During the evolution of Baiyinchagan depression

various types of transfer structural accommodation systems have been formed in different parts of the extensional structure

due to the elevation and subsidence of the basement and uneven faulting. Maohu swell in Baiyinchagan depression is a large transfer structural zone

which consists of two synthetic oblique accommodation zones and one strike-paralleled accommodation zone. The structural accommodation zones in the western sag can be divided into 4 types

including antithetic anticline accommodation zone

synthetic transverse accommodation zone

synthetic oblique accommodation zone and strike-paralleled accommodation zone. Exploration practices show that there are well developed structural

lithological and overlapping unconformity traps in the Xilinhaole

Darqinan

Darqidong and Wongte accommodation zones and their adjacent areas in southern part of the western sag

and they have long been in the major direction of hydrocarbon migration. Therefore

they are favorable for the accumulation and enrichment of hydrocarbons.