Analyzing the discovered carbonate reservoirs in the Tazhong area, Tarim Basin indicates that the development of a reservoir is controlled by subarial weathering and freshwater leaching processes, sedimentation, early diagenesis, and alteration by deep fluids. According to the origin and lateral distribution of reservoirs, the hydrocarbon accumulation zones in the Tazhong area are classified into four types: buried hill and palaeoweathering crust, organic buildup reef-bank, dolomite interior, and deep fluid alteration. Different types of carbonate hydrocarbon accumulation zones are distributed mainly in specific areas of the Tazhong uplift. Because of the different mechanisms of forming reservoirs in different carbonate hydrocarbon accumulation zones, the reservoir space, reservoir capability, type of reservoir and distribution of reservoirs are often different.
Characteristics and Accumulation Mechanism of Quasi-Layered Ordovician Carbonate Reservoirs in the Tazhong Area, Tarim Basin