Konstantin Sinkov, Dimitry Chuprakov, Maxim Chertov, Dean Willberg, Pavel Spesivtsev

The phenomenon of cascading fracture failure during flowback and initial production from a horizontal multistage hydraulically fractured well is introduced, described, and investigated. First, a simplified analytical model of production from such well is built. This model allows evaluating a range of systems parameters through which the cascading failure evolves and performing a sensitivity study of this effect. Next, while keeping the physical model of the system relatively simple, the critical flow rates causing the motion of proppant pack in fractures are treated as random variables. This assumption brings the next level of sophistication to the model and allows demonstrating non-obvious effects. In particular, the well production rate losses due to cascading fracture failure are estimated. Finally, the proposed hypothesis is validated by conducting numerical simulations of flowback in the estimated conditions of cascading failure. As a practical outcome of this study, recommendations on the mitigation of the well productivity failure caused by cascading failure are formulated and discussed.