早元古代滹沱群玄武岩Rb-Sr、Sm-Nd同位素体系初论

本文给出的滹沱群下亚群青石村组玄武岩Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ全岩等时线年龄为２０４５．８±１７和２３６９±３０Ｍａ（Ｚ），角门石４０Ａｒ－３９Ａｒ坪年龄和最高视年龄为１３６４±１９和１９３２±１９Ｍａ（１）；中亚群河边村组玄武岩Ｒｂ－Ｓｒ全岩等时线年龄图的投点呈完全离散状，Ｓｍ－Ｎｄ全岩等时线年龄为２３２２±３１Ｍａ（２），角门石４０Ａｒ－３９Ａｒ坪年龄和最高视年龄为１３６０和１７４２±１７Ｍａ（１）。根据上述Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ数据与已知青石村组、河边村组单颗粒锆石Ｕ－Ｐｂ法确定的成岩年龄２４５０±１０和２４００±２０Ｍａ（２）的明显差别，４０Ａｒ－３９Ａｒ均揭示为较典型受扰动的年龄谱和较发育的透人性构造、晚期岩脉等地质证据，认为Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ是重设的同位素体系。     

江西菖蒲盆地中生代火山系划分的新认识

本文分析了江西寻乌菖蒲盆地中生代晚期火山岩系划分的现状及存在的问题,提出了以不整合面为界,将火岩岩纱刑 分为上、下两个不同时期的火山岩系,即下火山岩系称为田 火山岩系称为版石群,依据岩性岩相特征,可进一步将余田 划分为水头迳组和菖蒲组,版石群划分为合水组和优胜组。余田群草蒲组玄武岩全岩Ｒｂ－Ｓｒ等时线年龄为１７６Ｍａ,流纹岩全岩Ｒｂ－Ｓｒ等时线年龄为１５０Ｍａ;版石群优胜组流纹岩全岩Ｒｂ－Ｓｒ等时     

江西菖蒲盆地中生代火山岩系划分的新认识

本文分析了江西寻乌菖蒲盆地中生代晚期火山岩系划分的现状及存在的问题,提出了以不整合面为界,将火山岩系划分为上、下两个不同时期的火山岩系,即下火山岩系称为余田群,上火山岩系称为版石群。依据岩性岩相特征,可进一步将余田群划分为水头迳组和菖蒲组,版石群划分为合水组和优胜组。余田群菖蒲组玄武岩全岩Ｒｂ－Ｓｒ等时线年龄为１７６Ｍａ,流纹岩全岩Ｒｂ－Ｓｒ等时线年龄为１５０Ｍａ;版石群优胜组流纹岩全岩Ｒｂ－Ｓｒ等时线年龄为１０４Ｍａ。因此,余田群的地质时代为中侏罗世—晚侏罗世早期,版石群的地质时代为早白垩世。     

吉林南部太古代花岗岩Sm—Nd,Rb—Sr同位素年龄测定

吉林南部太古代花岗质岩石经同位素年龄测定，英云闪长质片麻岩类的Ｒｂ－Ｓｒ全岩等时年龄为２４１７±１２１Ｍａ，Ｓｍ－Ｎｄ全岩等时年龄为２４１６±１２７Ｍａ，模式年龄为２８４０Ｍａ；辉石花岗岩类的Ｒｂ－Ｓｒ全岩等时年龄为２３４６±２３２Ｍａ，Ｓｍ－Ｎｄ全岩等时年龄为２４４０±１５９Ｍａ，模式年龄为２７８０Ｍａ。反映这些岩石都是在太古宙晚期形成的，并且是在较短的时间间隔内完成的，其模式年龄与华北地台太古宙主体地壳的形成时代一致。     

早元古代滹沱群玄武岩Rb—Sr,Sm—Nd同位素体系初论

本文给出了的滹沱群下亚群青石村组玄武岩Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ全岩等时线年龄为２０４５．８±１７和２３６９±３０Ｍａ（２σ），角闪石＾４０Ａｒ＾－＾３９Ａｒ坪年龄和最高视年龄为１３６４±１９和１９３２±１９Ｍａ（１σ）；中亚群河边村组玄武岩Ｒｂ－Ｓｒ全岩等时线年龄图的投点呈完全离散状。     

北淮阳东段几组铷锶等时线年龄及其区域地质意义

采于北淮阳东段的４组全岩Ｒｂ－Ｓｒ等时线年龄表明：出露于金寨县李桥和肥西县防虎山的变质岩层为中元古界（１５９５～１７２６Ｍａ）；大别山北东缘变质表壳岩为晚元古代（７５９～８２２Ｍａ）佛子岭群成分     

北淮阳东段几组铷锶等时线年龄及其区域地质意义

采用北淮阳东段的４组全岩Ｒｂ－Ｓｒ等时线年龄表明：出露于金寨县李桥和肥西县防虎山的变质岩层为中元古界（１５９５￣１７２６Ｍａ）；大别山北东缘变质表壳岩为晚元古代（７５９￣８２２Ｍａ）佛子岭群成分。     

山东中生代橄榄安粗岩系火山岩的地质,地球化学…

山东中生代橄榄安粗岩系火山岩订分布在沂沭断裂及其两侧的断陷型陆相火山盆地，为早白垩世火山活动的产物。Ｒｂ－Ｓｒ全岩等时年龄变化于１１１．４￣１１９．６Ｍａ，岩石组合主要为粗面玄武岩－橄榄安粗岩－安粗岩－粗面岩。     

郯庐断裂带北段形成的年代学及其意义

对郯庐断裂带北段内的依兰－伊通断裂带测定断民支岩的黑云母单矿物＾４０Ａｒ／＾３９Ａｒ坪年龄为１００±２．３－９５．７±２．７４Ｍａ，同时测定了带内的辉绿岩全岩Ｒｂ－Ｓｒ等时线年龄为１００±５．９Ｍａ，而辉绿岩中辉石单矿物的＾４０Ａｒ／＾３９Ａｒ坪年龄为１０５Ｍａ。结合断裂切过下白垩统泉头组，表明左行走滑断裂形成于１００Ｍａ左右，即早白垩世末期。     

山东金伯利岩蒙山矿研究的新进展：上地幔含太阳离子Cr,Ti,Fe…

本文回顾了国内外金伯利岩及其它地幔岩中发现的Ｋ、Ｂａ、Ｃａ、ＲＥＥ的Ｔｉ－Ｃｒ－Ｆｅ－Ｍｇ氧化物矿物的研究现状，包括沂蒙矿系列、蒙山矿系列及柱红石系列。在此基础上概括性地总结了笔者近一、二年对山东蒙阴金伯利岩中蒙山矿矿物所进行的微区矿物学方向研究取得的最新进展，包括①揭示了Ｋ、Ｂａ、Ｃａ、ＲＥＥ等半径较大的元素在蒙山矿中的不均匀分布特点；②首次在金伯利岩中发现了蒙山矿系列矿物的Ｃａ端元－Ｃａ蒙山矿     

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

正~~     

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