| This view is looking east from the Carroll Rim Trail toward
brightly colored hills and buttes consisting of John Day Formation. Sutton
Mountain is the ridge in the distance. The mountain consists of massive
layers of ancient lava flows that are called the Picture Gorge Basalt (part of the Columbia River Basalt Group) (Bishop and others, 2006). These
ancient volcanic rocks overlie the John Day Formation. The basalt flows
formed about 16 million years ago during the early volcanic eruptions that
produced massive lava flows that flooded much the Columbia River Plateau
region in eastern Oregon, Washington, and Idaho (Bestland and others, 2002). |
