Continental Resources Inc. is touting production results from a Three Forks test well suggesting that a lot more oil may be had from the massive Bakken petroleum system of North Dakota and Montana.
The petroleum system includes multiple Three Forks layers or “benches” that underlie the Bakken field. The Charlotte 3-22H is said to be the first horizontal well ever to test the deeper third bench.
“This could be a real game-changer,” Harold Hamm, Continental’s chairman and chief executive officer, said in a Dec. 3 statement.
Earlier this year the Oklahoma-based E&P independent dramatically increased the Bakken petroleum system’s estimated in-place oil by 57 percent, from 577 billion to 903 billion barrels of oil equivalent, based primarily on numerous oil-saturated core samples taken from wells at various locations within the Three Forks.
But Continental declined to say at the time how much of that resource it thought could be commercially recovered, largely because of a lack of well performance data. Continental estimated in late 2010 that the Bakken would yield 24 billion boe on 577 billion boe of in-place resource, based on the level of technology at the time. And that estimate stands today, despite strong results from its recently completed Charlotte 3-22H.
24 billion still stands
Jack Stark, Continental’s senior vice president of exploration, told Petroleum News Bakken that while the Charlotte 3-22H does help support the previous estimate of 903 billion boe in place, it’s only one new piece of data and “does not materially change” the company’s earlier 24 billion boe recoverable estimate.
“The significance of the Charlotte 3-22H success is that it is another step in our efforts to assess the productivity of the lower Three Forks reservoirs, and determine if they increase the ultimate recoverable reserve potential of the Bakken field,” Stark said in an email. “This is very encouraging but (we) will need more time and wells to prove (this) one way or the other.”
Charlotte 3-22H had been producing for 15 days when the company released information on the well’s early performance. And if it continues to perform in line with the Three Forks second bench Charlotte 2-22H, it will be the first well to establish commercial production in the third bench, Hamm said.
“We’re very pleased with the initial performance of the Charlotte 3-22H,” he added.
Initial IP 953 boe per day
The Charlotte 3-22H flowed at 953 boe per day at 1700 psi on a 28/64 choke in its initial one-day test period, Continental said, noting that its performance compared favorably with first and second bench wells of the Three Forks.
Located in McKenzie County, N.D., the well was drilled to a total depth of 21,324 feet, including a 9,701-foot lateral section, and was completed with Continental’s standard 30-stage fracture stimulation design.
The third bench Charlotte 3-22H is the first well in a 14-well program that the company plans to complete by year-end 2013 to test productivity of the second, third and fourth benches of the Three Forks over a broad area of the play.
The 1280-acre Charlotte unit is the first unit in the Bakken field to have wells producing from three separate horizons — the Middle Bakken and the second and third benches of the Three Forks.
Three Forks not in earlier estimates
Recoverable estimates for the Bakken petroleum system have varied widely dating back to the 1950s. In April 2008, the U.S. Geological Survey estimated the amount of oil that could be recovered using current technology at 3-to 4.3 billion barrels, with a mean of 3.65 billion. The state of North Dakota also released a report in April 2008 estimating there were 2.1 billion barrels of technically recoverable oil in the Bakken. Another estimate placed the recoverable figure at 18 billion barrels.
However, earlier studies, including the 2008 USGS report, did not include estimates from the Three Forks and its various benches. But the USGS is expected to release an updated report next year that includes the Three Forks, which many believe will, at a minimum, double the agency’s earlier recoverable estimates.
Core samples that provided Continental with the necessary data to raise its in-place oil estimate to 903 billion barrels are from wells widely dispersed within the Bakken petroleum system, in an area measuring about 120 miles by 60 miles.
Continental’s 24 billion barrel recoverable estimate was based on oil in place in just the Bakken and first bench of the Three Forks. With the addition of oil found in the lower Three Forks benches, the company pushed its in-place estimate to the 903 billion barrel level.
Estimates of 4-5% recovery
And though Continental has been reluctant to discuss recoverable estimates that likely will vary from the company’s official 24 billion barrels, a recovery rate of 4 or 5 percent for the additional 326 billion barrels of in-place oil seems reasonable, Stark said on the sidelines of last May’s Williston Basin Petroleum Conference in Bismarck, N.D.
“This is total speculation, but it is based on the fact that there is more oil in place,” he said.
At 4 percent, the recovery on the 903 billion barrels of in-place oil estimate would be about 36 billion barrels; and at 5 percent, recovery would be roughly 45 billion barrels.
Continental, the Bakken’s largest leaseholder and a leading producer, has been a pioneer in the discovery and development of the Three Forks reservoir in the Bakken field. It was the first to demonstrate incremental reserves from the first bench in 2008 and from the second bench in 2011. Establishing production from the third bench is considered yet another significant milestone in the growth of the company’s assets in the world-class Bakken oil field.
