Unsteady Crossflow Model for Leaky Vertical Interference Testing Across a Low-Permeability Zone

A new unsteady crossflow model is developed in this chapter for the leaky vertical interference well tests in a three-layered reservoir with the middle layer being a low permeability one. This kind of test considers the leakage rate between the active and observation layers behind the casing or through a leaky packer. This new model considers the vertical permeabilities and storativities of all three layers and includes the pseudosteady crossflow model and unsteady crossflow model, previously used, as its special cases. Different models are compared using simulation results.