| This dissertation presents an efficient and effective economic optimization scheme for hydraulic fractures in high permeability formations. The optimization scheme incorporates global optimization algorithms that simultaneously optimize all of the treatment parameters while accounting for the required constraints. A user-friendly computer program was developed and used to demonstrate the utility of the optimization scheme. Parametric studies were conducted, and some general trends and guidelines were observed. Field data from frac & pack treatments were reviewed and compared to the findings of this research. The main contributions of this work are presented below. (1) A formal approach to optimizing frac & pack treatments has been introduced. The optimization scheme can be used to determine if a frac & pack treatment is an economically attractive option for a given reservoir, and if so, what are the optimal fracture dimensions and operational procedures? The optimization algorithms are more efficient than the approaches that are currently used, our approach simultaneously optimizes all of the treatment variables while ensuring that operational and economic constraints are satisfied. This is more efficient than the current approaches for fracture design optimization. The scheme is not dependent on specific fracture geometry or production prediction models. (2) Parametric studies demonstrated the utility of the optimization scheme and allowed the identification of some general trends and guidelines for designing frac & pack treatments. Issues such as the scope of applicability of high permeability fractures and fracture dimension trends were investigated. While limited in their scope, these studies represent a starting point in the quest for a better understanding of frac & pack behavior. (3) A review of field data indicates that the results of our optimization scheme are realistic, confirming some of the conclusions derived from the parametric studies and suggesting that this approach can be a useful tool for designing fracture treatments in high permeability reservoirs. |
