Pioneer Natural Resources USA Inc., a subsidiary of Pioneer Natural Resources Co., Dallas, (NYSE: PXD) has closed the sale of certain deepwater Gulf of Mexico assets to Marubeni Offshore Production (USA) Inc., a subsidiary of Marubeni Corp., Tokyo, for US$1.3 billion cash before normal closing adjustments which are currently estimated to be US$140 million. Pioneer expects to record an after-tax gain of approximately US$425- to US$475 million. The transaction includes Pioneer's interests in three producing projects (Falcon Corridor, Devils Tower and Canyon Express), two potential development projects (Ozona Deep and Thunder Hawk) and 87 exploration blocks. One exploration block was removed from the sale to Marubeni due to a third-party exercise of a preferential right to purchase the block. The properties had a net daily production of some 38,000 barrels of oil equivalent in December. Pioneer expects to use a portion of the proceeds to initiate buy back of the remaining US$359 million of shares authorized under its previously announced US$1-billion share-repurchase program. Proceeds will also be used to reduce short-term debt and fund a portion of its 2006 capital budget, which is focused primarily on North American onshore development and lower-risk resource plays.