Hydrocarbon accumulation characteristics of volcanic rock reservoir in middle segment of Eastern sag of Liaohe oilfield

Based on systemic analysis of essential factors of hydrocarbon accumulation such as source rock, reservoir, cap rock, hydrocarbon migration, trap and reservoir-seal relationship in Eastern sag, the accumulation models of volcanic rock reservoir of this area was established. It shows that volcanic rock has the characteristics of being formed early, adjacent to source rock, short time of volcanic activity and strong faulting activities, which are special conditions for hydrocarbon accumulation of volcanic rock reservoir. Two main hydrocarbon accumulation models of volcanic rock reservoir in the study area are structural-lithologic reservoir model and lithologic reservoir model. The former is located in the anticlinal zone of median fault belt and dominantly characterized by vertical migration, the later is in the east of Jiazhangsi Fault and dominantly characterized by lateral migration.