REVIEW ON FORMATION MECHANISM OF THE RESERVOIR OVERPRESSURE FLUID SYSTEM

A reservoir overpressure fluid system (ROPFS) is an assembly that constitutes overpressured fluid, its related essential geological elements and their interaction, confined by pressure seal. The essential elements include pressure seal, overpressure fluid, rock matrix, and conduits. Environmental fluid system of a pressure fluid system is the sum of external geological elements and their interaction. The degree of overpressure in reservoirs may be higher or lower than that in their surroundings, or the same, because they are in different environments. Mechanisms capable of generating reservoir overpressure fluid system include overpressure transference, nonequilibrium compaction, fracturing gas generation and buoyancy. Most of reservoir overpressure fluid system results from accumulation of hydrocarbons. Overpressure relief is an essential factor for hydrocarbon accumulation in overpressure fluid system. The study on the reservoir overpressure fluid system can help us to understand directly the migration and accumulation of hydrocarbon in overpressured petroleum basins.