The formation pressure in the Dongpu Depression falls into three zonesin vertical direction: the normal hydrostatic pressure zone

the transitionalpressure zone and overpressure zone. The area of highest excess pressure issituated in the east sag zone. Formation water flows generally from medium-deep level of the centers of the sags to the marginal zones of the depres-sion

thus forming a typical centrifugal percolation system. The zones andareas of hydrodynamic environment in this region are discussed.