Pioneer Begins Production from Tomahawk & Raptor

Pioneer Natural Resources reports that its Tomahawk and Raptor fields in the western deepwater Gulf of Mexico began producing June 16, 2004. Pioneer developed the two discovery wells as subsea tie-backs to the Company's Falcon field facilities and established a new record for deepwater Gulf of Mexico operations completing development of the fields in ten months. Pioneer holds a 100% working interest and operates all four fields in the Falcon Corridor which are currently producing approximately 350 million cubic feet of gas and 1,000 barrels of condensate per day.

Tomahawk (East Breaks Block 623) and Raptor (East Breaks Block 668) are located 1.4 miles and 5.5 miles, respectively, from the Falcon subsea manifold in water depths ranging from 3,600 to 3,700 feet. The wells produce into a dual flowline system connecting the Falcon manifold to the Falcon Nest processing platform located 32 miles to the north on the Gulf of Mexico shelf. Falcon Nest is owned and operated by GulfTerra Energy Partners, L.P.

Scott D. Sheffield, Pioneer's Chairman and CEO, stated, "In just over three years, Pioneer has discovered and initiated production from four deepwater fields in the Falcon Corridor achieving tremendous returns. The Falcon field began production in March 2003, and the cost of its development was recovered through net cash flow from the field in March 2004. The Harrier field began production in February 2004 and paid out within 4 months in May 2004. We expect similar results with Tomahawk and Raptor and look forward to testing additional prospects with subsea tie-back potential in our exploration program planned for the second half of this year."