准噶尔盆地冲积扇储层流动单元研究

储层流动单元研究可以更好地预测剩余油的分布,指导油田开发.以准噶尔盆地百口泉油田百21井区百口泉组冲积扇相储层为例,利用岩心、测井资料开展流动单元研究,在储层细分对比的基础上,采用定性与定量相结合的方法将研究区流动单元分为E,G,F,P等4种类型.描述了各类流动单元孔隙结构特征、空间分布规律及其与沉积微相间的相互关系.总结出冲积扇流动单元模式,并分析了各类流动单元与剩余油分布的关系.研究表明:冲积扇储层中E类流动单元多分布于主槽流沟的中心部位;G类流动单元多呈宽带状分布于主槽微相的沟间滩及侧缘槽微相砂体的侧翼;F类流动单元一般都在辫流砂岛、辫流滩地;P类流动单元一般分布在扇间滩地或漫洪、漫流带.剩余油多分布于横向渗流屏障附近流动单元的边缘部位和流动单元接合处.     

东营凹陷沙河街组岩性油藏“多元控油—主元成藏”特征分析

东营凹陷沙河街组岩性油藏的形成与分布在宏观上受多种元素的控制,这些宏观地质控制因素包括构造带类型、沉积体系域类型、储集相类型、烃源岩条件和盆地温压条件等.根据岩性油藏的自身特点分析认为,东营凹陷沙河街组岩性圈闭能否成藏主要受到4大主控元素的控制,分别为岩性油藏输导通道因素、流体动力因素、储层临界物性因素、砂体封闭性因素.经研究在牛庄洼陷发现沙河街组岩性油藏具有“三元主控”的特征.     

潍北凹陷孔店组烃源岩生物标志物特征及地球化学意义

通过对潍北凹陷孔店组烃源岩有机质丰度、类型、成熟度及生物标志物的研究,发现孔店组烃源岩重排甾烷含量低,C27,C28和C29规则甾烷含量较多,C29甾烷的20S/(S R)和C29ββ/(ββ αα)比值分别在0.12～0.38和0.3～0.45之间;在萜类化合物中,奥利烷含量低,γ蜡烷与C30藿烷比值在0.1～0.37之间.研究结果表明孔店组烃源岩生源以高等植物为主,混有一定比例的藻类等低等水生生物,沉积环境为含盐度低的弱还原-弱氧化湖沼相,烃源岩有机质处于低熟-成熟阶段.     

川西前陆盆地须家河组沉积相及岩相古地理演化

川西前陆盆地上三叠统须家河组是油气勘探的重点层位.依据新的地层划分方案、大量钻井、露头及岩芯资料,结合区域地质特征,详细研究了须家河组沉积相、岩相古地理特征及其演化.结果表明:研究区内主要发育了冲积扇、湖相三角洲、湖泊、海相三角洲、滨岸和海湾六种主要的沉积相类型;古地理演化经历了由海相环境-海陆过渡相环境-陆相环境的转变;在须四早期,受安县运动的影响,龙门山褶皱成山,使研究区与阿坝海域完全隔绝,整个四川盆地真正进入了陆相沉积环境.     

A new discovery of macroscopic fossils from the Ediacaran Doushantuo Formation in the Yangtze Gorges area

The Ediacaran section in the Yangtze Gorges area, South China, is one of the most important in the worldand contains abundant fossils[1-4]. The earliest discov- ery of macrofossils in 1984, including macroscopic algal fossils from the uppermost Doushantuo…     

Discovery of the budding phosphatized globular fossils from the Neoproterozoic Doushantuo Formation at Weng’an, Guizhou Province, China

There is much debate on biological affinities of the phosphatized globular fossils from the Neoproterozoic Doushantuo phosphorites at Weng’an, Guizhou Province. Here we report for the first time the budding structures of some of these globular fossils, which have previously been interpreted as the resting eggs and early cleavage embryos of metazoans. The budding structures are similar to the germinating tubes of the spore and zygote of living algae, suggesting that some globular fossils from the Doushantuo phosphorites bear affinity with algae. The present new information indicated various biological affinity of the phosphatized globular fossils from the Doushantuo phosphorites.     

