ABSTRACT
The Rectangular Hyperbolic Method (RHM) is a steady state, finite system concept which has proved to be amazingly accurate in determining final static reservoir pressure at time of shutin. The method also calculates slope, skin, percentage of open reservoir thickness contributing to flow, effective drainage radius and permeability. It apparently also gives reasonable answers in horizontal well buildups. It has been found that all wellbore reservoir pressure buildups after all wellbore and storage effects have died out follow a rectangular hyperbolic curve. The analysis is based solely upon Darcy's steady state radial flow equation, the basic transient pressure buildup equation and the determination of effective drainage radius from Mt/Uo in an empirical equation based upon field date obtained from the literature. RHM is not related to any method based upon an infinite system concept.
