"Tuff" Rock

These rock formations were formed from the volcanic ash of two eruptions of the Jemez (pronounced "HAY-mess") Volcano. Hundreds of times more violent than the Mount St. Helens eruption, the resulting layer of ash was a thousand feet thick and covered 400 square miles. When the volcanic ash compacted over time it formed a pinkish, crumbly rock called "tuff". Weathering of this soft rock has formed many unusual formations like those seen in the image. Imaged in Bandelier National Monument, NM in August 2000.