Burial history and thermal evolution characteristics of source rocks of the Upper Triassic Xujiahe Formation, Sichuan Basin

According to the geologial data and the present geothermal and paleogeothermal data from 52 exploration wells, the authors analyzed the changes of burial history，maturity evolution and thermal history, and gas generation with time of each well with PetroMod software. The results show that the Upper Triassic source rocks in northern and middle Sichuan basin came into the oil-generating window in middle and late Jurassic, respectively. However, the Upper Triassic source rocks in southern Sichuan basin entered into hydrocarbon generation threshold in Early Cretaceous. The source rocks continued to be buried at the greatest depth and then reached the oil-generating peak until the late stage of late Cretaceous. After that, Sichuan basin experienced a uplifting process as a whole under the late Yanshanian and Himalayan movements, while the thermal evolution of kerogen was ended eventually.