塔里木盆地西南地区古近系层序地层及沉积相研究

发布时间：2018-08-23 11:48

【摘要】：本文研究区为塔里木盆地西南地区,共包括喀什坳陷、莎车隆起、叶城-和田坳陷及麦盖提斜坡等四个二级构造单元。研究的目的层为古近系,分为古新统、始新统、渐新统,包括吐依洛克组、阿尔塔什组、齐姆根组、卡拉塔尔组、乌拉根组和巴什布拉克组。根据论文研究内容,以多学科理论为指导,结合国内外层序地层研究现状,在仔细分析薄片、岩芯、钻井、测井、岩性组合等资料的基础上,深入研究目的层的岩石类型、沉积环境、沉积相及层序地层的关系,预测研究区有利储集相带。塔西南地区古近系深受喜山早期运动和喜山中-晚期运动的影响,喜山早期运动发生在白垩纪晚期,喜山运动中-晚期发生在古近纪渐新世末期。塔西南古近系古新统-始新统晚期海平面开始大规模上升,气候相对潮湿,研究区发育有障壁滨岸以及受海水盐度控制的开阔台地、局限台地和蒸发台地沉积体系;始新统晚期,伴随大规模全球海平面造成海退,研究区发育冲积扇—扇三角洲—湖泊相沉积体系。以层序地层学为理论基础,结合研究区沉积背景、岩石地层、地震地层综合分析,塔西南地区古近系共识别出二级层序界面2个:SSB1,SSB2,三级层序界面6个:SB2-SB7。在过井剖面和地震相研究的基础上,进行层序格架内沉积相展布及其主控因素研究,确立研究区层序沉积演化模式。最终编制沉积相平面图,并揭示沉积相展布规律。塔西南古近系层序形成主控要素有构造沉降、海平面变化及古气候条件。构造运动对层序的控制主要表现在对层序界面和对沉积古地貌的影响;海平面的升降控制着三级层序界面的形成与层序内部体系域的演化;古气候的变化则影响着碳酸盐岩台地类型和台缘位置的变迁。综合层序、沉积、储层特征分析认为,塔西南古近系主要有利储集相带为SQ4(卡拉塔尔组)开阔台地台内滩颗粒灰岩、云岩储集体。储集空间以粒间(溶)孔、粒内(溶)孔及铸模孔、生物骨架孔和晶间(溶)孔等次生孔隙为主。
[Abstract]:The study area is southwest of Tarim Basin, which consists of four secondary tectonic units: Kashi Depression, Shaqa uplift, Yecheng-Hetian Depression and Maigeti slope. The target layer is Paleogene, which is divided into Paleocene, Eocene and Oligocene, including Tuiluo formation, Altash formation, Zimgen formation, Karattar formation, Ulagen formation and Bashburak formation. According to the research content of the paper, under the guidance of multi-disciplinary theory, combined with the present situation of sequence stratigraphy research at home and abroad, on the basis of carefully analyzing the data of thin slice, core, drilling, logging and lithology combination, the rock types of the target layer are studied in depth. The relationship between sedimentary environment, sedimentary facies and sequence stratigraphy is used to predict the favorable reservoir facies zone in the study area. The Paleogene in southwest Tarim was influenced by the early Himalayan movement and the mid-late Himalayan movement. The early Himalayan movement occurred in the late Cretaceous and the mid-late Himalayan movement occurred at the end of the Oligocene Paleogene. The sea level began to rise on a large scale in the late Paleocene and the late Eocene in the southwest of Tarim Basin, and the climate was relatively humid. The study area developed barrier shoreline and open platform controlled by the salinity of sea water, limited platform and evaporation platform sedimentary system. In the late Eocene, the alluvial fan-delta-lacustrine sedimentary system was developed in the study area following the large-scale global sea level regression. Based on sequence stratigraphy, combined with sedimentary background, lithostratigraphy and seismostratigraphic comprehensive analysis in the study area, the Paleogene in southwest Tarim area has identified two secondary sequence interfaces (2: SSB1 / SSB2) and six third-order sequence interfaces (6: SB2-SB7). Based on the study of cross well profile and seismic facies, the distribution of sedimentary facies in sequence framework and its main controlling factors are studied, and the evolution model of sequence deposition in the studied area is established. Finally, the sedimentary facies plane map is compiled, and the distribution law of sedimentary facies is revealed. The main factors controlling the formation of Paleogene sequence in southwest Tarim are tectonic subsidence, sea level change and paleoclimate condition. The influence of tectonic movement on sequence interface and sedimentary paleogeomorphology, the rise and fall of sea level control the formation of third-order sequence interface and the evolution of internal system tract of sequence. Paleoclimate change affects carbonate platform type and the change of platform margin position. Comprehensive sequence, sedimentary and reservoir characteristics analysis shows that the main favorable reservoir facies belt of Paleogene in southwest Tarim is SQ4 (Karatar formation) open platform flat granular limestone and dolomite reservoir. The reservoir space is mainly composed of intergranular (dissolved) pore, intragranular (dissolved) pore and mold pore, biological skeleton pore and intergranular (dissolved) pore.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.13

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