CONDITIONS AND MECHANISM OF HYDROCARBON ACCUMULATION IN OVERPRESSURED SYSTEMS IN SEDIMENTARY BASINS

The research and practice of exploration show that overpressure systems in sedimentary basins have close relationship with hydrocarbon occurrence and are significant for exploration of deep reservoirs Overpressure inhibits or retards the generation and maturation of hydrocarbon and improves the porosity and permeability of the reservoirs It also strengthens the sealing for hydrocarbon and broadens the range ofliquid state windowwhich determines the accumulation and pooling of natural gas So it creates favorable conditions for the exploration and development of reservoirs in the deep of basin Overpressure systems formes independent hydrocarbon accumulation systems as a form of compartment from which fluid releases repetitively through a cycle of healed state to fracturing state There are still many problems to resolve, especially for the relationship between overpressure and hydrocarbon generation, which has been argued, and the mechanism of hydrocarbon accumulation in overpressure systems The issues of hydrocarbon accumulation in overpressure systems will be important tasks for oil or gas exploration in future