Hydrocarbon accumulation and distribution in lower Paleozoic carbonates in Tarim Basin

Carbonates are the main exploratory layers in Tarim Paleozoic cratonic basin. With abundant oil and gas sources, the lower Paleozoic carbonate in which traps develop over a large area and at a high amplitude, has the basic condition to form large oil and (or) gas fields. Three types of petroleum accumulation models, which consist of buried-hill petroleum accumulation in the high part of the uplift, inner structure petroleum accumulation in the pitching part of the uplift and fault horst petroleum accumulation on the border of the uplift, are found in the lower Paleozoic carbonates. Petroleum occurrence is mainly controlled by paleo-uplift, fault, unconformity and fracture system. The pitching part of the paleo-uplift and the fault belts on the paleo-uplift are the favorable exploratory areas.