Technological advances in oil and natural gas development and the increasing availability of existing infrastructure are reducing the interval from the discovery of commercially recoverable hydrocarbons to production, while at the same time allowing new discoveries that are smaller in size to be economically viable. This is especially true in the deepwater U.S. Gulf of Mexico (GOM), one of the Nation's major producing areas.
In June 2011, Eni began producing oil at its Appaloosa field in the deepwater GOM, just a little over three years after it was discovered in the Mississippi Canyon area in water depths of about 2,500 feet. But for delays associated with the temporary deepwater drilling moratorium in the wake of the Macondo disaster, production might have commenced even earlier.
Noble Energy's Santiago field, with a depth of about 6,500 feet, was the first deepwater GOM discovery issued a permit following the temporary drilling moratorium, and is expected to be brought on stream in less than a year from that time. This very short discovery-to-production interval, particularly for an "ultra-deepwater" field (water depth of at least 5,000 feet), is possible in part because Santiago is part of a three-field joint development called Galapagos, which includes the Isabela and Santa Cruz fields now under development that were discovered in 2007 and 2009, respectively.
The timetables for Appaloosa and Santiago reflect a marked acceleration from typical experience during the 1980s, 1990s and 2000s, when the average interval from discovery to production for deepwater fields was 11.4 years, 5.9 years, and 3.3 years, respectively (Figure 1). The comparatively quick turnaround for many of the more recent GOM discoveries primarily reflects their proximity to existing production and transportation facilities put in place during development activity associated with earlier discoveries. Several 2000s-vintage discoveries at locations inaccessible to existing infrastructure have taken much longer to reach production - between 7 and 10 years.
Technological advancements in subsea development systems are also playing an important role. Fields that may have been considered too small, deep, or remote to develop using production platforms in the early phases of deepwater exploration are being "tied back" via subsea flow lines to existing platforms, significantly reducing both costs and the lag from discovery to initial production. Appaloosa, for example, is producing through a 20-mile flow line connected to the Corral fixed steel production platform situated in the shallow water GOM shelf. The Galapagos fields will be tied back to BP's Na Kika semi-submersible platform (which currently serves as a production hub for several other deepwater fields).