云南镇康地区区域地球化学特征及找矿方向

基于1∶5万水系沉积物测量成果,对云南镇康地区的地球化学参数进行计算和分析,并对分布特征、岩石地球化学特征、异常元素组合特征进行研究。结果表明,二叠系沙子坡组(Ps^)中的Cu、Ni、Hg、Mo、Zn、As含量高出全国水系沉积物均值的2~4倍,是该区最具找矿潜力的地球化学地层。以Zn、Pb、Cu为主的异常元素组合主要分布在芦子园复式背斜轴部附近;而以Hg、Sb、Pb为主的异常元素组合主要分布在麻栗林断裂以东的大东子—南伞隆起部位,异常呈北东或北北东向展布,与主要构造线方向一致。研究区元素异常分带与区内已知矿产一致,具有由南往北,由Cu、Pb、Zn、Ag、Mo、W、Ni等逐渐向Pb、Zn、Ag、As、Au、Sb、Hg→Sb、Hg的元素温度分带特征,应按此元素分带规律寻找相应矿产。结合地质、矿产分布特征,圈定了找矿靶区9个,为该区寻找多金属矿提供地球化学依据。     

澜沧老厂外围银铅锌铜多金属异常资源潜力评价

基于澜沧地区1：10万分散流普查结果，利用澜沧老厂地球化学异常成矿模型，确定该区地球化学异常中Pb、Zn、Ag、Cu的成矿率。根据其它地球化学异常中蕴古Pb、Zn、Ag、Cu等元素的所有金属量，对异常所含Pb、Zn、Ag、Cu资源量作出初略评价。     

黑龙江省新林-塔源地区地球化学特征及成矿远景预测

通过对黑龙江省新林-塔源地区1∶5万水系沉积物测量数据的统计分析,结合多学科知识,对研究区Au、Ag、As、Sb、Bi、Cu、Pb、Zn、Mo、W、Cr、Ni、Hg 13种元素的平均值、标准离差、变异系数、相关性和元素空间分布情况等各项地球化学参数特征进行因子分析及聚类分析,总结出各元素的地球化学分布特征及地质意义。通过对研究区典型矿床的综合研究,总结出区域成矿地质和地球化学条件,结合单元素异常和组合异常的解释评价,最终认为矿集区北部有找到表生铅锌多金属矿的可能,而南部是寻找隐伏铅锌多金属矿的有利地段。     

云南北衙地区成矿地球化学特征及找矿方向

利用北衙整装勘查区1∶20万水系沉积物地球化学数据,综合分析了地层、岩浆岩、典型矿床主要成矿元素Ag、Au、Cu、Pb、Zn的富集规律,对元素分布特征、综合异常特征、相关性及异常元素组合特征进行初步研究,确定了找矿有利指标组合;通过对比北衙金矿区典型矿床成矿地质、地球化学特征,结合地层、岩浆岩等找矿标志预测北衙地区的找矿远景区。结果表明:综合区域上的地层、构造、岩浆岩和区域矿产等资料,对成矿元素异常组合进行地球化学分区是可行的,能有效反映致矿异常,突出矿化信息;根据区域单元素Au、Ag、Pb、Zn、Cu地球化学特征以及组合元素异常特征结合成矿地质背景,指出了炭窑金矿、铅锌矿找矿靶区;马鞍山北部金矿找矿靶区,为北衙整装勘查区外围找矿提供了指导作用。     

冀北上黄旗地区水系沉积物地球化学背景特征与找矿远景

在1∶50 000水系沉积物测量的基础上,从元素地球化学参数特征、不同地质单元中元素分布特征、元素地球化学场分布等方面对上黄旗地区地球化学背景特征进行了探讨,指出区内Ag、Pb、Zn、Au、Mo后期叠加富集特征明显,是本区今后勘查找矿工作的主攻矿种;古元古代变质地层和变质侵入岩中Pb、Zn、Ag等元素富集且含量变异系数大,是铅、锌、银多金属矿的潜在矿源层;圈定了闯王沟门铅、锌、银、钼等多金属矿找矿远景区6处。     

