延边中西部地区钼矿成矿地质特征

本文通过延边中西部地区已知钼矿床(点)时空分布规律及区域成矿地质条件以及对具有代表性矿床(点)的野外实际调研工作。从钼矿与断裂、岩体、围岩蚀变等方面的关系揭示了钼矿成矿的基本特征;从钼矿的矿化类型、空间分布规律等方面论述了钼矿的矿化特征。对该区的钼矿勘查工作具有一定的指导意义。     

辽宁河坎子钼矿床地质特征及成矿远景预测

辽宁省河坎子钼矿床位于喜峰口—凌源多金属成矿带。从钼矿形成的控矿因素、成矿地质特征、矿床成因入手,分析钼多金属矿区钼矿床形成的主要地质因素、矿床形成的地质作用,预测区内成矿远景,指出河坎子钼矿床为斑岩型矿床,并具大中型矿床成矿远景。     

新疆大红柳滩地区稀有金属矿成矿地质特征及找矿前景

大红柳滩地区稀有金属矿是上世纪60年代初新发现的稀有金属矿产地,由于海拔高,交通困难,至今没有进行深入的地质勘查工作。通过对该地区所处成矿地质背景、成矿地质特征、矿产分布规律、成矿规律、控矿因素及矿床成因进行分析,认为该区及外围均具有很大的找矿潜力,加强综合找矿,可望实现新的突破。     

辽宁有色金属矿山新一轮地质探矿思路谈

根据辽宁省有色金属矿山资源现状,加强矿山新一轮地质探矿是一项十分必要而紧迫的任务.兰家沟特大型钼矿、高家堡子大型银多金属矿和吴家屯铅锌矿的发现,说明有色金属矿山具有较大的资源潜力和找矿远景,也为新一轮地质探矿起到了成功的示范作用.在新一轮地质探矿中要发挥地勘部门和有色矿山各自优势和积极性,密切合作,开发多年积累的老资料.在现代地质成矿理论的指导下,重视研究矿田(床)成矿规律,预测资源潜力,分析找矿远景、通过找矿思路创新、勘查技术方法创新.突破新的成矿区段,新类型矿床和新矿种.实现新一轮地质探矿的目标.     

福建三明眉山钼矿床地质特征及成因探讨

根据三明眉山钼矿区域地质背景和矿区勘查资料,通过对矿区矿床地质、地球化学和成矿地质条件的综合分析,认为该矿床产于晚侏罗世二长花岗岩与早白垩世花岗闪长岩接触部位的斜节理密集带中。成矿大致可分为2个阶段,即成矿背景阶段、中高温热液成矿阶段,认为属燕山晚期中高温热液充填交代型钼矿床。     

安徽金寨县沙坪沟钼铅锌矿田两期成岩成矿作用

安徽金寨县沙坪沟钼矿床是近年来秦岭-大别成矿带发现的超大型斑岩钼矿床,已探明钼资源储量234×104t。在沙坪沟钼矿床外围发育多处铅锌矿床(点)。本文通过对外围3个铅锌矿床闪锌矿Rb-Sr同位素定年,获得120±2Ma的成矿年龄,而钼矿床成矿年龄则在115~111Ma,显示出矿田内铅锌矿床的成矿时代早于钼矿床。结合区域构造背景、控矿构造、赋矿围岩及围岩蚀变等地质特征分析,认为斑岩钼矿床和铅锌矿床为两个独立的成矿系统,热液型铅锌矿成矿系统形成早于斑岩型钼矿成矿系统。据地质勘查和同位素年代学资料,矿田岩浆岩分为两期,第一期为早白垩世早期花岗闪长岩、二长花岗岩,是热液型铅锌矿成矿系统主要赋矿围岩,第二期为早白垩世晚期石英正长岩和花岗斑岩,是斑岩型钼矿成矿系统的主要赋矿围岩。矿床C、H、O、S等稳定同位素相关研究表明热液型铅锌矿成矿系统和斑岩型钼矿成矿系统均是两期岩浆热液演化的结果。因此矿田存在两期成岩成矿作用。两个成矿系统矿石铅同位素组成不同,斑岩型钼矿成矿系统矿石铅同位素比值相对较高,变化范围大。铅锌矿床为早于斑岩钼矿床的独立成矿系统的认识合理解释了沙坪沟钼矿床为单一钼矿体,不含铅锌铜等不同于东秦岭斑岩钼矿床地质现象。区内两期成岩成矿作用均发生于晚侏罗─早白垩世构造体制转换阶段及以后伸展期。     

