M.Y. Soliman and Dean Prather, Halliburton
Fracturing has become a viable and important option for completing horizontal wells. This is especially true in case of tight gas formations. There are many fracturing processes and methods to consider for placement of these fractures. The optimization of the completion process including the number and size of fractures is still a challenging consideration. Fracturing of a horizontal well has unique aspects that require very special attention to obtain successful treatment. Differences between horizontal and vertical wells exist in areas of rock mechanics, reservoir engineering, and operational aspects. All of these aspects affect the optimization process for successful treatment placement and optimum asset performance. In this paper we will first discuss the various factors crucial to successful completion of a fractured horizontal well. We will discuss these factors in relation to both longitudinal and transverse fracture applications. Success factors will include the optimum perforation process, overcoming fluid flow convergence towards the wellbore in case of a transverse fracture, and the fluid flow and stress interference between multiple fractures. The paper will present field cases, laboratory, and numerical experimentations illustrating the impact of the various factors on the completion of the horizontal wells and the optimization of the fracturing process. The paper will also point to unique aspects that may be encountered during fracturing a horizontal well in tight gas formations.