Optimization of High-Pressure, High-Rate (HP/HR) Gas Wells in a Giant Offshore Field

Abstract

Abstract An extensive large bore gas well drilling program is ongoing for the development of Qatar's North Field. This massive offshore carbonate field contains abnormally-pressured natural gas produced from the Khuff reservoir at ~10,000-ft TVD. In the most extensive application of large bore wells in a single field development, this program involves a large number of wells drilled under challenging subsurface conditions. These large bore wells maximize the gas contribution of each well and reduce overall field development costs by minimizing the number of wells and facilities required. Significant design and operational enhancements made during the program have dramatically reduced drilling time and cost without compromising safety or integrity. In addition to reducing drilling time by over 40%, specialized procedures have been developed for managing major challenges including complex lost returns and well control events.