The observed uneconomic production performance in many shale gas horizontal wells suggests refracturing as a restimulation treatment to revive economic gas production. To achieve high-performance re-stimulation, it is critical to select the right well among many other wells in the area and determine the proper time of refracturing. Well selection is challenging in shale gas horizontal wells because of the complexity of natural and induced fracture networks and in many cases due to insufficient reservoir and completion data. Selection of the candidate well and the time of refracturing can be made based on a thorough numerical simulation study developed by precise modeling of hydraulic fractures and refracturing process. Accurate modeling can only be accomplished by considering formation of fracture networks. Induced fracture networks are formed by an altered stress-field as a consequence of the fracturing process and are evidenced by micro-seismic hydraulic fracture monitoring techniques. Tavassoli et al. (2013) modeled gas production of a refractured well in the Barnett formation and validated their simulation methodology with the available field data. The validated model was used to predict gas production after refracturing the well. They then performed systematic sensitivity analyses to specify the characteristics of shale gas horizontal well suitable for refracturing and defined well screening criteria and optimal time of refracturing. In this study we extended their original work to study 188 horizontal wells in Barnett (Johnson County) to identify wells with potentials for refracturing. We found that among these 188 wells only 11 wells are suitable for refracturing and the best time to perform hydraulic fracturing is between 3½ to 5½ years after initial production.

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