河南汝阳王坪西沟铅锌矿床地球化学特征

通过对河南汝阳王坪西沟大型铅锌矿床地球化学特征的分析研究，揭示了利用土壤化探作为有效手段，发现并查明铅锌矿床的基本思路。同时证实，土壤化探在铅锌找矿方面效果是好的。通常，主要工业铅锌矿体均限制在Pb、Zn、Ag、Cu组合异常的外边缘以内，而且其成矿母岩等主成矿元素Pb、Zn只要大于涂和费及维诺格拉多夫值有关中性岩Pb含量2．5倍、Zn丰度值2倍以上，均可列入与找矿有利的原生晕异常。     

青海省尕河地区水系沉积物测量异常特征及优选找矿靶区

通过对尕河地区1∶2.5万水系沉积物资料处理,圈定了Cu、Pb、Zn、Ag、Au、As、Sb、Cr、Ni、Co等异常,揭示了区内异常的分布特征,评价异常的找矿意义,划分了元素组合,结合地质成矿背景,依据化探综合异常及中低温热液型元素组合特征,确定Pb、Ni、Ti的4个找矿远景区,其中优选出3号铅找矿靶区,4号钛、镍重点找矿靶区。     

冀北西龙头-半截塔地区地球化学特征与找矿远景区浅析

本文以1/5万水系沉积物测量成果为基础,从地球化学参数特征、元素组合特征、区域分布规律和异常特征等方面对西龙头-半截塔地区地球化学背景进行了分析,认为该区主要成矿元素异常受NE向构造、岩浆岩控制明显,主要成矿元素Ag、Pb、Zn、Mo等异常发育,强度高、浓度分带比较清晰,是寻找中低温热液型银铅锌多金属矿床的有利区域。结合地质、化探综合信息,在该区圈定了5处找矿远景区,可为进一步矿产勘查工作提供参考。     

胶东牟平—文登地区地球化学特征和金成矿潜力:基于1:5万水系沉积物测量

为了研究成矿元素地球化学异常,在山东胶东牟平—文登地区,开展了-60目粒级的1∶5万水系沉积物测量,对水系沉积物中元素含量分布、综合异常特征、相关性及异常元素组合特征进行了研究,在研究区圈定综合异常72处,结果发现:研究区内Au、Ag、Cu、Pb、Zn、Mo的异常规模大,异常多分布在断裂构造中,地质及地球化学条件优越,具有较大的成矿潜力,结合区域构造成矿特征揭示水系沉积物和主要地质体中地球化学异常分布及其成因联系。依据综合异常特征和地质信息圈定3处找矿远景区。初村王家泊子和汤村店子金找矿远景区是寻找石英脉型、破碎带型金矿的有利地段,构造发育,且有多期次活动特征,地表可见褐铁矿化、硅化等,异常元素元素组合齐全、强度高、浓集中心明显;解家庄金铅找矿远景区。     

江苏新沂高流地区土壤地球化学特征及找矿预测

在总结江苏新沂高流地区地质特征的基础上,结合区内1∶10 000土壤地球化学调查工作,系统研究该区元素含量及组合特征,并进行找矿预测。异常结果显示该区Au、Ag、Cu、Mo、Pb、Zn、As、Sn等单元素地球化学异常明显,其中Au、Ag、Mo 3个元素的异常强度和分带性均好,其形态分布受NNE向构造破碎和碱长花岗岩体等因素制约。在研究区共圈定了14处综合异常,通过异常评价,位于同一断裂带附近的3处异常成矿地质条件优越;对综合异常开展地球化学剖面查证工作,结果显示其中1处Au、Cu等元素峰值均位于NNE向断裂带中心位置。结合该区成矿地质条件和土壤地球化学异常特征,初步总结了研究区金、多金属矿找矿标志,为该区进一步找矿提供间接依据。     

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