This paper summarizes the types of the Cenozoic folding

their controlling factors and distribution in the Bohai Sea waters based on seismic data interpretations.According to their mechanical genesis

the folding can be classified into four types which are respectively related to extension

wrench

compression induced by gravity sliding

and compaction and diapirism caused by gravity.Extension-related folding and compression-rela-ted folding happened during the Paleogene and these two types of folds are distributed along the long-active main faults and slopes respectively.Wrench-related folding happened during the Neogene and the folds are distributed in the eastern part of the Bohai Bay Basin where the Tanlu fault zone passes by.Among the gravity-related fol-ding types

the drape folding had been active in the whole Cenozoic and the folds are distributed on the salient.While the salt diapirism folding was restricted to certain areas and the faults occur only in the Laizhou Bay sag at the south of the basin.The current exploration results in the Bohai Sea waters show that traps located along the faults and related to the wrench folds of the Late Neogene are favorable for oil and gas accumulation.