The SW part of Coatepeque caldera was formed about 57,000 years ago following the eruption of the roughly 16 km³ Congo biotite-bearing rhyolitic pumice fall and pyroclastic flow deposits. Plinian and phreatoplinian eruptions took place through a lake that formed in the NE part of the caldera that formed during the larger Arce eruption about 72,000 years ago.

Photo by Lee Siebert, 1999 (Smithsonian Institution).

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

Keywords: caldera

Coatepeque Caldera