Oil production in some of the riskiest, highest-cost regions of North America is still thriving, even as the worst slump in a generation takes a bite out of U.S. shale. Onshore U.S. output is poised to drop 22 percent from last year through 2017, according to the Energy Information Administration. However, new volumes coming on stream from developments envisioned years ago in Canada’s oil sands and the U.S. Gulf of Mexico are limiting North America’s total production decline. Exxon Mobil Corp. is among companies bringing platforms online in the U.S. Gulf of Mexico from discoveries made in the past decade, which will help boost offshore output by 18 percent from last year to a record high in 2017, the EIA forecast this month. In the oil sands, developers including Canadian Natural Resources Ltd. are also expanding projects, leading to a 16 percent increase over the same period, Canadian Association […]