渤中凹陷地震-沉积相研究

主要应用地震 -沉积相的工作方法研究了渤海湾盆地老第三纪地层发育及地震相的特点 ,解释地震剖面 ,并转化为沉积相 ,在此基础上对油气勘探的有利区带作出预测。研究工作强调了地质模型的作用 ,并用岩芯的资料及单井的沉积相分析来约束地震解释。指出地质模型约束地震解释 ,是克服地震多解性、提高解释精度的有效方法 ,更好地发挥地震横向预测的作用。地质模型主要据“四扇一沟”的模式来构建 ,其依据是在渤海湾的沙河街组及东营组 ,其储层砂体主要是由在深湖条件下 ,在凸起的边缘上 ,往往有扇三角洲、三角洲、湖底扇组成 ,它们的分布区 ,往往就是油气勘探的有利区。研究发现 ,区内凡是凸起边缘若发育了断层 ,就有可能促使湖底扇的发育。在渤中的老第三系 ,浊流比较发育 ,因而 ,浊流砂体的预测就成为非常重要的课题     

鄂尔多斯盆地早侏罗世富县期冲积扇沉积

在综合研究野外露头、钻井剖面及室内编图、地层对比的基础上 ,指出鄂尔多斯盆地冲积扇 -河流沉积体系是侏罗纪富县期主要的古地理格局 ,富县期沉积受与古地貌密切相关的五条河谷控制。认为鄂尔多斯盆地侏罗纪富县期冲积扇沉积具进积型特征 ,其形成与古地形密切相关 ,分布于古甘陕、庆西河谷内     

胜利油田孤东矿区老第三系沙河街组辫状河三角洲沉积

胜利油田孤东矿区老第三系沙河街组中发现丰富的湖泊辫状河三角洲沉积物 ,其特征显著 ,明显有别于其他类型的三角洲 ,可见到 8种特征各异的微相。辫状河三角洲的主体为辫状河道砂坝及水下分流河道砂坝 ,单一河道砂坝呈透镜状 ,由含砾砂岩及中、粗粒砂岩组成向上变细层序 ,常见多个河道砂坝在纵向上互相叠置。三角洲中交错层理丰富 ,其中尤以水道砂坝侧向迁移加积而形成的侧积交错层发育为标志。在上述基础上 ,归纳总结了辫状河三角洲的鉴别标志 ,这对于在其他地区鉴别辫状河三角洲沉积具有意义。     

Further support for a Cretaceous age for the feathered-dinosaur beds of Liaoning,China:New 40Ar/39Ar dating of the Yixian and Tuchengzi Formations

We report new 40Ar/39Ar dating results obtained from total fusion and incremental-heating analyses of sanidine and biotite from three tuffs found interbedded within the fossil-bearing deposits of Liaoning, northeast China. The first is a new sample of the Bed 6 Sihetun tuff from the Yixian Formation, previously dated by our team as middle Early Cretaceous, and recently considered by Lo et al., partially reset due to metamorphism from a nearby basaltic sill. The second is the Yixian Bed 9 tuff from Hengdaozi considered by Lo et al. to be unaffected by metamorphism and whose age, based on total fusion 40Ar/39Ar dating of biotite, argues for a Jurassic age for the Yixian Formation.The third tuff is a previously undated tuff from the upper part of the underlying Tuchengzi Formation. Single crystal total fusion 40Ar/39Ar analyses of the Sihetun sanidine showed homogeneous radiogenic Ar, Ca/K ratios, excellent reproducibility and gave a mean age of 125.0 ± 0.18 (1SD) ±0.04 (SE) Ma. Single sanidine crystal total fusion 40Ar/39Aranalyses of the Hengdaozi tuff gave a mean age of 125.0 +0.19 (1SD) ± 0.04 (SE) Ma, which is indistinguishable from the Sihetun tuff. The Tuchengzi Formation tuff gave a mean age of 139.4 ± 0.19 (1SD) ± 0.05 (SE) Ma. Detailed laser incremental-heating analyses of biotite from Sihetun, Hengdaozi, and Tuchengzi tuffs show disturbed Ar release patterns and evidence of trapped argon components. We conclude from these analyses that the total fusion dates on biotite by Lo et al. are erroneously old and isotopic dating of both biotite and sanidine from tuffs of the Yixian Formation point to a middle Early Cretaceous age. The upper part of the Tuchengzi Formation can be referred to the Early Cretaceous.``