土屋-延东铜钼矿田与成矿有关问题的讨论

为查明新疆土屋-延东铜矿的围岩地层时代、成矿时代和成矿环境等问题，文章通过野外调查、岩矿鉴定、古生物化石鉴定和同位素年代学等方面的研究，提出围岩地层为石炭系而不是泥盆系；锆石SHRIMP定年结果表明334．6～320Ma为围岩火山岩的形成时代，另外还有两期岩浆活动(434～426Ma和260Ma)；含矿直接围岩主要是斜长花岗斑岩而不是闪长玢岩；矿田隶属觉罗塔格构造-成矿带而不是哈尔里克带；矿田内斑岩类以及矿带中的石炭纪花岗岩类具埃达克岩特征，表明区域上具良好的斑岩铜矿成矿远景。     

云南省施甸县摆田铅锌矿地质特征及找矿标志

云南施甸县摆田铅锌矿,矿体呈似层状、透镜状赋存于南北向断层构造破碎带中,断裂构造控矿明显。矿体含矿岩性为碳酸盐岩类,矿体顶板围岩为中三叠统河湾街组(T_2h)砂质白云岩、灰质白云岩、白云质灰岩,矿体底板围岩为上三叠统牛喝塘组(T_3nh)凝灰岩、凝灰质泥岩。断层构造、围岩蚀变和PbZn地球化学异常是直接的找矿标志。     

安徽池州马头矿区斑岩型钼矿含矿裂隙研究

通过对安徽池州马头矿区含矿裂隙的综合研究,进一步认识斑岩型钼矿的含矿裂隙规律,解决此类含矿裂隙发育复杂矿区的矿体对应连接问题,有效指导矿区找矿。通过野外统计、室内数据整理及综合分析,在马头矿区选取代表性钻孔6个、平硐1个及地表露头3个,进行含矿岩体及其围岩节理裂隙特征的统计分析,开展钼矿床含矿裂隙规律研究。对矿区岩体与围岩中的节理裂隙、石英脉、钾长石英脉、断裂破碎带特征进行统计分析,发现矿区岩体与围岩中的节理裂隙特征基本一致,主要节理裂隙有5组,主要矿体含矿优势节理裂隙走向NNE,倾向SE,倾角在40°左右。     

新疆元宝山金矿床锆石U-Pb、全岩Rb-Sr年代学及其地质意义

元宝山金矿床位于新疆鄯善县境内,属于东天山康古尔塔格金矿带,受秋格明塔什-黄山韧性剪切带控制。为探讨元宝山金矿床的成矿时代及其地质意义,本次研究开展了矿石石英Rb-Sr年代学、含矿围岩Rb-Sr、Sm-Nd及锆石U-Pb同位素年代学分析。(255.6±1.0)Ma的含矿围岩Rb-Sr同位素等时线年龄以及(256±14)Ma的石英Rb-Sr等时线年龄,限定了该矿床的形成时代,而(334.7±9.8)Ma的含矿围岩锆石U-Pb年代学数据表明,该矿床的含矿围岩为中石炭统。Sr、Nd同位素特征表明,成矿物质来源具有幔源特征并有壳源物质参与,而区内韧性剪切带右行走滑剪切及随后的抬升作用导致的压力和温度的降低应是元宝山金矿床形成的动力学背景。     

腾冲—梁河地区斑岩地质特征及含矿性判别

腾冲－梁河地区含矿斑岩主要分布在东部花岗岩带中的构造极复杂地段,斑岩种类复杂,岩体裂隙发育,岩石破碎,岩体自蚀变和围岩蚀变强烈,蚀变种类复杂,特征副矿物和微量元素总含量高,岩体形态为岩株、岩筒、大岩脉,接触面产状陡,围岩为泥盆—二叠系碎屑岩、碳酸盐岩     

西天山加满特铅银矿含矿围岩地球化学特征及构造背景分析

加满特铅银矿位于西天山伊什基里克成矿带,矿体主要赋存于下二叠统乌朗组火山岩中。通过对加满特铅银矿区含矿围岩进行岩石地球化学和LA-ICPMS锆石U-Pb测年分析,探讨火山岩形成构造环境与成岩时代。地球化学分析表明,加满特铅银矿含矿围岩为钾质玄武岩系列与钙碱性系列。微量元素和稀土元素表明,矿区火山岩产出构造环境为碰撞后板内伸展期裂谷环境。通过对含矿围岩进行锆石U-Pb测年,获得~(206)Pb/~(238)U加权平均年龄为(294.59±0.92)Ma,属早二叠世。     

四川丹巴铜镍铂矿床矿化类型及其意义——以杨柳坪铂镍矿床为例

杨柳坪铂镍矿床位于丹巴县城以南格宗乡境内,由杨柳坪、协作坪、正子岩窝三个矿段组成,为一以铂镍为主,铜、钴、金、银等伴生,并可以综合利用的大型铂镍矿床,矿体受岩体、构造及围岩控制斜列于含矿岩体中、下部和含矿岩体与围岩的接触带。矿石类型有熔离-热液型;热液交代型;贯入型。     

铅锌矿床类型划分评析

对铅锌矿类型的划分,主要有以成矿温度结合深度和典型矿物组合为基础、以围岩或含矿岩系为基础、以成因为基础、以综合矿床因素为基础、以含矿岩系结合矿床成因为基础的若干划分方案,各具特色,又有不完善之处。从反映客观地质规律和体现矿床内在差异和外在可把握的标志的原则出发,尝试将铅锌矿按成矿系统划分为岩浆、热液(水)、沉积、叠加改造4大类,再据成矿环境,围岩类型及蚀变,成矿时代,流体包裹体,铅、硫同位素,成矿条件等特征进一步划分出9个亚类。     

双桥—新路地区铀矿成矿条件分析

在前人研究的基础上,以铀源条件、构造条件、含矿主岩、围岩蚀变等热液型铀矿的主要控制因素为研究内容,较详细地总结和分析了大桥坞矿床(671)、白虎岩矿床(670)和杨梅湾矿床(621)及部分铀矿化点的成矿特征和控矿规律。发现各矿床(点)的含矿围岩虽然不尽相同,但围岩蚀变类型相近且构造控矿特征尤为显著,以此为依据构建了研究区典型铀矿床成矿模式(热液型),为后期借助模式找矿、预测评价等奠定了基础。     

内蒙乌拉山矿区金矿围岩蚀变特征及其找矿意义

围岩蚀变是由于含矿热液与围岩化学成分不同及物化条件的不平衡而引起的热液对围岩的交代作用。围岩蚀变特征从一个侧面反映了含矿热液中物质组份的带入与带出、热液性质的变化规律以及成矿物质活化迁移和沉淀富集的规律。通过对乌拉山矿区金矿围岩蚀变特征的研究,对于帮助我们确定找矿标志、指导野外普查找矿工作具有重要意义。     

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