SAN DIEGO, April 3, 2013 (GLOBE NEWSWIRE) -- Royale Energy, Inc. (Nasdaq:ROYL) reprints article. Copyright 2013, Environment and Energy Publishing LLC. Reprinted with permission. ANCHORAGE --Petroleum geologist Ed Duncan believes he's on the precipice of proving America's next monster shale oil play. Duncan, president and CEO of Great Bear Petroleum LLC, is betting big that Alaska's North Slope geology will yield bountiful untapped resources as vast as the unconventional oil plays at Texas' Eagle Ford and North Dakota's Bakken shale fields. He shocked the industry in 2010 when he scooped up 500,000 acres of Alaska state land leases in a region that international energy giants had long ago dismissed. The major oil companies were focused on conventional oil fields, like the lucrative resources at Prudhoe Bay and Kuparuk River along Alaska's northern shores. But Duncan and the oil industry veterans he's working with have their sights set on the lands just south of those fields. Specifically, they're focused on three layers of source rock that geologists say generated the large volumes of oil and gas that eventually migrated to Prudhoe Bay and Kuparuk. That source rock could contain up to 2 billion barrels of technically recoverable oil and up to 80 trillion cubic feet of natural gas, according to a 2012 U.S. Geological Survey report. The North Slope shales stretch from the Chukchi Sea on the west to the Arctic National Wildlife Refuge on the east. Last year, Great Bear took core samples and drilled two vertical flow test wells to acquire reservoir data on its leases. Duncan had hoped to begin horizontal drilling and fracking at the two sites in December, but the company's rig contract expired before the tests could proceed. Now Duncan and researchers at Great Bear's labs in Palo Alto, Calif., are poring over drilling data, rock cores and seismic records to determine their next step. Early test results verify that the source rock on their leases contains oil. The company also discovered a modest conventional oil field at the site. "We're not committed to drilling this summer," Duncan said in an interview. "But we have the permits in place if we choose to do so. We'll continue the technical evaluations as we have been doing."