Simulation of source rock evolution in Carboniferous, eastern Junggar Basin

The histories of bury, thermal evolution and hydrocarbon generation of Carboniferous source rocks in the east of the Junggar Basin were studied by means of the TSM basin stimulation software. It was concluded that the depocenter of the study area transferred from the south to the north and then back to the south from Jurassic to Cenozoic. In the Jimsar Sag in the south of the basin, the source rocks in the Batamayineishan Formation gave birth to hydrocarbon during 2 key periods:1) the end of Jurassic when the R_o of source rocks ranged from 0.6% to 1.3%; 2) after the middle and late Cenozoic when the R_o of source rocks ranged from 1% to 2%. In the Wucaiwan Sag in the north of the basin, the source rocks in the Dishuiquan Formation generated hydrocarbon mainly at the end of Cretaceous when R_o ranged from 0.7% to 1.5%, indicating a large amount of hydrocarbon. In the Shiqiantan Sag in the north, the source rocks in the Shiqiantan Formation entered the threshold for hydrocarbon generation at the end of Cretaceous and the evolution degree was low. The hydrocarbon intensities of the Dishuiquan and Bashan Formations were higher, amounting to 200 mg/g, while the highest value of the Shiqiantan Formation was only 40 mg/g.