埋藏后生作用对生物壳体87Sr/86Sr的影响研究

根据小渡口剖面２８层有孔虫、介形虫、腹足类生物壳体的微观观察、微量元素及其比值、＾８７Ｓｒ／＾８６Ｓｒ与微量元素特征对比经及水－岩反应＾８７Ｓｒ／＾８６Ｓｒ的混合模式,显示生物壳体遭受了埋藏后生作用,但对生物壳体原始的＾８７Ｓｒ／＾８６Ｓｒ比值基本没有改变或影响甚微,推测参与埋藏后生作用的流体与生物壳体具有相近的Ｓｒ同位素组成或较悬殊的Ｓｒ含量。同时,实际研究表明评价和判别埋藏后生作用对生物壳体原     

东太平洋早中新世Sr87／Sr86和CaCO3的短周期旋回及其古海…

以５ｃｍ为间隔取得东太平洋５７９４岩心早中新世超微化石软泥须（２４．０６～２２．０６Ｍａ）的５５个样品,用同位素质谱仪、耦合等离子光谱仪和化学溶解当分别对尼中可溶碳酸盐组分的＾８７Ｓｒ／＾８６Ｓｒ、全岩的Ａｌ２Ｏ３和ＣａＣＯ３含量进行了测定。结果显示,＾８７Ｓｒ／＾８６Ｓｒ和ＣａＣＯ３呈反射发育了２个完整旋回和１个半旋回。＾８７Ｓｒ／８６Ｓｒ和ＣａＣＯ３短期旋回具有重要的古海洋学意义：（１）＾８７     

(古)盐度研究的一种重要工具--锶同位素

本文详细地阐述了海水-陆表水双元体系中锶同位素的混合原理、混合水体中87Sr/86Sr值与盐度的定量关系.利用Sr同位素不随生物、化学作用过程发生分馏作用及Sr与Ca化学性质相似等特征, 地层、沉积物中生物壳体和碳酸盐岩87Sr/86Sr值可作为沉积水体(古)盐度确定的一种有用工具.文中详细地综述了国内外在这方面的研究进展,并讨论了成岩后生作用对生物壳体和碳酸盐岩87Sr/86Sr原始值的影响作用,以及可能存在的一些问题.     

脉状黝铜矿型铜矿床的稳定同位素组成及其成因意义

脉冲黝铜矿型铜矿床是产于兰坪－思茅盆地中的一种新的铜矿床类型。碳酸盐及ＣＯ２包裹体的δ＾１３Ｃ值大多在－４‰～－７‰之间变化,显示碳来自地幔。矿石中铅同位素组成与盆地中喜马拉雅期碱性岩长石中铅的同位素组成一致,方解石和铁白云石的＾８７Ｓｒ／＾８６Ｓｒ比值接近或稍高于碱性岩的＾８７Ｓｒ／８６Ｓｒ的比值,显示矿石锶、铅与碱性岩锶、铅是同源的,均来自于上地幔。硫化物中硫的δ＾３４Ｓ值大多集中在０～－４‰     

我国某些元古宙及早寒武世碳酸盐岩石的锶同位素组成

本文报道了我国某些元古宙及早寒武世碳酸盐岩石锶同位素的测量结果，样品采自蓟县中元古界和峡东震旦－寒武系标准剖面，共４６件样品５４个测定数据。样品分析分别在澳大利亚国立大学和宜昌地质矿产研究所同位素实验室进行。取得的测定数据经空白校正和年龄校正，给出样品形成时＾８７Ｓｒ／＾８６Ｓｒ的初始值，测定中用ＮＢＳ－９８７和ＮＢＳ－６０７标准物质监探仪器状态和分析过程，得到的＾８７Ｓｒ／＾８６Ｓｒ值的精度好于     

长江,黄河流域泛滥平原细粒沉积物^87Sr＼^86Sr空间变异的制约因 …

黄河和长江流域泛滥平原细粒沉积物的Ｓｒ同位素组成存在较大差异。前者的＾８７Ｓｒ／＾８６Ｓｒ变化范围较小,为０．７１２８６８～０．７１８８６０,平均值为０．７１５４７４;后者变化范围较大,为０．７１３０３５～０．７３６５０２,平均值为０．７２１４３８。黄河流域中、上海细粒沉积物的＾８７Ｓｒ／８７Ｓｒ低于下游;而长江流域细粒沉积物的＾８７Ｓｒ／＾８６Ｓｒ中游高于上、下游,且南侧高于北侧。由ＮＷ向ＳＥ,     

