From the Late Jurassic to Cretaceous, due to the sinistral shearing of the Tanlu fault, the earlier reverse faults inversed negatively, and some semi-grabens developed.

• 早、中侏罗世是对晚三叠世挤压逆冲断层和褶皱所造成的本区地势高低起伏的一个截凸填凹、填平补齐的过程;