Dongpu depression, a oil-gas bearing basin, is situated in the southwest Bohaiwan basin.Puwei sag is a subunit that is tectonically located in the north central upheave of Dongpu depression.

东凹是渤海湾西南部的一个含油气，造位置上处于东凹中央隆起带北部，为一负向次级造单元。