HYDROCARBON ACCUMULATION MODEL FOR OVERPRESSURE BASIN: AN EXAMPLE FROM THE YINGGEHAI BASIN

Overpressure sedimentary basins are widely distributed and of great significance to hydrocarbon exploration. This kind of basins has many advantages for hydrocarbon accumulation: The overpressure formation is not only a beneficial source rock, but also an effective capping layer. Abnormal high pressure fluid flowing through reservoirs may meliorate the reservoir properties and control the formation and distribution of traps. Overpressure fluid flow may improve the oil and gas migration system, and provide a driving force for oil and gas migration. Based on the study of overpressure basins, we put forward in the paper a funnel-shaped meshwork-carpet type hydrocarbon accumulation model. The overpressure diapir is the core for hydrocarbon accumulation in overpressure basins. Driven by high pressure, oil and gas will migrate along the funnel-shaped passage system into the overlying low-potential zone above the diapir.