In these profiles, the depth-coordinate is with respect to sea bottom, and thus to obtain the actual depth to an interface, the respective bathymetry or paleobathymetry must be added. Critical parameters in this analysis are the sediment specific storage, hydraulic conductivity and hydraulic diffusivity. Many of these parameters have equivalents in the equations describing the conductive-advective flow of heat. Specific storage is the property of sediment to retain fluids during pore pressure variations. It is formally defined as the amount of fluid expelled due to a unit increase of hydraulic head.
Hydraulic conductivity defines the rate at which a fluid can pass through a porous medium.
The hydraulic conductivity is directly proportional to the sediment permeability which can feasibly decrease 3 orders of magnitude within the upper sections of a sedimentary basin. Hydraulic diffusivity is defined as the ratio of hydraulic conductivity and specific storage. The generation of overpressure is caused mainly by the rapid deposition of sediment. The inability for pore pressure to escape at a rate commensurate with sedimentation leads to sediment overpressuring. The selected well represents a typical geological situation in the Gulf Coast region where massive progradational sands overlie sands and intercalated shales which in turn overlie massive shales.