Abstract:

The origin of North China Basin is due to the disintegration of North China fault block. Based on the structural, geophysical and petrogeochemical data,the disintegration is related to followinh factors: 1.It is related to the uplifting of the mantle resulted from lithosphere fractures, suck as Taihang, Cangxian and Tanlu fractures. When the fractures penetrated the lithosphere and reached the mantle.they would cause local reduction of pressure to promote partial uplifting of the mantle and crustal extension. Then the extension shifted to the center from edges of the basin with the transformation of the mantle rising anomaly. 2.It is possible that buried ridge formed about 100 million years age ledto crustal extension in N-S direction and E-W trending fractures, such as Beitang-Leting fracture and Qihe-Guangrao fracture. They accelerated the extension process of the basin. 3.Polylayer texture of crust constituted a condition for the disintegration of the fault block and the development of rift valley. The basin contains a series of uplifts and depressions, thus forming various assemblages of source beds and reservoirs. In consideration of its sedimentation.deformation and evolution. the Bozhopg Depression and its adjacent areasare most favourable for the accumulation of oil and gas.