青海省都兰小卧龙锡、铁、钨多金属矿地质特征及找矿标志

小卧龙锡铁钨多金属矿床产于下古生界奥陶-志留系滩涧山群与酸性侵入岩之间的矽卡岩接触带中,含矿矽卡岩带总体呈NE向展布。矿床由38条铁矿体和29条锡多金属矿体组成。锡铁钨多金属矿可划分为矽卡岩期、石英-硫化物和表生期三个成矿期。矿体具有上铁下锡,东铁西锡的分布特征。根据矿床特征和矿体的空间分布规律预测深部岩体锡多金属矿的找矿前景良好,围岩中注意寻找云英岩型和石英脉型锡多金属矿。     

广西西大明山弄屯铅锌矿床成矿地质特征及找矿前景

弄屯铅锌矿床位于广西西大明山钨-铋-铅-锌-银多金属矿集区北西部。矿床产于寒武系与泥盆系角度不整合面附近地层层间构造破碎带内,为中低温热液充填型矿床。初步发现5条铅锌矿带,圈定144个矿体。矿体走向主要为 NE—SW 向,倾向 SE,倾角相对较陡。矿体形态多呈脉状、似层状或透镜状。厚度、品位变化较稳定,主要为硫化铅锌矿石类型,具有矿石利用性能好等特点。控矿构造主要有NE 向及近 EW 向断裂。其矿床规模较大,具有较好的找矿前景。     

湖南大义山锡多金属矿田矿体分布规律、控矿因素及找矿方向

通过对大义山锡多金属矿田基本地质特征和成矿规律的综合研究,查明锡多金属矿化主要产于大义山花岗岩体的内外接触带中,阐述了矿体分布与定位规律,分析了赋锡多金属矿花岗岩特征、断裂构造、褶皱和岩体构造对矿体形成、演化与就位的制约关系.认为成矿作用主要与中侏罗世-晚侏罗世的花岗质岩浆活动相关,并探讨了大义山岩体和锡多金属矿成岩成矿机制及该锡多金属矿的找矿方向.     

六盘水煤田黑塘煤矿构造特征及其演化

通过系统分析六盘水煤田黑塘煤矿地质构造特征及演化认为:黑塘煤矿向斜构造—龙家沟向斜,轴向南东-北北东向,浅部地层倾角25°~50°,深部5°~20°;矿井内断层总体走向NE,倾向多为SE,断层落差多小于50 m,且正断层数量多于逆断层;断层组合样式多样;矿井构造的形成及演化受区域构造控制明显,燕山中期研究区经历了NE-SE向挤压、近NS向挤压和NW-SE向挤压的应力转换过程,奠定了研究区NE向的主体构造格局;燕山晚期NW-SE向拉张作用,使断裂构造性质发生转变,导致矿井现今正断层为主导。     

邹家山铀矿床矿体形态、规模及其变化特征

邹家山铀矿床位于相山火山-侵入杂岩体西部,产于早白垩世碎斑熔岩和流纹英安斑岩中。勘查报告显示,矿体受NE向断裂、裂隙控制,矿体形态简单,呈脉状、透镜状,成群、成带,产状单一,倾向NW,倾角40°~60°。但开采资料表明,矿体形态复杂,有脉状、透镜状,也有囊状、折线型、弧型、Y字型、人字型和树杈状等。在空间分布上,北东端矿体走向大多为NE向,倾向NW;往南西方向,矿体产状变得较复杂,有的矿体呈近EW走向,倾向S,有的呈NW走向,倾向SW,还有的呈SN走向,倾角较大;到了47线以南,矿体走向多为NW向,倾向SW。同时还发现,许多矿体明显偏小,现有的钻探间距难以对其形态和规模准确控制。     

淄博市瓦泉寨矿区铁矿床地质特征及其成因

沉积变质型铁矿是山东省鲁西地区重要成因类型之一,含矿层位为新太古代泰山岩群。经过地表工程和钻探工程验证,瓦泉寨矿区C1、C2、C3、C5磁异常是由铁矿体引起。矿体总体走向NW,倾向NE,倾角55°~88°,厚度1.44~6.29m;主要矿物为磁铁矿;矿石主要呈粒状变晶结构、条带状构造。同时,本文对沉积变质型铁矿床的成因进行了分析,铁质来源与基性火山活动关系密切。     

