Global Volcanism Program | Image GVP-03200
The extensively eroded Sargents Ridge (right center), on the south side of Mount Shasta, is the oldest of four major edifices that were constructed following the collapse of ancestral Mount Shasta. The Sargents Ridge cone formed during the Pleistocene, less than 250,000 years ago. Mount Misery, which forms much of the upper part of the cone and overlies the Sargents Ridge cone, formed less than 130,000 years ago.
Photo by Lee Siebert, 1981 (Smithsonian Institution).