伊通地堑莫里青断陷双阳组敏感性储层类型及其分布规律

SENSITIVE RESERVOIR TYPES AND DISTRIBUTION REGULARITY OF SHUANGYANG FORMATION IN MOLIQING FAULT DEPRESSION,YITONG GRABEN

莫里青断陷位于伊通地堑的西南部,是一呈北东向展布的狭长半地堑式断陷。其内发育的古近系始新统双阳组是研究区目前主要的产油层位,油气储层主要为近源堆积砂体,油井投产后产能变化急剧。大量实验测试数据分析表明,不同区带、不同埋深的双阳组储层中存在不同程度的中强碱敏性、中强酸敏性、中强水敏性及中强盐敏性,其主要分别受控于高岭石填隙物、碳酸盐胶结物、伊蒙混层及伊利石矿物的分布特征。根据影响各种敏感性的岩石矿物分布规律及敏感性机理综合研究,可将莫里青断陷双阳组储层区分为7种敏感性类型,不同敏感性储层类型在断陷中分布具有明显的规律性。断陷盆地中,储层砂体的粘土基质含量高,敏感性明显,敏感性储层类型分布规律的研究对油气勘探开发具有重要的经济意义。

Moliqing Fault Depression is situated in the southwest part of Yitong Graben, and is an elongatedsemi-graben that trends NE. So far, Shuangyang Formation of Eocene of Paleogene developed in this basin is the main oil production formation. Hydrocarbon reservoirs are mainly near source sandbodies, the productivities of oil wells that were put into production change greatly. A lot of experimental data analysis show that reservoirs of Shuangyang Formation in different zones and different buried depths have different degrees of moderately strong alkali sensitivity, acid sensitivity, water sensitivity and salt sensitivity, which are separately controlled by the distribution characteristics of kaolinite interstitial material, carbonate cements, the mixed layer of illite and montmorillonite, and illite. According to the distribution regularity of rocks and minerals that influence different kinds of sensitivities and comprehensive research on sensitivity mechanism, the reservoir areas of Shuangyang Formation in Moliqing Fault Depression are divided into 7 kinds of sensitivities, and the reservoir types with different sensitivities has obvious distribution regularity in the fault basin. In fault basin, the higher is the content of clay matrix in reservoir sandbody, and the more obvious the sensitivity will be. Research on distribution regularity of sensitivity reservoir types has an important economic significance to oil and gas exploration and development.