Hydrocarbon-generating dynamic characteristics of paleogene source rocks in western depression, Liaohe basin

The experiments of hydrocarbon-generating dynamics in opening system on 18 samples of different lithology and kerogen types in western depression of Liaohe basin were carried out, and the results show that there exists huge difference between different kerogen types of the same lithology: the better the kerogen types, the lower of the average activity energy; while the larger of the corresponding reaction fraction of dominated frequency activity energy, the narrower distribution range of the activity energy, which shows that the kerogen type has a deciding function on hydrocarbon-generating of the source rock. By using the parallel first-order reaction model, taking the burial history and thermal history into comprehensive consideration, we did a quantitive study on the hydrocarbon-generating history of the source rock of the western depression, Liaohe basin. The results show that the Sha 3 and Sha 4 formations are the main source layers, which account for 63.9% and 18.5% the total amount of hydrocarbon-generating respectively. Sha 1-2 and Dongying formations are the secondary source rock layers, and the accumulative hydrocarbon generation amounts to 328.09108 t of the four source rock layers in total. The Dongying deposition period is the main hydrocarbon-generating time.