Tailored fluids improve shale drilling efficiency

摘要

Water-based fluid with a proprietary shale stabilizing agent cut average per-well drilling fluid cost in half. Wellbore stability issues had plagued early attempts by Southwestern Energy Company subsidiary SEECO Inc. to drill and complete horizontal wells in the Fayetteville Shale in Arkansas' Arkoma Basin. Unstable zones, particularly the Morrow Shale, had created operational problems including repeated instances of stuck casing and liners that had cost the operator significant time and money. Stabilizing these shale sections was critical to controlling drilling time and cost. Development activity to date has been primarily focused in Cleburne, Conway, Faulkner, Van Buren and White counties due to shale thickness. Of these, the westernmost counties of Conway, Faulkner and Van Buren typically are drilled with water-based fluids. Farther east, in White and Cleburne, oil-based systems are common.