Estimation of horizontal reservoir anisotropy without type-curve matching

Normally, interference testing involving at least three observation wells is used for estimation of areal anisotropy in hydrocarbon reservoirs. Current interpretation techniques are mainly based upon by pressure type-curve matching which is basically a trial-and-error procedure. This paper has been written with the purpose of overcoming this issue. Therefore, type-curve matching procedure is replaced by a pressure and pressure derivative interpretation method which follows the TDS technique philosophy, so that directional permeability can be easily estimated. The provided methodology allows to practically and accurately estimate anisotropy and carry out a quantitative estimation of both the maximum and minimum directional permeability values, and the angle formed between the x axis and the maximum permeability semi-axis. Additionally, the average permeability value is re-estimated. A field example proposed in the literature and a synthetic example have been successfully solved for verification purposes.