Mt Shasta

Shasta from the southwest. Shasta, 40 miles (65 km) south of the California-Oregon border is the second highest (14,161 feet, 4,317 m) mountain in the Cascade Range. The volcano is composed of four overlapping andesite eruptive centers all visible in the photograph. The oldest center is the Sargeants Ridge cone, located on the strongly eroded lower slopes of Shasta, was active about 450,000 years ago. Misery Hill, on the northwest flank of the Sargeants Ridge cone, was active between 15,000 and 20,000 years ago. Shastina, the prominent cone on the west flank of Shasta, was active around 9,200 years ago. The Hotlum cone is the youngest eruptive center and forms Shasta's summit and the north and northeast flanks. Hotlum cone was active only a few centuries ago. Photo by R. Forrest Hopson.     Source = Shasta, California

Mount Shasta, California
Geology 208 Cascade Volcano Report - Mt. Shasta