Migration characteristics of oil and gas is summarized as below: 1)Hydrocarbon discharge ratio of 2 sets of mature source rocks (K_1ba and K_1bt~1) in the Lower Cretaceous is about 32%-72%, thus estimated as the main hydrocarbon discharge stratum.

• 主要的认识为:1)本区下白垩统K1ba和K1bt12套成熟烃源岩排烃率可以达到32%25~72%25,是主力排烃层。