Unconventional Exploration Reaches: Alaska's North Slope

Abstract

North Slope Shale On the day last February that the US Geological Survey (USGS) came out with a report saying up to 2 billion bbl of oil could be produced from shale formations on the North Slope of Alaska, a company was already planning to drill on its 500,000-acre lease. That was a striking change at the agency where years separated the release of assessments and exploration in plays such as the Marcellus said David Houseknecht, a research geologist for the USGS and the lead author of the North Slope assessment. The explorers and the government geologists drew on similar sources to conclude the North Slope could be a likely spot for the next US shale exploration boom. While the USGS was working on its North Slope evaluation, geologists like Ed Duncan were looking for signs the rocks that were the source of oil that migrated over long periods into huge conventional reservoirs, such as the Prudhoe Bay, Kuparuk, and Alpine, could also be rich sources of oil. Using what he’d learned early in his career working the North Slope and later as a consultant for companies seeking new shale plays, Duncan and his wife Karen Duncan, formed a company called Great Bear Petroleum and put in a surprise bid at the December 2010 Alaska state lease sale. “I was stunned by the potential, with three of the most prolific oil source rocks and nobody was doing anything with them,” said Duncan, who is president and chief executive officer at Great Bear. At the time he told the story of how he came to explore the North Slope, Duncan was in Golden, Colorado, at a Weatherford lab studying the core samples collected from Great Bear’s test wells, the Alcor and the Merak, drilled in the summer of 2012. The wells near the gravel road that parallels the Trans-Alaska Pipeline penetrated all three source rock formations. The early evaluations were all in line with expectations but in late December he was just beginning to see the results of the tests of formations so rarely seen that a USGS geologist came out to examine them. Duncan hopes to drill a horizontal well, fracture it, and do a production test next, but: “As much as I would love to say here is the result, let’s go ahead with a fracture-flow test, that is not the case,” he said. “We are learning a tremendous amount every day,” Duncan said after 2 days in Golden. But critical tests on the rock properties indicating whether it could be effectively fractured would not come in until February. “My father would say there is plenty of wood to chop here,” he said.