Paleokarstification and reservoir characteristics of the lower ordovician dolomite in the north of tarim basin, Xingjiang

摘要

Lower Ordovician dolomite undergoes polyphase and polycyclic paleokarstification during Early Hercynian, Late Hercynian-Indo Chinese epoch, so that an excellent karst type reservoir develops. Paleokarst landform can be divided into karst uplift, karst clinoform and karst basin area, and secondary Highland on the uplift and clinoform area is the most favorable to the formation of corroded pores, holes And fissures of reservoir. Corrosion of reburial stage further improves the quality of reservoir, but filling Reduces the porosity and permeability of reservoir.