Technology Focus: Hydraulic Fracturing (March 2009)

Abstract

Technology Focus "Besides black art, there is only automation and mechanization."—Federico Garcia Lorca, Spanish poet and playwright (1898–1936) On this basis, fracture stimulation sits firmly in the realm of mysticism, crystal balls, and tarot. The reason for this is that unlike automation (e.g., car manufacturing) we still are uncertain of what makes fracture stimulation "work" (i.e., the critical components) and of how we evaluate and improve performance (i.e., of what constitutes a "vehicle service"). The car industry understands the components that make a car operate because each is built meticulously and repetitively. The key components that drive fracture stimulation are more difficult to determine because the process is subject to a high degree of variability in subsurface conditions. And what adds more "smoke and mirrors" to stimulation design is that much of the research that forms our basic understanding was developed more than 30 years ago on tight gas reservoirs, which bear no resemblance to the shale, coal, or unconsolidated sands stimulated today. In other words, while we have paid for a Rolls Royce we unwittingly may be driving a DeLorean. The automotive industry assesses the performance of its cars through periodic, thorough checkups. How often do we conduct a multicomponent service on our stimulation treatments? Microseismics, continuous reservoir monitoring (by use of distributed-temperature surveys and permanent downhole gauges), and radioactive-fluid tracers are some of the technologies used to determine the "health" of stimulation treatments. Their use, however, remains the exception not the rule. Usually, expensive stimulation-treatment checkups are avoided; instead, only the oil dipstick continues to be used (i.e., pressure and rate during injection and production). Is it not time that you better understood the key components "under the hood" and gave a complete service to your fracture-stimulation process? Only through better understanding will the "black art" be replaced by science, the performance be measured, and step changes truly be made. Hydraulic Fracturing additional reading available at the SPE eLibrary: www.spe.org SPE 116124 • "Case History of Sequential and Simultaneous Fracturing of the Barnett Shale In Parker County" by P.N. Mutalik, Williams Companies, et al. SPE 118831 • "Optical-Fiber Distributed Temperature for Fracture-Stimulation Diagnostics and Well-Performance Evaluation" by Paul Huckabee, SPE, Shell E&P SPE 119350 • "Stress Amplification and Arch Dimensions in Proppant Beds Deposited by Waterfracs" by N.R. Warpinski, SPE, Pinnacle SPE 111431 • "New Viscoelastic Surfactant Fracturing Fluids Now Compatible With CO2 Drastically Improve Gas Production in Rockies" by K. Hughes, Chevron, et al.