A common limitation of fracture stimulation is the inability to control placement of a hydraulic fracture. This shortcoming compromises the effectiveness of a fracture treatment for multistage treatments during early field development, as well as single stage fracture stimulation of bypassed zones in mature reservoirs. This limitation can be overcome by integrating coiled tubing with hydraulic fracturing. This combination adds versatility to the fracturing procedure. It also permits control of fracture placement and hence can be used to improve the economic benefits associated with hydraulic fracturing.
The effectiveness of coiled tubing fracturing operations can be constrained by excessive friction pressures, equipment limitations and limited fluid and proppant volumes. Its application thus requires specialized fracture fluids, additional field operational considerations, and alternative design procedures to ensure an efficient and successful fracture stimulation program.
The paper initially explains the motivation for coiled tubing fracture treatments. Operational and design requirements associated with this technique are then outlined. Two case studies are finally presented to illustrate the application of the coiled tubing fracturing procedure.