Newberry Volcano, Oregon

Newberry Volcano, centered about 20 miles (32 km) southeast of Bend, Oregon, is among the largest Quaternary volcanoes in the conterminous United States. It covers an area in excess of 500 square miles (1,300 square km), and lava from it extends northward many tens of miles. The highest point on the volcano, Paulina Peak with an elevation of 7,984 feet (2,433 meters), is about 4,000 feet (1,219 meters) higher than the terrain surrounding the volcano. The gently sloping flanks, embellished by more than 400 cinder cones, consist of basalt and basaltic andesite flows, andesitic to rhyolitic ash-flow and air-fall tuffs and other types of pyroclastic deposits. At Newberry's summit is a 4- to 5-mile-wide (6-8 km) caldera that contains scenic Paulina Lake and East Lake. The caldera has been the site of numerous Holocene eruptions, mostly of rhyolitic composition, that occurred as recently as 1,400 years ago.