Pressure-Derivative Type Curves, for Vertically Fractured Wells

This paper presents a technique for interpreting pressure-derivative type curves for a vertically fractured well located in an infinite reservoir. These type curves can be used to match pressure test data to determine the formation permeability, the half-length of the fracture, and the nature of the fracture—i.e., uniform-flux fracture or infinite-conductivity fracture. At long producing times, the buildup type curves are identical to the drawdown type curves for both types of fractures.