Evaluation of heterogeneity impact on hydraulic fracturing performance

Abstract Hydraulic fracturing operation in tight reservoirs increases the connectivity of the well to more reservoir layers and further regions, thus boosting the production. Heterogeneity influences the hydraulic fracturing performance; this is observed when comparing the performance of different fracced wells. Those that far outperform other fracced wells are generally connected to more permeable rock or natural fractures. Modelling hydraulic fracturing net pressure provides hydraulic fracture dimensions and connectivity per fracture job. Moreover, well test interpretation can imply the active number of hydraulic fractures and an average estimation of their dimensions and connectivity after cleaning up and flowing the well. There is a technical gap in the integration of well test data with fraccing operational data for diagnosing and evaluating the hydraulic fracture performance. This paper introduces a novel approach to link the hydraulic fracturing modelling with well test interpretation. This method quantifies heterogeneity impact on hydraulic fracture performance through introducing a new parameter defined as Heterogeneity Impact Factor (HIF). The calculated HIF for the fracced wells varies between 74% (indicating that the well far outperformed the expected hydraulic fracture performance) to −65% (dramatically underperformed well). The outcome of the proposed technique was validated by geological observations and was subsequently applied to the dynamic simulation model. The pressure prediction of the model was compared with the three-week annual shut-down; the build-up response and its derivative display an excellent match which provides evidence for the robustness of the dynamic model and the effectiveness of the proposed technique.