Journal of Natural Gas Science and Engineering   2016 年 34 卷

2016.08.01

Hydrous pyrolysis experiments were conducted on immature petroleum source rocks to define the roles of pressure and hydrocarbon expulsion in deep petroleum formation. This study can contribute to estimating the deep oil and natural gas prospects of lacustrine type-I kerogen and has important implications for deep petroleum exploration. The simulation temperature was 450 ?°C and the heating duration was 48 h. Water pressure ranged between 50 and 1200 bar, and lithostatic pressure ranged between 125 and 2000 bar. Under semi-closed conditions, increasing water pressure leads to more oil and less gaseous hydrocarbons being generated in the source rocks. The dryness of the hydrocarbon gas primarily confirms that increasing water pressure decreases the cracking magnitude of oil, which may indicate that high water pressures retard oil cracking. The decreasing contents of S