塔里木盆地北部中下奥陶统碳酸盐陆棚—盆地的层序地层分析

露头剖面的层序地层分析是层序地层研究的重要内容之一，本文对塔里木盆地北部一组发育在不同沉积背景上的碳酸盐岩陆棚－盆地的层序，进行了详细的沉积学、古生物学和地球化学研究，系统探讨了层序中各体系域、层序界面和密集段的主要特征，通过对典型层序的分析发现，对于碳酸盐岩，特征明显，体系域易于识别的层序，发育在较浅水的背景上，在深水条件下，体系域较难识别，由此可以推论得到，在很深水的盆地中，多个层序可完全复合     

塔里木盆地北部一组从碎屑岩到碳酸盐岩的典型层序分析

本文对塔里木盆地北部露头剖面中一组从碎屑岩到碳酸盐岩的典型层序进行了详细的沉积学、古生物学和地球化学研究，系统探讨了该剖面中碎屑岩和碳酸盐岩的层序特征，首次发现在具粗碎屑沉积的高能滨岸地带可出现由海进体系城叠置海进体系域的层序叠置方式，这在以前的文献中尚未见报道。对于发育在浅水碳酸盐陆棚背景上的碳酸盐岩层序，各体系域特征明显，易于识别，但在浅水处，密集段不发育。通过对典型层序的详细解剖分析，结合层     

碳氧同位素演化与碳酸盐岩层序地层学关系研究——…

结合碳酸盐岩层序地层分析，首次系统测定了马平组碳，氧同位素值，并对其演化规律与层序地层的关系进行了探讨，研究结果表明：马平组内δ＾１３Ｃ，δ＾１８Ｏ值变化范围分别是－２．５６‰～＋３．８９‰和－８．１６‰～－６．０２‰（ＰＤＢ）准层序为δ＾１３Ｃ值向上逐渐减小，海进体系域（ＴＳＴ）和高水位体系域（ＨＳＴ）内δ＾１３Ｃ值分别呈增加和减小的趋，层序界面处δ＾１３Ｃ，δ＾１８Ｏ值均表现为负异常，控制层序     

南堡凹陷古近系层序地层格架中烃源岩分布与生烃特征研究

南堡凹陷油气资源丰富,古近系主要分布有沙三段、沙一段和东三段三套有效烃源岩。在层序地层学研究的基础上,应用有机地球化学、有机岩石学和沉积有机相等研究手段和方法对东三段、沙一段和沙三段不同层序和同一层序不同体系域中烃源岩特征进行综合研究。结果表明,南堡地区烃源岩非均质性特征明显,烃源岩生烃的层位主要分布于SQ9、SQ5~SQ8、SQ2和SQ1的湖扩展体系域和早期高位体系域,SQ2为优质烃源岩段。造成这种非均质性的主要原因是不同体系域的沉积特征,这影响着烃源岩有机质类型和保存条件。     

上扬子地区五峰组-龙马溪组页岩层序地层及演化模式

学者们在页岩层序划分与构成等方面还存在较大分歧;其次,现有研究中针对页岩非均质性在层序格架内的变化特征及成因规律方面亦有不足.五峰组-龙马溪组页岩是上扬子地区重要的页岩气勘探层位之一,通过钻井岩心、露头剖面、常规测井、能谱测井和地球化学参数等资料,对上奥陶统五峰组-下志留统龙马溪组黑色页岩层序地层学进行了定量分析.在五峰组-龙马溪组识别出3个三级层序,其中五峰组为一个三级层序,进一步划分出海侵体系域（五峰组下部黑色页岩）和高位体系域（五峰组上部观音桥段）;龙马溪组一段作为一个三级层序,进一步划分出海侵体系域、早期高位和晚期高位体系域;龙马溪组二段和三段为一个三级层序,进一步划分出低位体系域、海侵体系域和高位体系域.以不同体系域为单元分析了五峰组-龙马溪组层序发育与沉积环境特征,揭示了各体系域内古生产力与水体氧化还原条件对有机质富集的控制机理,总结并提出了系统的五峰组-龙马溪组黑色页岩层序地层垂向演化模式.      

