Proterozoic schists By Matt Young December 29, 2014 12:00 MST Photograph by Jim Kocher. Photography contest, Honorable Mention. Painted Wall – Black Canyon of the Gunnison River, Montrose, Colorado, May, 1999; Kodachrome 64. Proterozoic schists intruded by pegmatite dikes (~1.25 Ga). Vertical relief is ~2,200 ft.
