Basin modeling and its application in the south part of Songliao Basin

The basin modeling in the south part of Songliao Basin mainly consists of simulations of structural evolution history, burial history, hydrocarbon generating and hydrocarbon expelling history, and hydrocarbon migration and accumulation history. Investigations on the amount of hydrocarbon resources and the resource structure were performed in the fault depressions of Shiwu, Dehui, Fulongquan, and Liutiao in the area. The main hydrocarbon source rock in the south part of Songliao Basin is Shahe Formation, the secondary hydrocarbon source rocks are formations of Huoshiling and Yingcheng. The Dehui Fault Depression possesses the highest hydrocarbon generating amount (628×10 8 t) in the four fault depressions, and the Shiwu Fault Depression the second (239.08×10 8 t). The highest evolution degree of hydrocarbon source rock is in Shiwu Fault Depression with oil to gas of 1∶17, the Liutiao Fault Depression the lowest with oil to gas of 1.2∶1. It can be seen from the modeling that the intensity of hydrocarbon generation is greater than 40×10 4 t/km 2 , and the intensity of hydrocarbon expulsion is more than 20×10 4 t/km 2 in areas with commercial hydrocarbon accumulations. The area exhibits clear directional migration convergence and relatively strong migration intensity.