胶东西北部仓上金矿床上盘围岩蚀变和黄铁矿标型特征研究

上盘围岩是矿床钻探过程中首先遇到的围岩,研究其蚀变特征具有重要的找矿指导意义。对胶东西北部露天开采的仓上金矿床的详细研究表明,上盘围岩蚀变以绿泥石化为主,蚀变分带自远矿端到近矿端依次为方解石绿泥石化带、赤铁矿绿泥石化带、绿帘石化带和绢英岩化带。黄铁矿的形态、成分和热电性标型显示,成矿过程中上盘围岩提供了丰富的Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ、Ｐｂ、Ｚｎ和Ａｕ、Ｐｔ等。上盘围岩的近矿标志是绢英岩化增强,黄铁矿的｛１００｝＋｛２１０｝增多,Ｓ、Ｃｕ、Ｐｂ、Ｚｎ和Ａｕ、Ｐｔ增高,Ｓ／Ｆｅ离子比和ｗ（Ｃｏ＋Ｎｉ）／ｗ（Ａｓ＋Ｓｂ）降低,Ｐ型黄铁矿出现率增高,蚀变岩的金含量增高。     

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.     

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.)