大宁￣吉县地区盒8段储层特征及其控气作用

Reservoir characteristics and its gas control of He 8 Member in Daning-Jixian area

党佳城 赵靖舟 耳闯 任大忠

西安石油大学地球科学与工程学院，陕西 西安 710065 西安石油大学陕西省油气成藏地质学重点实验室，陕西 西安 710065 西安石油大学石油工程学院，陕西 西安 710065）

School of Earth Science and Engineering, Xi′an Shiyou University, Xi′an 710065, China Shaanxi Key Laboratory of Petroleum Accumulation Geology, Xi′an Shiyou University, Xi′an 710065, China College of Petroleum Engineering, Xi′an Shiyou University, Xi′an 710065, China

鄂尔多斯盆地大宁￣吉县地区致密气具有产气层系多、勘探潜力大的特点，但天然气富集主控因素多元，导致勘探部署方向或目标不明确。文中以大宁￣吉县地区二叠系盒8段为研究对象，利用钻井、测井、岩心、试气以及化验分析资料，分析储层特征，明确气藏类型及分布，探讨储层条件对致密气的控制作用。研究表明：盒8段储层以中、细砂岩为主，储集空间以残余粒间孔和溶蚀孔为主；孔隙度平均为7.1%，渗透率平均为0.39×10-3 μm2，属于致密储层；气藏类型为岩性致密气藏，具有纵向多层叠置、平面连片的“准连续型”分布特征；气藏分布受砂体厚度、砂岩泥质含量和储层孔隙结构、岩性、物性共同控制；储层厚度大、石英含量高、泥质含量低、物性好的储层有利于致密气富集。

The tight gas in the Daning-Jixian area of Ordos Basin is characterized by multiple gas producing strata and large exploration potential, but the main controlling factors for natural gas enrichment are diverse, leading to unclear exploration deployment. This paper takes Permian He 8 Member in the Daning-Jixian area as the research object, drilling, logging, core, gas testing and laboratory analysis data are used to analyze the characteristics of tight reservoirs, clarify the type and distribution of gas reservoirs, and explore the control effect of reservoir conditions on tight gas. The research shows that the reservoir of He 8 Member is mainly composed of medium and fine sandstones, and the reservoir space is mainly dominated by residual intergranular pores and corrosion pores. The average porosity is 7.1%, and the average permeability is 0.39×10-3 μm2, belonging to a tight reservoir. The type of gas reservoir is lithological tight gas reservoir, with a "quasi continuous" distribution characteristic of vertical multi-layer stacking and planar connection. The distribution of gas reservoirs is jointly controlled by sand body thickness, reservoir lithology, sandstone shale content and physical properties. Large reservoir thickness, high quartz content, low shale content and good physical properties are conducive to the formation of tight gas enrichment.

10.6056/dkyqt202304001