【作者】 卢山；

【导师】 蒲仁海；

【作者基本信息】 西北大学 ， 矿产普查与勘探， 2011， 硕士

【摘要】 志丹西区采油厂油区位于伊陕斜坡中西部,区内主要包括寨科区、旦八区和义吴区,产层主要有延长组和延安组油层,属于岩性圈闭,是典型的特低渗油田。本次研究以旦八区南部长4+5砂岩储层为对象,通过对地层沉积相规律、砂体展布规律、储层特征及其影响因素等方面展开深入而细致的研究,最终取得了以下几方面的成果和认识：1、本文结合旦八地区岩心观察描述、目的层段岩石薄片、测井资料及前人对本区的地质研究等资料,将延长组长4+5油层组分为长4+5上和长4+5下两个油层段。2、旦八油田区域构造表现为西倾斜坡构造,研究区长4+5油层组各个小层都发育有近东西走向的鼻状凸起,其成因主要为差异压实作用,并受构造挤压应力影响；构造走向与砂体走向斜交,为形成岩性油藏提供了有利条件。3、旦八区油层段分布稳定,各井间岩性～电性组合特征具相似性,厚度展布较一致。长4+5下砂岩在厚度及连片性方面均优于长4+5上。4、沉积相带展布以近南北向或北北东～南南西向为主,长4+5下油层段优势相带为水下分流河道微相区,反映砂岩整体连片性好,砂岩含量高的特点。长4+5上沉积相展布特征表明砂岩含量明显减少,其砂岩东西向连片性较差。5、岩矿特征分析表明,储集层砂岩类型以长石砂岩为主；填隙物主要由胶结物及杂基组成,其中胶结物多为绿泥石、伊利石等自生粘土矿物及石英次生加大。长4+5油层组砂岩在成岩过程中经历了不同程度的压实作用、胶结作用、交代作用及溶蚀作用。6、孔隙类型分为原生孔隙和次生孔隙。储层的发育程度与孔隙类型分布密切相关。按旦八区南部长4+5油层组砂岩的岩性、物性、砂体展布特征等因素,将本区砂岩储层划分为Ⅰ、Ⅱ、Ⅲ类。更多还原

【Abstract】 The Xiqu oilfield of Zhidan area is located in the middle of Yishan slope, which contains Zhaike area, Danba area and Yiwu area. Yanchang formation and Yanan formation, which belong to lithologic reservoir, are the two important oil-bearing series, and they are typical extra-low permeable oilfield. In this research, the Chang 4+5 reservoir of southern Danba area is regarded as main research object, through the depth and detailed study on the method of sedimentary facies and sand body distribution, reservoir characteristics and its effect factors, we finally obtained the following results and understanding of several aspects:1. Combined with core observation, sheet rock of pupose layers, log data and other comprehensive information in Yishan slope, Chang 4+5 oil layer can be divided into upper Chang 4+5 oil member and lower Chang 4+5 oil member.2. The regional tectonic of Danba oilfield performances as west dipping monocline form. Each small layer of Chang 4+5 reservoir group develops nose shape uplift structure of nearly east-west trend, which caused by the differential compaction and the influence of tectonic compression; The oblique-crossing between structure trend and sand trend provides favorable conditions for the formation of lithologic reservoir.3. The oil sections of Danba area distribute stability, and lithologic and electrical property during different wells shows similarity. The sandstone of lower Chang 4+5 is better than upper Chang 4+5 in aspects of thickness and contiguous.4. Distribution of sedimentary facies mainly appears south-north or northeast-southwest trend, the sand body of underwater distributary channel were oil reservoir group of lower Chang 4+5, which show good contiguous of the entire sands and high sandstone content. The distribution of sedimentary facies of upper Chang 4+5 shows that the sandstone content decreased sharply.5. On the base of lithologic characteristics, the detrital composition of reservoir are mainly composed of quartz and feldspar, secondly are cuttings; Interstitial material are mainly composed of cement and miscellaneous base, and cements are mainly chlorite, illite and other antigenic clay mineral and quartz overgrowth. Types of diagenesis include mechanical compaction, cementation, metasomatism and dissolution.6. Pore types can be divided into primary pores and secondary pores. The degree of reservoir’s development is closely related with the distribution of pore types. According to the lithology, physical properties, characteristics of sand distribution and other factors of southern Danba region, sandstone reservoirs in this area can be divided intoⅠ,Ⅱ,Ⅲclass.更多还原