江西遂川草林金矿床地质特征及找矿标志

草林金矿属石英脉型金矿床。矿床(体)赋存于加里东期花岗闪长岩体内外接触带中,沿NW向横店复向斜两翼分布。金矿化与岩石中发育的NW向蚀变破碎带石英脉关系密切,矿体成组成群分布,矿体长度20~70m,厚0.12~1.39m。金成矿年龄测定为燕山期。矿体富集与多金属硫化物复脉充填和NE向、EW向裂隙构造复合处有关。矿体富集于氧化-还原界面附近。地球化学异常和蚀变破碎带石英脉是主要找矿标志。     

山东七宝山多金属矿区敞沟矿段Ⅰ号脉铅锌矿化赋集规律研究

敞沟矿段位于山东五莲七宝山多金属矿区矿区中南部,共由10条多金属矿脉组成,产于次火山岩体内侧,其中以Ⅰ号铅锌矿体规模最为大,矿体主要延伸方向为近东西,倾向南西,倾角变化较大,35°~80°不等。采用OPIS软件,对控矿构造及矿石品位等的主要矿化指标进行趋势预测与分析,通过各个矿化指标的等值线图分析结果表明,对Ⅰ号铅锌矿体矿化富集规律进行简要描述,结合矿体形态变化,最终得出两个可能的找矿区域,G710线中浅部,标高约-50~180 m区域,G707线中深部,标高约-150~-290 m区域。     

湘东南锡田辉钼矿Re-Os同位素定年及其地质意义

湘东南锡田是近年来新发现的一个具有大型规模的钨锡多金属矿田,该矿田位于湘赣边界,南岭成矿带与钦杭成矿带的交汇部位,扬子地块与华夏地块的拼合带。目前对于矿体与成矿岩体之间的关系以及矿体形成时代的问题尚存争议,钨锡矿化究竟是与印支期还是与燕山期花岗岩有关,矿田中众多矿体是否同期形成,这些问题仍待进一步确定。本文选取了两个矿床,即山田云英岩-石英脉型锡多金属矿床和桐木山破碎带蚀变岩型锡多金属矿床,分别对来自这两个矿床的辉钼矿样品进行了Re-Os同位素定年,获得的ReOs模式年龄分别为(158.9±2.2)Ma(2SD)和(160.2±3.2)Ma(2SD),表明这两个矿床形成于晚侏罗世早期。高精度的云母Ar-Ar和辉钼矿Re-Os年龄数据表明锡田钨锡多金属矿田的垄上、荷树下、山田、桐木山矿床均形成于150~160 Ma,即南岭与花岗岩有关钨锡多金属矿大规模成矿作用的高峰期。上述两个辉钼矿样品的铼含量分别为12.44×10-6和2.367×10-6,指示成矿物质分别为壳-幔混合来源和地壳来源,为准确认识该矿田的成矿物质来源提供了进一步的制约。本文还对南岭地区晚侏罗世与花岗岩有关的钨锡多金属矿中90个辉钼矿的铼含量数据进行了统计,结果表明钨锡多金属矿的成矿物质绝大多数为地壳来源,少数为壳-幔混合来源。     

六盘水煤田黑塘煤矿构造特征及其演化

通过系统分析六盘水煤田黑塘煤矿地质构造特征及演化认为:黑塘煤矿向斜构造—龙家沟向斜,轴向南东-北北东向,浅部地层倾角25°⁵0°,深部5°50°,深部5°²0°;矿井内断层总体走向NE,倾向多为SE,断层落差多小于50 m,且正断层数量多于逆断层;断层组合样式多样;矿井构造的形成及演化受区域构造控制明显,燕山中期研究区经历了NE-SE向挤压、近NS向挤压和NW-SE向挤压的应力转换过程,奠定了研究区NE向的主体构造格局;燕山晚期NW-SE向拉张作用,使断裂构造性质发生转变,导致矿井现今正断层为主导。     

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).     

NONMETALS DEPOSITS

正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)     

MATHEMATICAL GEOLOGY

正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,     

PROSPECTING EXPLORATION

正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)     

STRUCTURAL GEOLOGY

正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-     

STRUCTURAL GEOLOGY

正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with