Regulators say the blowout that killed five workers on a Patterson-UTI rig in Oklahoma was the product of a slow-moving series of missed signals, misleading testing, and miscalculations that failed to control a natural gas influx. The new well control rule is evidence that memories of the Macondo blowout remain a powerful force for caution. Despite the rhetoric on both sides of this hot-button issue suggesting big changes, the final changes were incremental. Nonaqueous drilling fluids, such as synthetic-based and oil-based mud (SBM and OBM, respectively), are used frequently to drill one or more sections of a well to reduce drilling problems such as shale sloughing, wellbore stability, and stuck pipe. Three onshore fields in the Emirate of Sharjah, United Arab Emirates, have more than 30 years of production history from more than 50 gas-condensate wells.