塔中古生界油田水的成因和混合的证据

塔中地区奥陶纱、志留系和石炭系油田水的主元素、微量元素、＾８７Ｓｒ／＾８６Ｓｒ、δＤ、δ＾１８Ｏ及全岩的＾８７Ｓｒ／＾８６Ｓｒ测试结果表明,油田水相对于海水蒸发曲线,富Ｓｒ＾２＋、Ｃａ＾２＋、ＣＦ而贫Ｋ＾＋、Ｍｇ＾２＋,系水－岩反应改造的产物。远高于海水的＾８７Ｓｒ／＾８６Ｓｒ值表明油田水具有钾长石等矿物溶解的影响。油田水＾８７Ｓｒ／＾８６Ｓｒ－１／Ｓｒ的关系显示具有两种混合趋势,一种是奥陶系油田     

一个古元古代A型流纹岩

山西吕梁群流纹岩是一个古元古代的弱碱性火山岩,它具有高ＳｉＯ２,Ｎａ２Ｏ＋Ｋ２Ｏ和Ｚｒ,Ｇａ等高场强元素和高ＦｅＯ＾＊／ＭｇＯ,Ｒｂ／Ｓｒ和Ｇａ／Ａｌ比值,以及低ＣａＯ,Ｓｒ和Ｅｕ／Ｅｕ＾＊的地球化学特征,相似于Ａ型花岗质岩石。它形成于大陆边缘裂谷环境,化学成分及同位素特征为高εＮｄ（ｔ）值,低（＾８７Ｓｒ／＾８６Ｓｒ）ｉ值,表明流纹岩的原始岩浆由下地壳晚太古代变质岩受裂谷岩浆和热流作用的影响部分     

南天山托云盆地晚白垩世——早第三纪玄武岩的地球化学特征 …

托云盆地晚白垩世－－早第三纪碱性橄榄玄武岩Ｓｒ、Ｎｄ、Ｐｂ同位素组成表明,本区玄武岩以低Ｓｒ、Ｐｂ和相对高的Ｎｄ同位素值（＾８７Ｓｒ／＾８６Ｓｒ为０．７０３５５４￣０．７０３８８４;＾１４３Ｎｄ／＾１４４Ｎｄ为０．５１２８３８￣０．５１２９０４;＾２０６Ｐｂ／＾２０４Ｐｂ为１８．００６３￣１８．４７２０;＾２０７Ｐｂ／＾２０４Ｐｂ为１５．４４１１￣１５．５０６０;＾２０８Ｐｂ／＾２０４Ｐｂ为３７．     

四川盆地南北缘志留系的锶和碳、氧同位素演化及其地质意义

通过对四川盆地北缘广元地区及南缘綦江地区上奥陶统及下志留统地层的８７Ｓｒ／８６Ｓｒ、δ１３Ｃ及δ１８Ｏ的系统测定,取得了沿地层剖面变化的同位素组成规律。研究结果表明,在盆地南缘８７Ｓｒ／８６Ｓｒ值高于地质历史中海水的平均值,其原因是本区为受板块内古陆控制的缓坡环境,大量陆源锶的混入增加了８７Ｓｒ／８６Ｓｒ的值。８７Ｓｒ／８６Ｓｒ值在上奥陶统至下志留统地层交界处、Ｒｈｕｄｄａｎｉａｎ／Ａｅｒｏｎｉａｎ（鲁丹期／艾隆期）交界处具正峰波动,反映了此时海平面的短时下降。但从Ｒｈｕｄｄａｎｉａｎ至Ｔｅｌｙｃｈｉａｎ（特里奇期）,８７Ｓｒ／８６Ｓｒ逐渐降低。从Ａｅｒｏｎｉａｎ至Ｓｈｅｉｎｗｏｏｄｉａｎ（舍因伍德期）早期,盆地南北缘的δ１３Ｃ值处于逐渐上升的过程之中,而δ１８Ｏ则相反。同位素的演化特征说明本区当时为海进时期,海平面不断上升,与全球性海平面变化相吻合。由于受区域构造运动的作用,Ｓｈｅｉｎｗｏｏｄｉａｎ之后的全球持续海进对本区无影响。     

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