BP looks at some really heavy oil in Alaska, and there is a LOT of it...
BP checks prospects for Ugnu site on Slope -
TECHNICAL DIFFICULTIES: Shallowest, heaviest of oil accumulations considered.
adn.com
By Petroleum News
Published: May 22, 2007
Last Modified: May 22, 2007 at 04:20 AM
BP Exploration (Alaska) Inc. has begun permitting for an extended Ugnu well test operation next year, a huge but troublesome and undeveloped oil field.
Ugnu is the shallowest and heaviest of North Slope oil accumulations. Oil companies have long known about Ugnu because their wells to deeper fields go through it.
The formation is not in production because technical problems of producing the cold, heavy oil that lies in unconsolidated formations have not been solved.
BP filed paperwork last week proposing to add to a work pad in the Milne Point field for testing Ugnu. Work this year would include gravel placement so that the gravel can compact and settle before an extended Ugnu well test operation next year, BP told state regulators.
BP told the state that pre-pilot well testing is expected to be an extended operation, the exact length of which is not now known.
GETTING AT ONE-FIFTH OF UGNU
BP talked to legislators about the planned Ugnu production test in late January.
BP's Milne Point resource manager, Scott Digert, told the state House Special Committee on Ways and Means that BP planned to spend about $25 million this year to do pilot tests for technology the company thinks could be used to produce the heavy oil at Ugnu.
Although there has been no production from Ugnu, heavy oil has been taken from the Schrader Bluff and West Sak fields, which are somewhat deeper below the ground.
Some 100 million barrels of heavy oil has been produced on the North Slope to date, compared to 15 billion barrels of light oil from such fields as Prudhoe Bay, Kuparuk River and Alpine.
An additional 100 million to 1 billion barrels of heavy production is possible.
Digert said the first Ugnu wells would use cold heavy oil production with sand technology, where oil is produced along with massive amounts of sand that come with it. The sand would be separated on the surface, he said, and the oil would have to be warmed before it could be transported with light oil.
Digert said BP thinks that with certain techniques it could get at some 20 percent of the Ugnu formation.
BP also plans to try other technologies in the future such as steam injection or other thermal recovery methods, but not the mining used in some shallow Canadian heavy oil fields. Digert said Ugnu can't be mined, because it's 2,500 to 3,500 feet below the service, and permafrost lies above it.
He said steam injection is also expected to be less effective on the Slope than in Canada because the Ugnu is colder and because of the challenge of getting steam down through the permafrost and warming up the colder oil. The North Slope rock is also different from Canada, where the oil sands are "blocky, very massive sands," he said, allowing for easy vertical movement. "Ours tend to have layers of shale within the sand that tend to block that vertical movement of oil." |
