A massive columnar jointed lava flow is exposed in a valley NE of Orizaba volcano. The roughly 530,000-year-old Calcahualco lava flow was erupted during the Torrecillas stage, from the first of three major volcanic edifices forming the volcano. The source vent of this flow is now buried.

Photo by Lee Siebert, 1998 (Smithsonian Institution).

This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.

Keywords: outcrop | stratigraphy | cooling joints | lava flow | geology

Pico de Orizaba