Reservoir fracture cave characteristics of middle - lower Ordovician carbonate rocks in Tahe oilfield in Tarim Basin, China

Abstract

Different carbonate types found in Tahe Oilfield and their petrological characteristics are analyzed. Primary rock types include sandy limestone, bamboo-like limestone, sandy limestone, dolomitic micrite, particle limestone, limestone containing organic matter, micrite, and siliceous fine crystalline dolomite containing calcite, in which cracks or fissures are mainly or locally developed. The main reservoir space types are also studied. Intergranular or intragranular dissolved pores constitute the main pore types in the study area, with intergranular holes and intergranular dissolved pores playing a secondary role.