Smith Rock Geology
Smith Rock was formed primarily from volcanic activity. Located east of the Cascade Range, this area was once directly affected by the nearby volcanic mountains. Lava flowed into the area following many eruptions and filled the canyon that Smith rock is within. As lava built up, filled up paths and burnt new ones, the Crooked river was forced to create a new path winding path through the canyon.
The two major types of rock used by climbers are columnar basalt and welded tuff.
- Basalt – The gray basalt columns that line the outer canyon are created by lava flow from nearby Newberry Crater. In contrast to the rough tuff found on the primary cliffs within the canyon, basalt is often smoother. The columns of basalt in the upper cliffs of the outer canyon are divided by small to large cracks with create fun and exciting climbing opportunities.
- Tuff – The tuff found here is a type of rock created by ash within a volcano that is expelled from a vent while under extreme pressure and heat. Specifically, welded tuff is a pyroclastic rock that, as the name implies, welds together due to high temperatures. The tuff results in an often rough, uneven surface. Holes of varying sizes and small protrusions are common features.