Horizontal well fracture interference - Semi-analytical modeling and rate prediction

A semi-analytical superposition model for analyzing pressure and rate data from wells where production characteristics were altered because of interference from nearby fracture operations is presented. In previous work (Thompson (2017)), specialized numerical simulations showed that these production changes could be explained by changes to the total fracture half-length and fracture permeability; in turn, these parameters alter the completion's linear flow parameter, kA, (which we loosely refer to here as the well's linear “flow capacity”) and “skin” pseudopressure drop (i.e., steady-state unit rate pseudopressure drop between the matrix and the wellbore). Superposition equations that govern fracture interference events under the assumption of linear flow to the fracture system are presented. The model is semi-analytical since no account is taken of variable gas compressibility effects in the superposition equation. Application of the technique allows quantification of interference-induced changes to both flow capacity, (kA) and skin pressure drop. By inverting the model, a method of predicting the well's production performance post-interference, given the changes to flow capacity and skin and a bottom-hole pressure production schedule, is developed. The predicted rate schedule is valid as long as the well remains in linear flow. The validity of the model is illustrated by applying it both to synthetic and a field production data. Based on the synthetic data, it is demonstrated that the superposition model can accurately describe changes to flow capacity and skin, and that the obtained model parameters can be used to reproduce the model rates given imposed bottom hole pressures. The method is applied to a field example where an interference event occurred, and demonstrates very good agreement between model predicted rates and observed field data.