More than 60% of US land wells drilled in 2017 are infill wells. Fracturing in such wells is likely to cause fracture hits on adjacent wells, which may have a negative impact on the infill and nearby existing well production. A new technology has been developed to control the geometry of the fracture, which reduces significantly the fracture hit rate and increases production in the child (infill) and parent wells.
Traditional methods for controlling the geometry of hydraulic fractures include adjusting pad and proppant volumes and fluid viscosity. The proposed technology uses an alternative approach, delivering a multimodal particulate diversion mix with the proppant. The job is designed so that the diversion mix bridges and accumulates at the fracture tip, thus confining the fracture perimeter and controlling fracture length growth.
The proposed technology has been field tested in 11 wells (219 stages) in the Eagle Ford shale. The results showed high efficiency of fracture hit prevention (84% of stages free of fracture hits) and increased production in the child and parent wells. The technology showed high operational reliability, (no premature screenouts) and was proven to be cost effective and robust. Laboratory experiments were conducted to tailor the permeability of the diversion blend. Because the diversion blend contains very small particulates, a wellsite delivery method was developed to prepare the blend and deliver it safely. Guidelines for the diverting pill pumping schedule were developed to optimize fracture hit prevention.
The developed technology demonstrates that the complicated process of fracture growth geometry correction can be performed with intelligent engineering design including a far-field diversion pill.