| Most of the salt-bearing basins are also oil and gas bearing areas. In the exploration of oil and gas in salt-bearing basins, it has been found that there are some close relationships between salt and oil & gas. With regard to the causes of formation and sources of salt, people have different point of views in different basins, and different depositional models are set up, even in one same basin there are also divergent view to exist Different opinions still exist on the position of the salt bearing strata in sequence stratigraphy. It will greatly influence the exploration level of resources in salt-bearing basin if the above doublts can not be made clear. In this way, it will be of great significance to make it clear about the above issues and the relationships about salt and oil & gas. Several thick beds of salt rocks are developed in Shahejie Formation, Eocene in Puwei sag, Dongpu depression of oil and gas bearing Bohaiwan basin, and huge amount of oil and gas are accumulated there. It will be both practical value and theoretical significance to systematically research the causes of formation, sources of salt, and development regulations of the thick beds of salt rocks in Puwei sag, and to probe into the relationship about salt and oil and gas accumulations, under the direction of sequence stratigraphy and sedimentology theorys and metheds, conbined with the analyses of the colligation of structures and strata, geophysics, geochemistry, basin analysis, and oil and gas bearing systems theorys and methods, on the basis of the synthesis analyses and dissections of cores, logs and seismic data.With an area of 5300 km2, Dongpu depression is located in the southwest of Lin-qing depression, Bohaiwan basin, bounded with Lu-xi uplift by Lan-liao fault in the east, with Nei-huang uplift by Chang-yuan fault in the west, with Lan-kao heave by the north Feng-qiu fault in the south, with Xin country depression by Ma-ling fault in the north, while spreading along NNE defection, taking on the forms of being wide in the south, and narrow in the north. It is a rift fault depression basin with the characteristics of striking, with the basement being the Paleozoic and Mesozoic, and the capping beds being the Cenozoic. Tectonically controlled by the NNE and NW direction faults, it is divided into 5 subunit by the intercept of the NNE and NW direction faults, from west to east i. e. the west slope belt, the west sag belt, the central upheave, the east sag, the east Lan-liao fault steep stair belt Dongpu depression takes on the characteristics of being subarea northsouth, and being belt disparted westeast in the evolution of tectonics and forms of sedimentary facies.Tectonically located in the north of the central upheave of Dongpu depression, being one of the major oil-generating sag in Sha-3 member, Puwei sag is a subunit sag of Dongpu depression, which is clamped between Pucheng-chenyin and Wei-dong fault. With the basement dipping east, and being complicated by several reverse fault, Puwei sag is a dustpan-like sag. Based on the characteristics of faults which controlled the sag and other structures, Puwei sag can be divided into 3 hypo-subunit i. e. the west reverse fault ridge belt, the central sag belt the east orderly fault steep stair belt.Structure analysis indicates mat the tectonic evolution of Puwei sag is controlled by Pucheng-chenyin and Wei-dong fault. The seismic coherence cube makes it clear that the two faults are composed of a series of paralleling or approximately paralleling or wold goose line pattern fractures, with the deep and the shallow part of the two faults being much different.On the basis of the characteristics of sequence stratigraphy of the Cenozoic in Puwei sag, Dongpu depression, the sequence stratigraphic framework of the Cenozoic is set up, including two supersequence sets which is fault depression filling supersequence sets of the Eocene, and depression filling supersequence sets of the Tertiary. The fault depression filling supersequence sets of the Eocene can be divided into 3 supersequ...
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