以云南曲靖地区筇竹寺组泥页岩为例,利用氩离子抛光-场发射扫描电镜、高压压汞、常规扫描电镜等实验技术手段,探究泥页岩储层微观储集空间的发育类型与特征。结果表明:筇竹寺组泥页岩储层孔隙成因复杂,类型多样,主要发育的微观储集空间类型包括有机质孔隙、粘土矿物孔隙、颗粒矿物孔隙、微裂隙等,以有机质孔隙最为发育,提供了主要的储集空间;孔隙度介于1.59%~11.33%之间,平均值达到了5.0%,小孔、微孔所占储集空间比例约56.5%,中孔和超大孔所占比例为34.0%,大孔相对较少。控制筇竹寺组页岩孔隙发育的因素主要有TOC、矿物组分和成岩作用,TOC是影响筇竹寺组页岩储层孔隙发育的主控因素,也是提供页岩气主要储存空间的重要物质。
Using mudstone and shale samples of the Qiongzhusi Formation in the Qujing area of Yunnan Province as an example, the types and characteristics of microscopic reservoir space of the shales were investigated by combined methods, including Argon ion polishing-field emission scanning electron microscopy (FESEM), high-pressure mercury injection and conventional scanning electron microscopy (SEM). Results show that the pores in shale samples of the Qiongzhusi Formation have complex formation mechanisms and different types including organic pores, clay mineral pores, grain mineral pores and microfratures, of which the organic pores dominate. The porosity is between 1.59%-11.33% with an average value of 5.0%. The reservoir space proportions of micro- and transitional pores are about 56.5%, mesopores and macropores are about 34.0%, while macropores are relatively undeveloped. TOC contents, mineral compositions and diagenesis are the main controlling factors for the development of shale pores in the Qiongzhu Formation. TOC is the main control for the development of shale pores in the Qiongzhu Formation.