Mariner Announces Sale of Aconcagua Field

Mariner Energy, Inc. announced the sale of its interests in the Aconcagua Field and the Canyon Express Pipeline System for $51 million to Nippon Oil Exploration USA, LTD. and Pioneer Natural Resources Company. The Aconcagua field (Mississippi Canyon 305) is one of three deepwater natural gas fields being jointly developed as a result of the Canyon Express Pipeline System and is located 150 miles southeast of New Orleans. Closing is scheduled to occur on November 1, 2001, subject to satisfactory completion of customary due diligence.