二连盆地努和廷铀矿床成矿作用及成矿模式

通过研究努和廷铀矿床地质特征、成矿作用及地球化学特征,认为努和廷矿床为同生沉积后生改造型铀矿床。晚白垩世二连期湖泊发育区控制了矿床定位。矿床成矿作用经历了同生沉积成矿、后生改造和表生作用3个阶段,成矿年龄为85Ma、（41±5）Ma和6～13Ma。在总结矿床成矿地质特征、成矿作用及地球化学特征基础上,建立了努和廷铀矿床成矿模式。     

松辽盆地钱家店砂岩型铀矿成矿地质特征

通过对钱家店铀矿床产出的地质背景、地质构造环境、矿床铀矿物特征、蚀变地球化学特征、微量元素地球化学特征、成矿物质来源及成矿年代学等综合研究,认为钱家店铀矿床受"晚白垩世姚家期辫状河道洼地、晚白垩世嫩江期末反转隆升剥蚀构造天窗、NNE向贯通性基底断裂"三位一体控制,矿床成因类型为同生沉积后生叠加复成因型。这为进一步的找矿工作提供了依据。     

Metaliogenic characteristics of Qianjiadian sandstone uranium deposit in Songliao basin

通过对钱家店铀矿床产出的地质背景、地质构造环境、矿床铀矿物特征、蚀变地球化学特征、微量元素地球化学特征、成矿物质来源及成矿年代学等综合研究,认为钱家店铀矿床受“晚白垩世姚家期辫状河道洼地、晚白垩世嫩江期末反转隆升剥蚀构造天窗、NNE向贯通性基底断裂”三位一体控制,矿床成因类型为同生沉积后生叠加复成因型.这为进一步的找矿工作提供了依据.     

松辽盆地宝龙山铀矿床控矿因素与成矿模式研究

产于松辽盆地西南部的宝龙山铀矿床是盆地代表性矿床之一,开展矿床控矿要素和成矿模式的研究对推进盆地区域找矿工作具借鉴意义。文章通过对宝龙山铀矿床成矿地质背景分析与矿化特征研究,厘定矿床关键控矿要素为辫状河灰色砂体、反转背斜（剥蚀天窗）和流体叠加改造;通过矿石U-Pb同位素分析与等时线拟合获得了81.2 Ma、74.5 Ma、52.3 Ma和46.6 Ma等成矿年龄数据,表明铀成矿作用由晚白垩世末持续至古近纪早中期,具有多期次叠加成矿的特征。在此基础上结合区域构造演化和铀矿化发育特征分析,将矿床成矿过程划分为成岩预富集、油气改造扩大、层间氧化成矿、油气渗出保矿4个阶段,并构建了宝龙山铀矿床4阶段成矿模式,为矿区外围和新区铀矿勘查工作部署提供借鉴。     

巴音戈壁盆地构造演化对砂岩型铀成矿作用的制约

巴音戈壁盆地为中国北方重要的中新生代产铀盆地,盆地内发现多个铀矿床。通过研究发现,盆地构造演化与盆地内铀成矿作用的关系密切。盆地的构造演化可划分为早白垩世巴音戈壁-苏红图断陷期,该期形成盆地铀成矿的主要目的层巴音戈壁组上段,主要为扇三角洲-湖泊沉积,垂向上具有泥-砂-泥的储层结构,有利于层间氧化的发育;早白垩世银根期为断坳转换期,晚期转为坳陷期,主要为河流相沉积,盆地内保存有限;晚白垩世乌兰苏海期,主要为坳陷期,主要发育曲流河-冲积平原沉积。在古近纪盆地发生大规模反转抬升,形成区域剥蚀窗口,有利于成矿流体的运移和后生氧化。盆地内已发现铀矿床的成矿作用与主要的构造热事件密切相关,主要有三期,第一期早白垩世中晚109.7±1.5 Ma～115.5±1.5 Ma,第二期为晚白垩世晚期-古近纪45.4±0.6 Ma～70.9±1.0 Ma和第三期为新近纪12.3±0.2 Ma～2.5±0.0 Ma。矿床成矿作用整体表现为同沉积预富集,后期具有叠生铀成矿的特点。通过构造演化与铀成矿作用关系的研究,对盆地内铀成矿潜力进行了初步评价。     

诸广铀成矿区矿床成因探讨

本文通过对诸广地区内生铀矿床成矿地质背景分析,系统论述了矿区地质特征及矿床地球化学特征,对本区矿床成因进行了探讨,提出诸广地区存在富铀的前寒武纪结晶基底;成矿物质来源于上地幔流体与下地壳富铀前寒武纪结晶基底的混熔交代;成矿作用受晚中生代伸展裂陷构造——深源热流体演化机制控制,形成中高温热流体充填成矿的高品位脉型矿化和中低温热流体交代成矿的较低品位碎裂蚀变岩－微脉浸染型矿化。     

