Oil traders scrambling to secure crude in the U.S. Midwest have pushed North Dakota's Bakken to a near premium for the first time in two years, a rally stoked by record refinery runs and an unprecedented slump in Canadian imports. Yet some traders say the surprising strength emerging from opaque physical crude markets in the heartland of the fracking boom also points to a more important, lasting factor: declining production of Bakken crude, a long-anticipated but as yet unproven twist in the shale revolution. source: reuters