Big Bend National Park – West Side – Tuff Canyon
Tuff Canyon in Big Bend National Park is an easy day hike down into the bottom of a canyon consisting primarily of a soft rock made out of volcanic tuff (volcanic ash). The volcanic ash was deposited by hot pyroclastic flows (like Pompeii) millions of years ago. Boulders in the canyon walls were carried along by those pyroclastic flows.
Tuff Canyon has been primarily carved by thousands of years of rainfall in the form of flash floods. Some of the boulders on the canyon floor came from miles away.
From the car you walk left towards Cerro Castellan Mountain (or butte) to the floor of the canyon. Cerro Castellan is a stack of pyroclastic rock layers capped by a rhyolite lava dome. Here you go right and walk north east up the canyon with Cerro Castellan behind you. Water under the surface allows the growth of small trees.
The normal path is to walk along the canyon floor until you get to the magma (basaltic lava) and then turn back. I was curious about what was above so I climbed up the magma and kept on going. This ended in a dead end with a small pool but there was a way out on the right side that did not seem difficult so I climbed out of the canyon and found my way back.
