Smith Rock State Park years ago, a large caldera was formed when overlying rock collapsed into an underground lava chamber. This created a huge amount of rock and ash debris that filled the caldera. That material solidified into rock, becoming Smith Rock tuff. Rhyolite flows intruded along faults in the Smith Rock Tuff. A half million years ago, basalt lava flows from nearby volcanoes covered the older tuff. More recently, the Crooked River cut its way through the layers of rock to create today's geographic features. Smith Rock itself is a -high ridge (above sea level) with a sheer cliff-face overlooking a bend in
Lava Lake (Oregon) Lava Lake (Oregon) Lava Lake lies in the Cascade Range about west-southwest of Bend in the U.S. state of Oregon. It is a close neighbor of Little Lava Lake, from which it is separated by solidified lava. Lava Lake is at an elevation of in the Deschutes National Forest. The lake covers to an average depth of . Lava Lake, Little Lava Lake, and other nearby lakes formed after lava flows from Mount Bachelor altered drainage patterns in the area. Solidified lava flows are visible along the shorelines of both lakes, and the volcanic peaks Broken Top and South Sister