海拉尔盆地贝中地区南一段富含火山物质储层非均质性研究

The Research about Heterogeneity of Reservoir Rich in Volcanic Material of the First Member of Nantun Formation in Beizhong Area, Hailar Basin

摘要: 本文根据岩心观察、薄片鉴定、测井资料等，分析了海拉尔盆地贝中地区南一段富含火山物质储层非均质性，并对储层宏观非均质性和微观非均质性分别展开研究。结果表明，贝中地区南一段储层整体非均质性较强，其中南一段I~III油组非均质性中等，Ⅳ油组非均质性最强。宏观上，南一段各小层内砂体在平面上分布极为不均，储层参数在纵向上呈韵律性变化，自下而上单层平均砂厚有变薄的趋势，隔层发育及其分布具有较强的差异性，且南一段砂岩在平面上砂厚分布不均，孔、渗变化较大，具有较强的平面非均质性。微观上，南一段储层孔隙以次生溶孔为主，微观孔隙结构主要为超低渗，Ⅳ油组的储集性能优于I~III油组。沉积作用和火山活动是形成非均质性的主要控制因素。

Abstract: According to core observation, thin sections identification and logging data, this paper analyzes the reservoir heterogeneity in the first member of Nantun Formation in Beier Sag. The reservoir heterogeneity has been investigated on the macro and micro, and the results show that the reservoir has strong heterogeneity. In K1n1, the heterogeneity of Ⅳ oil group is the strongest while the other oil groups are medium. Macroscopically, each small layer sand body in plane distribution is extremely uneven. On the one hand, the reservoir parameters showed rhythmic variation in the vertical direction, and the average thickness of sandstone decreases from top to bottom. On the other hand, the interlayer development and distribution of these layers are very different. Furthermore, the thickness of the sand is uneven, and the porosity and permeability change greatly, showing strong plane heterogeneity. Microscopically, the porosity of reservoir is mainly secondary dissolution pore, and the micro pore structure is mainly ultra-low permeability. The reservoir performance of the IV oil group is higher than that of the I to III. Sedimentation and volcanism are the main controlling factors for the formation of heterogeneity.