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山东沂水地区早中寒武世地层属陆表海沉积。岩性组合，沉积旋回，岩相，相序以及地层结构，层序界面标志等特征，将区内中下寒武统划分９个层序和识别出１０个层序界面。Ⅰ型和Ⅱ型层序上海侵体系域和高水位体系域组成，凝缩段不甚发育。 相似文献
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贵州东部中新元古代沉积旋回的划分 总被引：2，自引：0，他引：2
应用层序地层学及事件地层学的概念和方法,从沉积旋回的研究入手,首次在该区出露的中、新元古代地层中划分出４个不同级别的旋回层（或层序）,即（从老到新）梵净山群１个（相当于１个一级层序）、下江群１个（相当于１个一级层序）、震旦系２个（即铁丝坳组－大塘坡组和南沱组－灯影组,相当于２个二级层序）。同时对上述所划层序界面、初始海泛面、凝缩层（其中包含量大海经泛面）及沉积体系城的特征作了归纳性描述。另外还分析 相似文献
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应用活动观点划分麻粒岩相，高角闪岩相和低角闪岩相３个地层区。将全省太古宙地层划分为子岭片麻岩，变质火山－沉积岩系，面型英云闪长质－花岗闪长质片麻岩，ＴＴＧ型高位侵入岩套和花岗岩等５大套岩石地层，并按基本岩石地层单位建立地层序列表，对太古宙一早元古代壳运行和主要构造事件，多期变质作用等进行论述，划分出三期褶被，三期韧性剪切带，提出区域性递增变质带新概念，论证了安子岭片麻岩是最古老的的陆壳。 相似文献
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内蒙古苏尼特左旗地区二叠纪地层的划分与对比 总被引：5，自引：0，他引：5
本文讨论了内蒙古苏尼特左旗地区二叠纪地层单元的划分及其接触关系，认为本区二叠纪地层应包含大石寨组与哲斯组，缺失晚二叠世沉积；描述了代表本区地层序列演化的典型剖面，并对各单位在区域上的延伸及其对比关系进行了简述，认为本区二在纪地层的区域对比应以火山事件沉积为主线，以地层序列演化及生物化石为标志，而不应以岩性相及厚度为主要依据；根据区域地层序列演化分析，认为大石寨组与哲斯组之间的不整合是本区构造事件的代表性界面。 相似文献
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陆表海盆地海侵事件成煤作用机制分析 总被引：29，自引：4，他引：25
研究了含煤地层中海侵事件沉积序列,即海侵沉积与煤层直接接触的组合特点,总结了海侵事件和海侵事件成煤特点,提出了陆表海聚煤盆地海侵事件成煤作用理论及海侵事件成煤机制。研究表明,陆表海盆地充填沉积序列中,既有海退成煤作用又有海侵成煤作用发生,而且,海侵事件为陆表海盆地海平面变化的典型特色,海侵的突发性是海侵事件的基本属性,其沉积具有等时性。海侵事件导致盆地事件型聚煤作用发生。本文还深入讨论了海侵事件成煤机制及其在含煤地层层序地层界面识别、层序地层单元划分的重要意义和作用。 相似文献
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根据事件地层学的发展现状,首次提出了一套系统的事件地层单位,由小到大大致上为事件面、事件层、事件带、事件组合和事件集群,并界定了各事件地层单位的含义和特征。在此基础上,将该套事件地层理论应用于中扬子台地震旦—寒武系界线事件地层的研究,并划分出2个事件面即生物灭绝事件面和海泛事件面,1个事件层即粘土事件层,4个事件带即海平面下降事件带、浊流事件带以及海平面上升事件带和缺氧事件带,3个事件组合即海平面下降—浊流事件组合、外星撞击—生物灭绝事件组合和海平面上升—缺氧事件组合,共同构成了1个事件集群即震旦—寒武系界线事件集群。事件地层含油性分析表明,研究区海平面上升—缺氧事件组合是有利的烃源岩,海平面下降—浊流事件组合具有一定的储集意义。 相似文献
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The object of this paper is the study of the Cretaceous deposits in the Mompichel area, Albacete (SE Spain) and to describe the lithostratigraphic units. In the same way the different species of spores and pollen are shown to occur in two levels belonging to unit D, which has allowed for the dating of these terrigenous deposits as Early Albian. 相似文献
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龙门山中南段四川大邑、崇州、都江堰、汶川地区，侏罗系、白垩系、第三系发育良好，划分为侏罗系白田坝组、千佛岩组、沙溪庙组、遂宁组、莲花口组及五龙沟砾岩一组至三组；白垩系天马山组、夹关组和灌口组；下第三系名山组和上第三系（上部包括部分第四系）的大邑砾岩等岩石地层单元。各个地层单元中几乎都有砾岩沉积。概述了该区砾岩的时空分布及特征，按沉积环境将砾岩划分为冲积扇砾岩、河道滞留砾岩及湖滨砾岩等，最后讨论了物源区及其时空演化。 相似文献
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The Lower Cretaceous series, in the Western Saharan Atlas, shows important detritic deposits, particularly continental to nearshore red sandstones. Lithologically, it is an alternation of red clay and sandstone intercalated with some carbonate levels at the lower part of the series. These series can be subdivided into three lithostratigraphic units corresponding to Valanginian-Hauterivian, Barremian, and Aptian-Lower Albian. The lithostratigraphic analysis used to reconstitute the important subsidence in the Lower Cretaceous period, particularly in the Lower Albian. The Lower Cretaceous series could be considered as a geodynamic model characterized by individualization of independent depocenter filled with different detritic material and separated by Jurassic structures. This new situation appeared in the beginning of Lower Cretaceous (Valanginian-Hauterivian), following the Neocimmeriean tectonic phase, and it is increasing in the Early Albian, where differences of thicknesses are more important and allow the distinction of the depocenter. The biostratigraphic analysis of the clay samples yielded some foraminifera and palynomorphs. Benthic and planktonic foraminifera confirmed the Hauterivian age of the basal formation, also, two dominant forms of palynomorphs were recognized; according to the large stratigraphic distribution of the identified forms, it can be attributed to the Lower Cretaceous. 相似文献
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燕山运动在浙江及华南各省普遍存在,对其阶段（期）的划分尚有一些分歧。近年对浙江省岩石地层单位及构造运动不整合面进行了清理,将中生代构造运动划分为５个阶段。建议把印支运动之后至白垩纪末期的地壳运动称为广义的燕山期,而把狭义的燕山运动置于白垩纪末期。 相似文献
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安徽合肥盆地东北部白垩纪层序地层学分析 总被引：3，自引：0，他引：3
运用层序地层学理论和工作方法 ,对合肥盆地东北部白垩纪陆相地层各类沉积建造的沉积环境、沉积相和陆相沉积体系域进行了分析 ,根据红层盆地的沉积物充填序列、基本层序 ,将白垩纪断 (坳 )陷盆地充填沉积序列中划分为 4个层序 ,在层序地层学分析基础上 ,并根据岩石地层单元和沉积体系在时空上的展布特征 ,初步建立了红盆地层格架。 相似文献
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介绍清理后的一个地层单位———龙潭组。江苏地层清理项目组以现代地层学理论为指导 ,经 3年多工作 ,搜集了江苏近 10 0年来大量新太古代至第三纪地层资料。以岩石地层为主与生物、年代地层等进行多重划分对比研究 ,从近 3 0 0个地层单位名称中 ,经清理筛选确定采用 10 5个岩石地层单位和 4个非正式岩石地层单位 ,重编了地层表 ,并建立了地层库 ,使江苏地层划分由统一划分发展到多重划分阶段。 相似文献
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《International Geology Review》2012,54(1):93-110
The origin and continuity of Phanerozoic lithostratigraphic terranes in southern and Baja California remain an unsolved issue in Cordilleran tectonics. We present data from eight detrital zircon samples collected across the southern extent of the Peninsular Ranges that help constrain the provenance of detritus and the depositional ages of these basement units. Detrital zircon signatures from units in the eastern Peninsular Ranges correlate with Palaeozoic passive margin assemblages in the southwestern North American Cordillera. Units in the central belt, which consists of Triassic–Jurassic metasedimentary turbidite assemblages that probably deformed in an accretionary prism setting, and Cretaceous metasedimentary and metavolcanic units that represent the remnants of a continental margin arc, were derived from both proximal and more distal sources. The westernmost units, which are locally structurally interleaved with the Triassic through Cretaceous units of the central belt, are Cretaceous deposits that represent a series of collapsed basin complexes located within and flanking the Cretaceous Alisitos volcanic island arc. Cretaceous intra-arc units show little influx of cratonal material until approximately 110 Ma, whereas coeval sediments on the northern and eastern flanks of the Alisitos arc contain abundant cratonal detritus. Intra-arc strata younger than approximately 110 Ma contain large amounts of Proterozoic and older detrital zircons. These data suggest that basins associated with the Alisitos arc were either too distant or somehow shielded from North American detritus before 110 Ma. In the case of the former, increased influx of continental detritus after 110 Ma would support a tectonic model in which the arc was separated from North America by an ocean basin and, as the arc approached the continent, associated depositional centres were close enough to receive input from continental sources. 相似文献