Discoverer Spirit Sets Ultra-Deepwater Drilling Record

Transocean Sedco Forex Inc. has set another world record for ultra-deepwater drilling when the company's Discoverer Spirit drillship spudded an appraisal well in 9,727 feet of water in the Gulf of Mexico for Unocal Corporation.

The Discoverer Spirit installed and tested blowout prevention equipment October 27 and 28 on Unocal's Trident 2 well in Alaminos Canyon block 903, surpassing the previous industry water depth record, also held by the Discoverer Spirit, for drilling in 9,687 feet of water. The prior record was set in May 2001 on the first Trident well in Alaminos Canyon block 903.

The Discoverer Spirit utilizes Transocean Sedco Forex's proprietary dual-activity drilling process. Along with Unocal's unique approach to low-cost drilling, dual activity is designed to reduce by approximately 15% the time required to drill exploration wells and up to 40% for production wells. Dual-activity time savings are achieved by performing drilling tasks in parallel steps instead of sequentially with conventional offshore drilling rigs. To date, the Discoverer Spirit has drilled five deepwater exploration wells in the Gulf of Mexico for Unocal, resulting in significant time savings.