Dallas, Texas - Venari Resources LLC said it had made a major oil discovery at its Shenandoah prospect in the Gulf of Mexico. The deepwater oil exploration and production company said its Shenandoah-2 well was drilled in about 5,800 feet of water to a total depth of 31,405 feet.

Venari said that it and its partners - Anadarko Petroleum Corp., ConocoPhillips, Cobalt International Energy, and Marathon Oil Corp. - are evaluating the results and assessing its production potential.

"The Shenandoah appraisal well has confirmed the field to be a major discovery with excellent-quality reservoir and fluid properties, and significant resource potential," Venari Chief Executive Officer Brian Reinsborough said. "This well has the potential of becoming one of the largest oil discoveries ever made in the deepwater Gulf of Mexico and demonstrates Venari's capability to explore for significant resources in the emerging areas of the deepwater gulf."

The announcement came the day before the US Interior Department's Bureau of Ocean Energy Management was to hold a lease sale in New Orleans that will make nearly 39 million offshore acres available for oil and gas development.

The sale follows one for more than 20 million acres in November and one of nearly 39 million acres last June.