The southern flank of Socorro is underlain by rocks of three distinct origins. On the lower flanks are basaltic rocks of the Lomas Coloradas unit that mostly erupted between about 150,000 and 70,000 years ago. The middle flanks contain trachyte and rhyolite pyroclastic flow deposits that were emplaced between about 540,000 and 370,000 years ago. The summit region, including Cerro Evermann (center horizon), consists of silicic rocks that were erupted between about 180,000 to at least 15,000 years ago.

Photo by Martha Marin, 1998 (Mexican Navy).

This image is made available under the Creative Commons BY-NC-ND 4.0 license terms.

Socorro