Global Volcanism Program | Image GVP-08220
The SE wall of El Valle de Antón caldera rises up to 300 m above the flat caldera floor. The caldera was formed during major explosive eruptions about 1.1-1.3 million years ago. Post-caldera phreatomagmatic and phreatic eruptions related to a former lake filling the caldera floor have continued until the latest Pleistocene. More than 90 m of lake sediments were deposited on the caldera floor prior to draining of the lake through a breach in the SW caldera rim. The peak at the right center is Cerro la Silla.
Photo by Lee Siebert, 1998 (Smithsonian Institution).