Pressure Transient Behavior of Vertically Fractured Wells in a Closed Square Multilayered Reservoir

Abstract

ABSTRACT This study presents the application of a new analytical model for analyzing pressure transient data for wells intercepted by a finite-conductivity vertical fracture in a closed square multilayered reservoir using the concept of a dual-porosity system. The solution takes into account the effect of wellbore storage. Our specific objectives are twofolded: first, to estimate fracture half-length, fracture conductivity and to correlate multilayered (two-layered) solution with the single-layer solution; secondly, to verify the numerical solution with the analytical solution. A set of asymptotic analytical (early-, intermediate-and late-time) solutions is also presented. In addition, we developed constant rate drawdown type curves applicable for analyzing transient pressure data. These type curves are used to match drawdown and buildup curves to determine fracture half-length, reservoir permeability and fracture conductivity. The results obtained from our type curves indicate that if the reservoir conductivity is known or can be calculated from given data, the estimated values of the aforementioned parameters compared favorably with the value? of the designed parameter. Although this study presents the solution to a twolayered system, it can be extended to a n-layered reservoir system.