川西北中二叠统茅口组储层特征及成因

Characteristics and Origin of Reservoir of the Middle Permian Maokou Formation in Northwest Sichuan

对四川盆地西北部钻井岩心、露头剖面样品的宏观及微观岩石学特征研究认为,川西北茅口组储层类型主要为生屑灰岩,储集空间主要为生物格架孔、粒间溶孔、粒内溶孔、溶蚀孔洞及裂缝。茅口组储层的发育主要受到沉积微相、古岩溶作用及构造作用等因素控制。其中沉积微相是储层形成的物质基础,古岩溶作用是储层形成的关键因素,而构造裂缝是储层改善及连通的重要因素。

Petrographical study indicates that reservoir of the Middle Permian Maokou Formation in the northwest Sichuan Basin consists mainly of bioclastic limestone with organic framework pores, intergranular dissolved pores, intragranular dissolved pores, dissolved cavities and fractures as reservoir pore space. Development of the reservoir was mainly controlled by sedimentary microfacies, palaeokarst and tectonism.