W&T gauges Ship Shoal Mahogany deep subsalt pay
A subsalt deeper pool discovery in Mahogany field on the Gulf of Mexico shelf is producing at rates of 3,030 b/d of oil and 5.6 MMcfd of gas from below 17,200 ft, said W&T Offshore Inc., Houston.
The Ship Shoal 359 A-14 well is producing with a flowing tubing pressure of 9,400 psi surface pressure from the targeted subsalt T sand, the deepest sand discovered in Mahogany field, the company said.
Mahogany field has additional pay identified in the M, N, and O sands, all of which represent future reserve additions, W&T said. The A-14 well also penetrated a thicker than expected interval in the P sand, the field’s main pay, that will also serve as a future recompletion.
The A-14 well logged a combined total of more than 370 ft of net oil pay, with the T sand accounting for 108 feet of the total net pay.
Success from the A-14 T sand will lead to further drilling in 2014 to exploit the four newly discovered oil sands that were encountered in the A-14 well. W&T holds a 100% working interest in the field.
Mahogany, discovered by the former Phillips Petroleum Co., went on production in December 1996 (OGJ, Aug. 17, 1998, p. 116).
Tracy Krohn, W&T’s chairman and chief executive officer, said, “Our exploration team utilized our subsalt imaging technology to identify and deliver this subsalt discovery which is a deep shelf exploration extension to our producing Mahogany field.
“We found a very high quality oil sand in the T sand reservoir with great flow characteristics. Another key value driver on this project is our ability to produce this discovery immediately through our existing infrastructure at Mahogany. We are evaluating additional targets in this highly prolific field based upon our continuing success and look forward to our next exploratory well at Mahogany, the A-15 well, which should begin drilling in September.”
The Mahogany platform rig is handling a major recompletion of the A-4 well, designed to bring a behind pipe P sand interval into production at an expected rate of 1,000 b/d of oil equivalent net of royalties to W&T, with production anticipated in August or September.
Following the A-4 recompletion W&T expects to spud the A-15 subsalt exploratory well, a multihorizon attempt that is anticipated to encounter multiple stacked oil sand targets.
The A-15 well is scheduled to reach total depth near yearend or early 2014. Its target IP rate is 1,390 boe/d net of royalty to W&T. The unrisked reserve potential associated with the A-15 well is estimated to be 1.8-6.2 million boe.
W&T Offshore acquired Apache Corp.’s interest in Mahogany field effective Jan. 1, 2008 (OGJ Online, Dec. 27, 2007)