Oklahoma City-based Continental Resources testing reveals more Bakken oil

Monday's announcement helps support Continental's estimates.

“From an exploration standpoint, it's very gratifying to see a lot of effort and a lot of science translate into a positive outcome here,” Stark said. “The old adage is that good fields continue to get better. That really seems to be the case with the Bakken.”

Stark said current technology should allow recovery of 3 to 5 percent of the total oil, or 27 billion to 45 billion barrels.

Continental's stock price gained $2.90, or 4.2 percent, Monday to close at $71.60 on the New York Stock Exchange.

Analyst Gail Nicholson praised the Charlotte 3-22H well's early results.

“We think this is a very positive well. It is in line or a little bit ahead of our expectations,” said Nicholson, an analyst with KLR Group in Tampa, Fla. “We still think we need to get a little more production history from the well, but if they can continue to have success and further delineate these lower benches (layers), it will add incremental value to the company as well as the entire Williston Basin.”

Continental's reserve estimates in the Bakken generally have been higher than most other evaluations.