Abstract: South Yellow Sea Basin is one of the major petroliferous basins offshore China.It has been explored for years but with no significant commercial discovery due to a lack of understanding of its structure,diversified fault systems and complicated tectonic evolution.To evaluate the exploration potential and gain insight into faulting activities and sedimentation of the basin,we performed characterization of the tectonic deformation and formation mechanism analyses of the northern sub-basin in South Yellow Sea Basin since the Late Cretaceous based on a combination of the latest two-dimension seismic data with relevant geologic setting,drilling data and previous research papers.It shows that thrust faults were formed in the marine strata due to the compression and deformation the Indo-China period,and the fault system served as the basement faulting system since the Late Jurassic.It was later reactivated by extension and controlled the activities of faults within the basin as well as the sedimentary framework.A faulted depression cluster that was dominated by extensional structural deformation formed,reflecting a relationship of shallower strata being constrained by the deeper ones.

Key words: tectonic deformation, basement fault, fault depression, basin genesis, South Yellow Sea