The steep-sided caldera walls of Cosigüina volcano rise 500 m above a lake on the caldera floor. Inter-bedded gray lava flows and brownish pyroclastic deposits forming the pre-caldera stratovolcano are exposed in the far wall. Observers of Cosigüina prior to the catastrophic 1835 eruption described the volcano as being of low height, with a flat top, suggesting that the caldera was in existence prior to the eruption.

Photo by Jaime Incer.

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

Cosigüina