BHP Billiton Ltd. (BHP) said Thursday its Shenzi oil field in the Gulf of Mexico was exceeding nominal capacity of 100,000 barrels per day, and is achieving sustained rates of 120,000 barrels a day.

Shenzi started production in March this year, coming on stream three months ahead of schedule and within budget.

""Our primary goal during the early production phase of Shenzi was to safely achieve full design rates, which we did within 50 days of start-up. We have now been able to sustain rates significantly in excess of design capacity over the past two months," said J. Michael Yeager, chief executive of BHP Billiton Petroleum.

BHP is the owner-operator of Shenzi with a 44% stake. Hess Corp. and Repsol YPF S.A. each own 28%.

-By Elisabeth Behrmann, Dow Jones Newswires;

61-2-8272-4689 elisabeth.behrmann@dowjones.com