镇北长3段储层特征及主控因素研究

发布时间：2018-01-26 11:50

  本文关键词： 镇北油田 储层特征 成岩作用 胶结作用 主控因素　出处：《西安石油大学》2017年硕士论文　论文类型：学位论文

【摘要】：鄂尔多斯盆地镇北油田长3油层组油气丰富,建产区块较多,但砂体变化快,建产区块小,储层展布不够清晰,且储层储集性能的主控因素等方面的研究相对薄弱。因此,有必要开展长3储层特征及主控因素研究,为下一步勘探开发提供地质依据。本文以沉积学、储层沉积学及石油地质理论为指导,利用岩心观察、铸体薄片鉴定、X-衍射分析、扫描电镜、压汞测试等多种测试分析手段,对镇北地区长3油层组的储层岩石学特征、微观孔隙结构特征、成岩作用、物性特征等方面进行了综合研究,并得到以下结论。本区长3储层的结构成熟度中等,以灰色或浅灰色中细粒岩屑长石砂岩为主,填隙物分布不均,以硅质含量为主,其次为水云母。长3主要孔隙类型主要为剩余粒间孔,其次为长石溶孔。储层经历的成岩作用类型主要有:压实作用、胶结作用和溶解作用。胶结作用中主要为硅质胶结,其次水云母胶结。溶蚀作用是形成次生孔隙的主要作用。成岩相划分为I类中粗砂岩弱压实相、II类高岭石胶结溶蚀孔相、III类中细砂岩残余粒间孔相和Ⅳ类致密胶结相四类成岩相。成岩演化阶段主要处于晚成岩阶段的A期。本区物性特征研究表明:其中长31、长32和长33储层的平均渗透率分别为3.05×10~(-3)μm~2、3.21×10~(-3)μm~2、3.15×10~(-3)μm~2,储层的平均孔隙度分别为12.95%、12.84%、12.42%。渗透率主要是由于各小层之间的孔隙结构不同,长32的喉道半径最大。长3储层属于中低孔—超低渗类储层。从整体上来讲,本区长3储层主要受沉积相的控制,其次是成岩相。沉积相从宏观上控制着储层物性的分布,而且三角洲平原的物性好于三角洲前缘,整体上表现为分支河道和水下分流河道物性较好;分流河道中主要发育中粗砂岩弱压实相(水云母4,碳酸盐4,沉积相带粗)且物性最好,分布在Z291—Z299—Z448—Z231的西部。其次是水下分流河道中发育高岭石胶结溶蚀孔相(溶蚀孔相对含量40%)的储层物性,主要分布在桐川附近。
[Abstract]:Chang 3 reservoir formation of Zhenbei Oilfield in Ordos Basin is rich in oil and gas, and there are many blocks in the built-up area, but the sand body changes rapidly, the block is small, and the reservoir distribution is not clear enough. Therefore, it is necessary to study the characteristics and main control factors of Chang 3 reservoir to provide geological basis for further exploration and development. Under the guidance of reservoir sedimentology and petroleum geology theory, using core observation, casting thin section identification, X-ray diffraction analysis, scanning electron microscope, mercury injection test and other means of testing and analysis. The petrological characteristics, microscopic pore structure, diagenesis and physical properties of Chang 3 formation in Zhenbei area were studied. The results are as follows: the structure maturity of Chang3 reservoir in this area is moderate, mainly of gray or light gray medium fine grained lithic feldspathic sandstone, uneven distribution of interstitial material, and mainly siliceous content. The main pore types of Chang 3 are residual intergranular pores, followed by feldspar dissolution pores. The diagenesis types of reservoirs are mainly compaction. Cementation and dissolution. The cementation is mainly siliceous cementation, followed by hydromica cementation. Dissolution is the main role of forming secondary pores. Diagenetic facies can be divided into class I medium coarse sandstone weak compaction facies. Type II kaolinite cementation solution pore facies. There are four types of diagenetic facies: residual intergranular pore facies of III type and dense cementation facies of type 鈪，

本文编号：1465530