What three states are covered by the volcano range including the North Cascades?
Cascades Volcano Observatory The David A. Johnston Cascades Volcano Observatory is the volcano observatory that monitors volcanoes in the northern Cascade Range. Its territory covers Oregon, Washington, and Idaho. The Cascade range's southernmost reaches extend into Northern California, and Cascade volcanoes south of the Oregon-California border—such as Mt. Shasta—previously fell into CVO's jurisdiction. However, as of February 2012, these volcanoes fall under the jurisdiction of the newly formed California Volcano Observatory (CalVO), based in Menlo Park, CA which monitors and researches volcanic activity throughout California and Nevada.
Medicine Lake Volcano Medicine Lake Volcano is a large shield volcano in northeastern California about 50 km northeast of Mount Shasta. The volcano is located in a zone of east-west crustal extension east of the main axis of the Cascade Volcanic Arc and the Cascade Range. The 1 km thick shield is 35 km from east to west and 45 to from north to south, and covers more than 2000 km2 . The underlying rock has downwarped by 0.5 km under the center of the volcano. The volcano is primarily composed of basalt and basaltic andesite lava flows, and has a 7 by caldera at the center.