A photo of Mount Scott

This zoomed in view shows Mount Scott on the right, Sentinel Rock in the middle, and the massive cliff of Skull Rock on the left. Mount Mazama began to form about a million years ago. The eastern half of Mount Mazama is built on older flows and domes that formed 600,000 to 700,000 years ago (Bacon, 1990). The great volcano was part of a complex volcanic area consisting of shields (volcanoes built up of lava flows), cinder cones (volcanoes built up of ash and cinder), and stratovolcanoes (the combination of intermittent layers of lava flows and ash and cinder deposits). Lava and ash erupted from numerous vents at different times, but the result was the buildup of a great mountainous volcano, similar to other great volcanoes in the Cascade Range.