Responding about an inch per year to crustal uplift that raised the modern Rockies, western Colorado’s Gunnison River has cut a deep, magnificent canyon here, 2,250 feet into a slab of very hard, 1.7-billion-year-old (Precambrian) gneiss and schist. The metamorphic rock’s rigidity and erosion resistance keep the gorge unusually steep-walled. For scale, those are mature trees down there. Chicago’s Sears Tower easily would fit in the bottom to middle of the view, with another 800 feet to spare below the canyon rim. Veins of pegmatite and stains of iron oxides color the walls of this part of the Black Canyon, whose bottom seldom sees direct sunlight in many places. Twilight, or in this case nearly overcast storm light from an approaching line of shallow thunderstorms, helps photography in deep gorges by distributing light more evenly and reducing dynamic range. Short time exposures in such dark conditions help to pull the natural colors of the rocks.
11 NE Montrose, CO (5 Oct 18) Looking WSW
38.5811, -107.7183Black Canyon in the Light: Painted Wall
Responding about an inch per year to crustal uplift that raised the modern Rockies, western Colorado’s Gunnison River has cut a deep, magnificent canyon here, 2,250 feet into a slab of very hard, 1.7-billion-year-old (Precambrian) gneiss and schist. The metamorphic rock’s rigidity and erosion resistance keep the gorge unusually steep-walled. For scale, those are mature trees down there. Chicago’s Sears Tower easily would fit in the bottom to middle of the view, with another 800 feet to spare below the canyon rim. Veins of pegmatite and stains of iron oxides color the walls of this part of the Black Canyon, whose bottom seldom sees direct sunlight in many places. Twilight, or in this case nearly overcast storm light from an approaching line of shallow thunderstorms, helps photography in deep gorges by distributing light more evenly and reducing dynamic range. Short time exposures in such dark conditions help to pull the natural colors of the rocks.
11 NE Montrose, CO (5 Oct 18) Looking WSW
38.5811, -107.7183