中国钼矿床主要类型及成矿预测

中国钼矿资源丰富,遍布各省区,矿床类型多,元素组合多样。在广泛搜集文献资料与实地研究的基础上,总结了中国钼矿资源特点,并综合考虑矿床成因、赋存状况、控矿因素、矿石成分及结构构造等因素,将中国钼矿床类型划分为4组12类19个矿床式;进一步归纳了各类典型矿床矿体赋存状况、热液蚀变、矿化组合特征。同时从构造、岩浆等方面分析了我国钼矿的找矿潜力和中国大陆造山环境下斑岩型钼矿形成的地质条件背景;总结了各种类型钼矿的成矿特征,通过对大地构造背景、构造-岩浆-流体事件及元素组合规律等的研究,指出以岩浆型钼矿为主,热液型钼矿次之的研究、勘查层次;重点对东秦岭、燕辽及特提斯钼成矿区进行了预测,明确了这些地区下一步钼矿勘查工作的重点,这对我国钼矿地质找矿和矿床研究具有指导意义。     

东昆仑拉陵高里地区铁铜多金属矿成矿特征 与找矿潜力分析

昆仑成矿带是青海省近年来找矿成果最为显著的地区之一。随着地质调查工作的不断深入,勘查及科研成果资料的日益丰富,研究大型-超大型矿床成矿条件、控矿因素和分布规律,完善成矿理论和矿床模型,对推动东昆仑矿产勘查至关重要。拉陵高里地区相继发现了红山铁矿点、小孤山铁矿点、拉陵高里河东铁矿点及拉陵高里河下游铁铜矿点等,是东昆仑地区重要的铁矿资源储备基地,本文对区内典型矿床拉陵高里河下游铁铜矿床的成矿地质背景、矿体特征、矿石成分、围岩蚀变等进行综合研究,系统总结矿床的地质特征、控矿因素、成矿规律及找矿标志,对区内找矿具有指导意义。     

河南省母山钼矿地质特征及找矿方向

通过对河南省母山钼矿地质特征的研究,提出大别山地区钼多金属矿床具有从中心向外由高温矿床到中低温矿床依次展布的各自独立的内成矿带、中间成矿带、外成矿带分布特征,从而构成“卫星式“环带状分布的成矿系列格局.将这一规律用于指导综合找矿,一可以在已知中高温热液矿床的外围注重寻找中低温热液矿床,二可以从已发现的中低温热液矿床的环带状或弧状分布的格局来预测中高温热液矿床的位置,以期发现隐伏盲矿.     

辽宁省杨家杖子钼矿田成矿模式与找矿标志

杨家杖子钼矿田位于著名的八家子-杨家杖子岩浆热液成矿带的中部,成矿带内由于沉积地层有利、岩浆岩发育、断裂构造复杂等一系列有利条件而形成了一大批大、中型钼矿床.以区域地质特征为基础,重点对矿田内最发育的兰家沟钼矿、杨家杖子钼矿和北松树卯钼矿成矿地质背景、矿床地质特征进行了详尽的研究,并结合成矿物质来源、成矿温度、成矿时代重新确定矿床成因,总结成矿主要过程,从而建立矿田区域成矿模式.在此基础上总结了杨家杖子钼矿田地质、物探、化探找矿标志.     

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