BP finds huge oil field deep beneath the Gulf of Mexico

— -- British energy producer BP on Wednesday reported a "giant" oil discovery in the Gulf of Mexico that's likely to spur more excitement about the region's potential.

The well, 250 miles southeast of Houston, was discovered after BP drilled one of the world's deepest exploration wells. It went down 35,000 feet, a distance on par with the cruising altitude of many domestic flights.

BP hasn't released specifics on the size of the field. But if it turns out to be truly "giant," it'll contain more than 500 million barrels of recoverable oil, according to definitions by the U.S. Energy Information Administration. The last giant discovered in the deepwater Gulf of Mexico was Thunder Horse in 1999. It's also operated by BP.

The new find — which will produce for the domestic U.S. market — is among 18 oil discoveries since 2000 in ultra-deep water off the coast of Texas and Louisiana, says Leta Smith, a director of IHS Cambridge Energy Research Associates.

One of those included another massive find nearby by BP in the so-called Kaskida field in 2006. That two big fields were discovered in the same region, along with others, signals the potential for more in the deep water. Development of the new find will be closely watched by others "to see how it plays out," Smith says.

The new discoveries will also drive an increase in domestic oil production for the first time in decades, she says. BP won't say when its new finds will start producing oil. Thunder Horse took nine years to come online.

While a big find, the field's potential production won't constitute more than a "drop in the bucket" when it comes to U.S. oil consumption, says Perry Fischer, editor of trade journal World Oil in Houston. The U.S. consumes 20 million barrels of oil a day.

Shares of BP, the biggest oil and gas producer in the Gulf of Mexico and the fifth-largest publicly traded oil producer in the world, rose 4% to $52.53 Wednesday.

The next step for BP is to dig more wells to ascertain the potential size of the find, says BP spokesman Daren Beaudo. That alone is likely to take several years. Technical challenges to extract the oil will be huge, says analyst Smith. Those include managing the depth of the well and temperatures and pressures.