Telluride and the Black Canyon of the Gunnison
Wherein Moominmama enjoys more of the Colorado spring at high elevation... The rocky peaks of Telluride and the steep walls of the Black Canyon of the Gunnison are separated by a couple hours' drive, but they are formed by a similar process: a combination of tectonic uplift, volcanic activity and erosion. While one can see the mountains of the Uncompahgre for miles, the Black Canyon is a geological feature that springs itself on you: a gorge with sheer cliffs over 2,700 feet deep. It narrows to as much as 40 feet at the bottom and 1,000 feet at the rim. You don't see it until you're at the edge. One of the interesting features of the gorge is its striped cliff faces. Most of the rock here is metamorphic rock: a dark grey gneiss and schist, (why this is called the Black Canyon). But tectonic uplift pushed these 1.8 billion-year-old rocks over a volcanic hotspot and magma flowed up filling any cracks. The magma then cooled over millions of years, allowing large crystals ...