EXTENSIONAL ACTIVITIES ALONG THE TAN-LU FAULT ZONE AND ITS GEODYNAMIC SETTING
Zhu Guang Wang Daoxuan Liu Guosheng Song Chuanzhong\ Xu Jiawei\ Niu Manlan (Department of Resource and Environment Sciences, Hefei University of Technology, Hefei \ 230009)
The extensional activities along the Tan Lu fault zone occurred in Late Cretaceous to Paleogene, resulting in development of a series of extensional basins along the fault zone. The fault bounded depressions along the fault zone occurred in the Anhui segment during Late Cretaceous to Paleogene, in the segment bordering Shandong and Jiangsu only in Late Cretaceous, and to the north of Weifang,Shandong in Paleogene,which indicates the depressions becoming younger from the south to the north. The extensional activities superimposed on the pre existing strike slip fault zone and showed episodic normal faulting. It is suggested that the extensional activities on the fault zone experienced five events of fault bounded depression. Extensional structures of the fault zone mostly show differences from a typical rift valley. They have the same geodynamic setting as a lot of other contemporaneous basins in East China. They were all developed under lithosphere arching in East China due to high angle, westward, perpendicular subduction of the Pacific Plate.