鄂尔多斯盆地演武西地区侏罗系沉积储层特征研究

发布时间：2018-08-24 20:04

【摘要】：侏罗系储集层是鄂尔多斯盆地中生界主力油层之一,该层位具有储层物性好、饱和压力低、油藏规模小、储量丰度高、单井产量高的特点,但同时存在相对低渗低压以及油藏类型复杂等难题。本论文在前人研究基础上,结合大量野外和室内工作,对演武西地区侏罗系地层发育特征、古地貌的恢复、沉积相类型、储层特征和控制因素等方面进行深入研究。在地层划分对比的基础上,运用前侏罗系古地质图法、井震结合法以及地层厚度印模法对侏罗系延10沉积前古地貌进行刻画,其总体呈现出高地、残梁(丘)、斜坡、河谷、河间丘并存的面貌。通过对相标志的系统分析,确定了研究区的沉积相类型,演武西地区侏罗系主要发育辫状河及湖泊三角洲平原沉积。受西南物源影响,研究区的砂体总体呈现南西一北东方向延伸,沉积相带在平面上基本呈带状展布。通过对岩心样品进行分析,并对常规岩石薄片、铸体薄片的扫描电子显微镜镜下观察,对储层特征及储层发育控制因素进行研究,并对储层进行综合性评价。延安组延6~延10层储集岩岩石类型主要为中粒砂岩,岩屑含量以变质岩岩屑为主,填隙物主要为杂基和胶结物,砂岩的储集空间主要是孔隙,以剩余粒间孔为主。孔隙结构主要发育中低排驱压力-中粗喉型储集层,分选好-较好,属于中等-优质型储层。在以上研究的基础上,深入分析了储层发育的主控因素,主要受沉积作用、物质组分及成岩作用因素的影响,沉积微相的发育受不同水动力和沉积方式的控制;储集砂体以中粒砂岩为主,石英和岩屑含量较高,杂基相对较少;压实作用很大程度上减小孔隙度进而影响储层物性;胶结作用是孔隙减少的原因之一;溶蚀作用是改善物性的主要原因;交代作用形成自生高岭石的过程中也可改善物性;最后对研究区储层进行了综合评价,延6~延10段总体为II~III类储层,部分为Ⅰ类储层。
[Abstract]:Jurassic reservoir is one of the main reservoirs of Mesozoic in Ordos Basin. It has the characteristics of good reservoir physical property, low saturation pressure, small reservoir size, high reserves abundance and high single well production. But at the same time, there are some problems such as relatively low permeability and complex reservoir types. On the basis of previous studies, combined with a large number of field and laboratory work, this paper makes a thorough study on the characteristics of Jurassic strata development, paleogeomorphology recovery, sedimentary facies types, reservoir characteristics and controlling factors in Yanwu West area. On the basis of stratigraphic division and correlation, the paleogeomorphology of Jurassic Y10 was depicted by using the method of pre-Jurassic paleogeographic map, well and earthquake combination method and formation thickness impression method, which showed high ground, residual beam (mound), slope, valley, etc. The coexistence of the hills of the river. Based on the systematic analysis of the facies markers, the sedimentary facies types in the study area are determined. The Jurassic in the west Yanwu area is mainly composed of braided rivers and lake delta plain deposits. Under the influence of the southwest provenance, the sand bodies in the study area are generally extending from the south, west to the north, and the sedimentary facies belts are basically zonal distribution on the plane. Based on the analysis of core samples and the scanning electron microscope (SEM) observation of conventional and cast thin sections, the reservoir characteristics and controlling factors of reservoir development are studied, and the reservoir comprehensive evaluation is carried out. The reservoir rock types of Yan'an formation from 6 to 10 reservoirs are mainly medium-grained sandstone, with metamorphic lithic rocks as the main content, intergranular pore as the main reservoir space and residual intergranular pore as the main interstitial material. The pore structure is mainly developed in low and middle displacement pressure-coarse throat reservoirs, which are well sorted and good, and belong to medium-high quality reservoirs. On the basis of the above research, the main controlling factors of reservoir development are deeply analyzed, which are mainly influenced by sedimentation, material composition and diagenesis, and the development of sedimentary microfacies is controlled by different hydrodynamics and sedimentary methods. The reservoir sand body is dominated by medium grain sandstone, with high quartz and lithic content and relatively less complex base, compaction reduces porosity to a great extent and then affects reservoir physical properties, and cementation is one of the reasons for the decrease of porosity. Dissolution is the main reason for the improvement of physical properties, and the metasomatism can also improve physical properties during the process of forming authigenic kaolinite. Finally, the reservoir in the study area is evaluated synthetically. The reservoir of Y6 ~ Y10 is II~III type reservoir, part of which is type I reservoir.
【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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