Dongpu depression is one of the few basins in China that are abundant with both oil and gas.Two sets of Paleozoic and Cenozoic source rocks

with deep burial depth and high thermal maturity

have gone through complicate history of bury

thermal evolution

and hydrocarbon generation.Good cap rocks represented by halite are well developed.Various types of sandbodies provide the depression with favorable accumulation conditions.Traps in the depression are of various types and the timing of their formation and hydrocarbon generation is ideal.Furthermore

the structural framework(two sags

one uplift

and one slope)of the depression and the abnormal high pressure in some part of the depression make it a favorable place for the migration and accumulation of hydrocarbon.Three types of gas reservoirs

including coal-derived gas

condensate gas and mixed gas

are recognized in the depression.The coal-derived gas reservoirs mainly occur in the top of central uplifts

condensate gas reservoirs mainly occur around the sags

and the mixed gas reservoirs are distributed in between.