塔里木柯坪地区奥陶系层序地层与同位素地球化学响应特征

塔里木盆地柯坪地区奥陶系发育浅水碳酸盐岩台地、深水陆棚-盆地两大类沉积体系和局限台地、开阔台地、陆棚和盆地等4种相类型。通过露头剖面的详细观察,在该区识别出局部暴露不整合和淹没不整合两类层序界面,以此为依据将该区奥陶系划分为9个三级层序。通过对层序格架内碳同位素和元素地球化学组成分析表明,不同层序界面及层序内不同体系域的δ13C和元素地球化学组成有明显的差异,并呈现出有规律性变化,反映出该区奥陶纪发生了多次海平面升降变化。研究表明同位素和地球化学特征可以作为层序地层学研究的辅助标志。     

海进体系域碳氧同位素地球化学响应——以黔西南地区三叠系为例

层序地层研究表明，位于扬子地块西南缘的黔西南地区在中三叠世末期（相当于Ladinian-Carnian期）出现了一次与全球同步的大规模海侵，形成了一个向上变深的碳酸盐岩台地淹没沉积层序。垄头组顶部和竹竿坡组分别是海进体系域（TST）的下、上部分。碳、氧同位素研究表明，垄头组顶部自下而上δ（^18O）持续增大，而δ（^13 C）先逐渐增大，后在顶部界面附近快速下降，反映了垄头组顶部在暴露环境下氧化作用的结果。竹竿坡组δ（^13 C）自下而上逐渐增大，δ（^13 C）总体呈现逐渐减小趋势，反映了海平面变化特征。研究认为，海进体系域的δ（^13 C）和δ（^18 O）演化不但反映了海平面和沉积环境变化，同时对密集段（CS）、层序界面和古暴露面等也有很好的识别作用，在层序地层研究中具有重要的意义。     

陆相层序地层学标准化研究和层序岩相古地理：以四川盆地上三叠统须家河组为例

层序地层标准化是未来层序地层研究重要发展方向,层序成因模式、标准建立、工业化应用是核心;层序地层学分析的标准工作流程强调识别沉积物成因类型和层序地层界面的原因,向共同方法迈进。针对中国陆相沉积复杂多变的特点,可以利用野外露头伽马仪、元素捕获仪、探地雷达以及元素地球化学等多种手段进行高精度层序划分,识别三级层序界面与洪泛面,建立露头-钻井-地震层序地层格架。可以依据陆相湖盆沉积旋回在古水深、古气候、沉积地球化学特征等方面的定量表征,综合开展高精度层序地层研究。在四川盆地上三叠统须家河组层序岩相古地理研究中,将须家河组划分为5个三级层序,须家河组二段上、下亚段实际上是2个不同三级层序的基准面上升与下降体系域沉积,须二下段发育进积型三角洲,上段发育退积型三角洲;由于三角洲砂体发育机理明显不同,导致须二下段储层厚度和物性均好于上段,产层主要分布在下段。在层序岩相古地理研究基础上,进一步明确须二、四、六段是主要储层发育段,层间泥岩也可作为烃源岩。须一、三、五段是主要烃源岩发育段,盆缘规模较小的三角洲砂体也是重要的储层。     

塔里木盆地北部奥陶系层序地层研究

以层序地层学为指导，通过对塔里木盆地北部奥陶系的深入研究，确定奥陶系由２个超层序组成；超层序ＳＳｑ１相当于下奥陶统地层，由４个层序组成。层序的发育以高水位体系域为主，水进体系域相对不太发育；低水位体系域分布较局限。各层序中发育的密集段向盆地方向逐渐合并成复合密集段，表现为“梳状结构”。超层序ＳＳｑ２相当于中、上奥陶统，也由４个层序组成，下部２个层序以低水位浊积扇沉积为主，上部２个层序中体系域发育齐全。最后讨论了碳酸盐岩隆与层序发育的关系     

北部湾盆地涠西南凹陷流沙港组岩性圈闭形成条件

涠西南凹陷为北部湾盆地一典型的箕状断陷,古近纪经历3次构造运动,地层表现为多旋回沉积特征,发育多套生储盖组合。通过对古近系沉积地层进行层序地层格架分析,认为始新统流沙港组二段(流二段)层序、流沙港组一段(流一段)下层序和流一段上层序是岩性圈闭发育的主要层序。古近系三级层序中不同体系域类型严格控制着岩性圈闭的发育和形成,具体表现为流二段层序的岩性圈闭主要发育于低位体系域和湖侵体系域,流一段下层序的岩性圈闭主要发育于低位体系域,流一段上层序的岩性圈闭主要发育于高位体系域。凹陷的多物源充填所形成的多种沉积体系类型也是形成多种类型岩性圈闭的重要原因。发育于陡坡带的近岸水下扇岩性圈闭、扇三角洲岩性圈闭、缓坡带浊积水道岩性圈闭和洼槽带湖底扇岩性圈闭为有利的圈闭目标。     

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

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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