鄂尔多斯盆地安边—新安边地区长6油层组成藏特征研究

发布时间：2018-12-15 18:26

【摘要】：安边-新安边地区位于鄂尔多斯盆地次级构造单元伊陕斜坡的中西部,长6油层组是该区主要的勘探层位,目前已发现许多规模油藏,但研究区不同区块不同层位上油气富集差异明显。本论文在充分吸收前人研究成果的基础上,以石油地质学、现代油气成藏理论为基础,综合应用大量分析化验资料来分析研究区油气成藏条件和油气富集差异原因,建立成藏模式,总结油气成藏主控因素,为研究区下一步的油气勘探与开发提供良好的导向。本文应用储层地质学、沉积岩石学和测井地质学的理论和方法对研究区的储层特征和砂体展布特征进行了系统的分析和研究。结果表明：研究区长6岩石类型主要为灰色细粒长石砂岩和岩屑长石砂岩,储集空间以粒间孔和长石溶孔为主,此外发育有少量裂缝。长6孔隙度主要分布在6～18%范围,渗透率主体分布在小于0.1～3×10-3μm2范围,纵向上长63的物性最差,长62次之,长61的物性最好；平面上安边地区的物性好于新安边地区。长61砂体最发育,厚度较大,沿物源方向砂体横向稳定性好；其次是长62,规模较长61小,存在多套砂体叠置,在部分区域也具有一定的连通性；长63规模最小,横向连通性最差。现今勘探成果表明新安边地区在长61、长62和长63原油均较富集,而安边地区仅在长61较富集,长62和长63基本无显示。通过油源对比指出研究区长6原油主要来自于下伏长7烃源岩的供给,长6自身泥岩供烃的贡献有限；通过长7泥岩分布图得出长7泥岩在新安边地区较发育,而在安边地区不发育；油气成藏的动力主要为泥岩欠压实作用产生的异常高压和生烃增压；裂缝在新安边地区较发育,而在安边地区不发育。综上得出新安边地区成藏为下伏长7烃源岩产物垂向运移到长6储层,裂缝是新安边地区成藏的关键；安边地区成藏是新安边地区长61中的原油侧向运移过去的,砂体连通性、物性和单斜构造是安边地区成藏的关键。总结研究区油气成藏的主控因素主要有以下几方面：烃源岩分布、裂缝分布、储层物性、砂体展布和单斜构造。
[Abstract]:The Anbian-Xin 'anbian area is located in the central and western part of the Yishan slope of the secondary structural unit of the Ordos Basin. The Chang 6 oil formation is the main exploration horizon in this area. At present, many large reservoirs have been discovered. But there are obvious differences in hydrocarbon enrichment between different formations in different blocks in the study area. Based on petroleum geology and modern oil and gas accumulation theory, this paper uses a large amount of analytical and laboratory data to analyze the conditions of oil and gas accumulation and the reasons for the difference of oil and gas accumulation in the study area, on the basis of fully absorbing the previous research results and based on the theory of petroleum geology and modern oil and gas accumulation. The model of oil and gas reservoir formation is established and the main controlling factors of oil and gas accumulation are summarized, which provides a good guide for the further exploration and development of oil and gas in the study area. Based on the theories and methods of reservoir geology, sedimentary petrology and logging geology, this paper makes a systematic analysis and study on the reservoir characteristics and the distribution characteristics of sand bodies in the study area. The results show that the main rock types of Chang 6 in the study area are gray fine-grained feldspar sandstone and lithic feldspar sandstone with intergranular pore and feldspar dissolution pore as the main reservoir space and a small number of fractures. The porosity of Chang 6 is mainly distributed in the range of 6 ~ 18%, the main distribution of permeability is in the range of less than 0.1 脳 10 ~ (-3) 渭 m ~ (2), the physical property of longitudinal length 63 is the worst, Chang62 is the second, and Chang61 is the best. The physical properties of Anbian area on the plane are better than that of Xinanbian area. Chang 61 sand body is the most developed, the thickness is large, the transverse stability of sand body is good along the direction of material source, the second is long 62, the scale is longer 61 small, there are many sets of sand bodies overlay, also have certain connectivity in some areas. The length of 63 is the smallest, and the horizontal connectivity is the worst. The present exploration results show that Chang61, Chang62 and Chang63 are enriched in Xinanbian area, but only in Chang61, Chang62 and Chang63 in Anbian area. The oil source correlation indicates that Chang 6 crude oil in the study area mainly comes from the supply of source rock of Lower potential Chang 7, and the contribution of mudstone of Chang 6 itself is limited. According to the distribution map of Chang7 mudstone, Chang7 mudstone is relatively developed in Xinanbian area, but not developed in Anbian area, the main motive force of oil and gas accumulation is abnormal high pressure and hydrocarbon generating pressure caused by undercompaction of mudstone. The cracks are relatively developed in Xinanbian area, but not in Anbian area. It is concluded that the reservoir formation in Xinanbian area is the vertical migration of hydrocarbon products from source rock of Lower potential Chang 7 to Chang 6 reservoir, and the fracture is the key to reservoir formation in Xinanbian area. The reservoir formation in Anbian area is the lateral migration of Chang61 crude oil in Xinanbian area. Sand connectivity, physical property and monoclinic structure are the key factors for reservoir formation in Anbian area. The main controlling factors of hydrocarbon accumulation in the study area are summarized as follows: distribution of source rocks, distribution of fractures, reservoir physical properties, distribution of sand bodies and monoclinic structures.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13

【参考文献】