Dongpu depression is a typical rifted basin in eastern China. The tectonic evolution of the basin includes an Early Paleozoic-Triassic cratonic basin cycle and a Cenozoic rift basin cycle. The latter can be subdivided into 4 stages

including initial rifting

intense rifting

late rifting and Late Tertiary integral downwar-ping. The basement extension in Dongpu depression increases

as a whole

from north to south. The extensional tectonic deformation is of simple shear extensional pattern in the upper earth crust

and of pure shear extensional pattern in the lower earth crust. The mutation zone of detachment surface might be the main factor causing the lateral tectonic transformation belt from Sangcunji to Qiaokou to Baimiao

and the difference of tectonic activity and the enrichment of oil and gas in the northern and southern parts of Dongpu depression.