Abstract:
The Ordos basin located in the west part of the North China craton is one of the large petroleum-bearing basins. It has a complex and obviously heterogeneous basement structure with two large uplifts on top of the basement. The northern one is called the Yimeng paleouplift, and the south-central one, the Central paleouplift. The Yimeng paleouplift inherits the shape of the crystalline basement, with the Upper Carboniferous directly covering the metamorphosed basement; whereas the Central paleouplift is the Paleoproterozoic passive continental margin that originated from the western and southern margins of the Ordos basin on the basis of the Proterozoic Qinling-Qilian-Helan triple rifts and developed as an active continental margin. During the Middle Ordovician to Middle Carboniferous, the Qinling-Qilian ocean trough was subducted and collided in east and north directions, thus forming the Paleozoic foreland basin, and its front bulge formed the L-shaped Central paleouplift.