Investigation of Improved Conductivity and Proppant Applications in the Bakken Formation

Abstract

Abstract Production from the Bakken and Three Forks Formations ("Bakken petroleum system") within the Williston Basin is continuing to climb as a result of applied horizontal drilling and hydraulic fracturing. Key to increased oil production is the evolution of reservoir stimulation techniques, such as fracturing fluid systems and proppant types. This study evaluated the key factors that may result in conductivity loss within the Bakken and Three Forks reservoirs. Various proppants and reservoir rock cores were exposed to common fracturing and formation fluids at reservoir conditions. The hardness of the rock cores and the strength of the proppants were evaluated prior to and following fluid exposure. The conductivity of various proppants, as well as formation embedment and spalling, was evaluated at reservoir temperatures and pressures using actual reservoir rock cores. The results of this work suggest that certain fluids may affect both rock and proppant strength and, therefore, garner consideration. The conductivity of propped fractures within the Bakken petroleum system appears to be a function of a variety of factors, including proppant and rock strength, as well as formation embedment and spalling. The results of the study highlight that advanced conductivity testing, coupled with quantification of formation embedment and spalling, can provide further understanding. Given the importance of fracturing fluids and proppant performance on conductivity and ultimately, oil recovery, a better understanding of the effects of these various factors on proppant and rock strength in the field is vital for more efficient production within unconventional oil and gas reservoirs.