A Computer-Oriented Method of Pressure Build-Up Analysis

A method of estimating reservoir pressure from pressure build-up information has been developed which utilizes a mathematical analysis of the measured pressures to determine that portion of the pressure build-up history to be employed in the bottom-hole pressure extrapolation. The reservoir pressure is then determined by a linear regression analysis of those data to be included. As only the shut-in time and the measured pressures are required, the results do not depend on correct estimates of additional reservoir factors. The method does, however, yield information on the basis of which estimates of reservoir transmissibility can be made. The method can best be employed utilizing a digital computer because of the large number of calculations required. The technique is particularly useful in the routine analysis of pressure build-up information, because the calculations can be carried out with a minimum of engineering time.