巴音戈壁盆地构造演化对砂岩型铀成矿作用的制约北大核心CSCD

巴音戈壁盆地为中国北方重要的中新生代产铀盆地,盆地内发现多个铀矿床。通过研究发现,盆地构造演化与盆地内铀成矿作用的关系密切。盆地的构造演化可划分为早白垩世巴音戈壁-苏红图断陷期,该期形成盆地铀成矿的主要目的层巴音戈壁组上段,主要为扇三角洲-湖泊沉积,垂向上具有泥-砂-泥的储层结构,有利于层间氧化的发育;早白垩世银根期为断坳转换期,晚期转为坳陷期,主要为河流相沉积,盆地内保存有限;晚白垩世乌兰苏海期,主要为坳陷期,主要发育曲流河-冲积平原沉积。在古近纪盆地发生大规模反转抬升,形成区域剥蚀窗口,有利于成矿流体的运移和后生氧化。盆地内已发现铀矿床的成矿作用与主要的构造热事件密切相关,主要有三期,第一期早白垩世中晚109.7±1.5 Ma^115.5±1.5 Ma,第二期为晚白垩世晚期-古近纪45.4±0.6 Ma^70.9±1.0 Ma和第三期为新近纪12.3±0.2 Ma^2.5±0.0 Ma。矿床成矿作用整体表现为同沉积预富集,后期具有叠生铀成矿的特点。通过构造演化与铀成矿作用关系的研究,对盆地内铀成矿潜力进行了初步评价。     

巴音戈壁盆地塔木素铀矿床地质特征及铀成矿模式研究

巴音戈壁盆地为中国北方重要的能源盆地。笔者通过对盆地内塔木素铀矿床地质特征研究,发现矿床产于因格井凹陷巴音戈壁期微斜坡,晚白垩世和古近纪剥蚀窗口的发育,为成矿流体向盆地内运移提供了有利条件;矿床的主要目的层为下白垩统巴音戈壁组上段二岩段,为扇三角洲-湖泊沉积,扇三角洲砂体发育。巴音戈壁组上段二岩段与巴音戈壁组上段一岩段、三岩段构成有利的"泥-砂-泥"地层结构,有利于含铀含氧水向盆地内运移和层间氧化作用的发生。矿床内氧化带可划分为完全氧化带、氧化还原过渡带和还原带,矿体主要位于氧化还原过渡带中,受氧化带前锋线和氧化还原过渡带控制。矿床内参与铀成矿作用的还原介质主要为内部还原介质和外部还原介质。内部还原介质为目的层本身的有机质、黄铁矿等;外部还原介质为巴音戈壁组上段一岩段、三岩段暗色泥岩中发育的有机质、深部油(气)等。盆地内铀矿化与盆地的构造热事件密切相关,铀成矿作用表现为3期,第一期早白垩世中-晚期((109.7±1.5)Ma～(115.5±1.5)Ma),第二期为晚白垩世晚期—古近纪((45.4±0.6)Ma～(70.9±1.0)Ma)、第三期为新近纪((12.3±0.2)Ma～(2.5±0)Ma)。塔木素铀矿床矿体主要为砂岩型、砂泥混合型、后生泥岩型和同沉积泥岩型,矿体受层间氧化带和沉积相变控制明显。通过矿床构造、目的层沉积体系、氧化带、有机质和铀矿化等特征的研究,建立了矿床铀成矿模式和矿体成因模型,为后期铀成矿作用标志的研究奠定了基础。     

诸广地区内生铀矿床深源成矿地质流体地球化学特征及成矿模式

本文在分析区内内生铀矿床成矿地质背景的基础上,系统地论述了矿化地质特征及成矿地质流体地球化学特征,提出了本区内生铀矿床成矿模式。本文首次提出本区存在富铀的前寒武纪结晶基底;成矿地质流体是上地幔流体与下地壳富铀的前寒武纪结晶基底混熔交代的产物,成矿的铀主要来源于成矿地质流体本身;成矿作用受统一的晚中生代伸展裂陷构造-深源热流体演化机制控制,形成中高温热流体充填成矿的高品位脉型矿化和中低温热流体交代成矿的较低品位碎裂蚀变岩-微脉浸染型矿化。     

沽源-红山子铀成矿带核桃坝铀矿床矿相学和成矿年代学研究

核桃坝矿床是著名的沽源-红山子铀成矿带上新近勘查突破的重要铀矿床之一。为恢复成矿过程、划分成矿阶段和探讨矿床成因,本文开展了系统的矿相学和成矿年代学研究,以期为区内铀矿勘查和找矿突破提供理论支持。矿相学研究表明,矿床矿石矿物以铀石为主,成矿作用可划分为早期钠长石化交代阶段、早期热液成矿阶段、晚期热液成矿阶段和成矿后阶段四个阶段。核桃坝矿床属于碱交代型(钠交代)热液铀矿床。沥青铀矿U-Pb同位素表观年龄、电子探针化学年龄以及等时线年龄综合研究显示,矿床形成时代应在99. 1Ma左右,是晚白垩世成矿作用的产物。核桃坝矿床可能是富铀岩体在碱交代作用后形成流体(富铀含硅酸成矿流体)在外部条件改变的情况下沉淀成矿。因此,矿体的定位与富铀岩体关系密切,富铀岩体附近的开放空间(断裂构造、层间破碎带等)是重要的找矿方向。     

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