oil shale Green River Formation Green River Formation oil Green River Formation :en:Oil shale geology :en:Oil shale geology Green River Formation Oil shale geology - Wikipedia, the free encyclopedia Green River Formation Green River Formation English Green River Formation Green River Formation Green River Formation Green River Formation http://en.wikipedia.org/wiki/Oil_shale_geology Green River Formation oil Green River Formation Green River Formation en.wikipedia.org/wiki/Oil_shale_geology Green River Formation