A significant quantity of hydrocarboneous fluid is produced at a critical depth in sedimentaly basin by the dehydration of caly minerals under the diagenetic conditions of overburden pressure and heat. The dissociated liquid accompanied with the formation water primarily causes an abnormally high pressure zone at the stratum. If any exceptional force does not occasionally act on for basin, the fluid may be stationally pressed out into a porous medium and driven to final reservoir for a considerably long period of several million years. The driving force of migration is however not only the hydro- and lithostatic pressure, but also a tectonic stress. Regarding to a younger oil basin in the tertiary orogenetic system, the emulsive hydrocarbons are not ready to be held in the primary formations, but run off to more stable and porous reservoirs through a large number of cracks and fractures developed temporarily within the basin by means of destructive stresses of earthquakes or volcanism. Numerous seismic and volcanic activities which magnitudes are generally small and occasionally leage, are relevantly connected to the oil tertiary evolution in this country. The diffusive periods and ranges are estimated to be comparable to the order of the build-up times and the dimensions of the events. The migration of hydrocarbon is thus so frequently synchronized to the dynamic activities of the basin that accomplished more rapidly on a farther scale than estimated with static permeation of the fluid.
