【作者】 张春明；

【导师】 姜在兴；

【作者基本信息】 中国地质大学(北京) ， 矿产普查与勘探， 2012， 博士

【摘要】 临南地区是指惠民凹陷夏口断层以北、营子街断层以南的地区，是临南洼陷油气运移的有利指向区和富集区，勘探面积约1000km2。随着研究区勘探开发进程，深层沙三下亚段将成为油田下阶段勘探的重点。论文以临南地区古近系沙三下亚段为研究对象，运用层序地层学、沉积学、储层地质学等理论方法，以钻井、测井资料和相关分析测试数据为基础，运用理论研究与实际研究相结合，宏观研究与微观研究相结合的技术思路，系统研究了临南地区古近系沙三下亚段的层序地层特征、沉积相特征和储集性能特征。将沙三下亚段划分为二个层序。层序一发育低位、湖侵和高位三个体系域，低位体系域划分为三个准层序组，湖侵体系域划分为二个准层序组，高位体系域划分为四个准层序组；层序二在研究层位仅发育低位体系域，划分为五个准层序组。在层序地层格架内，对沙三下亚段进行了沉积相的详细分析，层序一时期，湖盆处于初始发育阶段，水体不稳定，发育洪水-漫湖沉积体系，识别出了泥坪、砂坪、砂泥混合坪和洪水水道四种微相；层序二时期，湖盆趋于稳定，发育了三角洲前缘和下切谷沉积，细分为水下分流河道、河口砂坝、远砂坝、分流间湾、下切谷水道、水道天然堤和水道间漫溢七种微相。有利砂体主要发育于层序一的砂坪微相、洪水水道微相，层序二的三角洲前缘水下分流河道微相、河口砂坝微相、远砂坝微相和下切谷水道微相。砂坪砂体和三角洲前缘砂体连片性好，水道砂体限制性发育，为孤立条带状。结合研究区实际情况，根据岩石薄片、铸体薄片、扫描电镜、压汞分析等资料，对研究区砂体的储集性能及其控制因素进行了研究。沙三下亚段地层主要以岩屑长石砂岩和长石砂岩为主，胶结类型以孔隙式和镶嵌式为主，成岩作用类型比较丰富，对储集性能影响较大。储集空间主要有原生粒间孔、粒内溶孔、粒间溶孔、铸模孔、胶结物内溶孔、次生加大胶结物晶间孔、颗粒贴粒缝和构造裂缝等8种，主要以次生孔隙为主。结合岩石物性和毛管压力曲线等分析测试数据，对其物性进行综合评价，认为沙三下亚段地层孔隙度渗透率非均值系数大，非均质性较强。砂体储层储集性能主要受到沉积微相和成岩作用控制。沉积微相主要控制砂岩岩性类型，分为细粒碎屑沉积和粗粒碎屑沉积。成岩作用对细粒沉积的控制作用比较强，压实压溶作用及砂岩层顶底钙质胶结作用降低储层孔隙度，导致储集性能的差异，而溶蚀作用提高储层孔隙度，使得物性得以改善。粗粒沉积储集性能的差异主要受杂基含量控制，杂基支撑砂体储集性能差，颗粒支撑砂体储集性能比较好。此次研究对于该地区的进一步勘探开发具有重要的理论意义及现实指导意义。更多还原

【Abstract】 The Linnan region, located in the north of Xiaokou fault and the south of Yingzijiefault, is the favorable migration and accumulation district in Linnan sag. The totalexploration area is approximately 1000km2. With the development of exploration, thelower part of the third member of Paleogene Shahejie Formation is gradually becomingthe key point. In this article we focus on the study of the sequence stratigraphy,sedimentary facies and reservoir characteristics of the lower part of the third member ofPaleogene Shahejie Formation based on cores, well-logs, and formation test dataincluding the thin sections and cast thin sections, observation of scanning electronmicroscope (SEM), pressured-mercury testing and X-ray diffraction analysis of clayminerals.The stratum of the lower part of the third member of Paleogene Shahejie Formationcan be divided into two sequences. Sequence one can be further divided into threesystems tracts: the lowstand systems tracts composed of three parasequence sets, thetransgressive systems tracts composed of two parasequence sets and the highstandsystems tracts composed of four parasequence sets. Sequence two only has the lowstandsystems tracts which consist of five parasequence sets in the target layer. Within thesequence stratigraphic framework, the sedimentary facies are studied. Sequence one, thelake was in the initial development stage and the water body was unstable. Theflood-overlake depositional system, involving the mud flat, sand flat, mixing flat and theflood channel mainly developed. Sequence two, the lake basin became more stable, thesedimentary facies changed to the delta front and incised valley in which containedmicrofacies of the underwater distributary channel, the channel mouth bar, the distal bar,the interdistributary estuary, the incised valley channel, the channel levee and the channeloverflowing. The favorable sand mainly deposited in microfacies of the sand flat and theflood channel in sequence one and the underwater distributary channel, the channelmouth bar and the distal bar in delta front and incised valley channel in sequence two. Onthe contrary with the isolated channel sand strips, the sand body deposited in sand flatand delta front displayed good continuous distribution. The reservoir characters and its controlling factors were also researched using thinsections, SEM, mercury intrusion and so on. Lithic feldspathic and feldspathicsandstones are chief rock types in the study area. The main cementation types are theporous cementation and mosaic cementation and the diagenesis had a magnificent impacton reservoir properties. Eight pore types including primary intergranular pores, theintragranular dissolved pores, the intergranular dissolved pores, the molded pores, thecement dissolved pores, the overgrowth quartz intergranular pores, the gaps along theparticles and microfractures are identified in the target layer. The secondary pores are themain pore type. By analyzing physical materials, it can be seen that the porosity andpermeability had strong heterogeneity. In general, reservoir physical properties are underthe control of the microfacies and the diagenesis. The influence of the sedimentarymicrofacies primarily reflected on the controlling of the lithological type, involving thefine-grained clastic sediments and the coarse-grained clastic deposition. For thefine-grained clastic reservoir, it is mainly controlled by the diagenesis. The calcareouscementation of the sandstone’s top and bottom result the reservoir heterogeneity andreduce the porosity and permeability. Whereas the dissolution can increase the reservoirporosity and make reservoir properties improved. For the coarse-grained clastic reservoir,the matrix content is the main controlling factors. The matrix-supported channelsandstones display bad properties, and the grain-supported sandstones are better. All inall, the whole research has an important theoretical and guiding significance for thefurther exploration and development of the study area.更多还原