Global Volcanism Program

Volcán Copahue is an elongated composite cone constructed along the Chile-Argentina border within the 6.5 x 8.5 km wide Trapa-Trapa caldera that formed between 0.6 and 0.4 million years ago near the NW margin of the 20 x 15 km Pliocene Caviahue (Del Agrio) caldera. The eastern summit crater, part of a 2-km-long, ENE-WSW line of nine craters, contains a briny, acidic 300-m-wide crater lake (also referred to as El Agrio or Del Agrio) and displays intense fumarolic activity. Acidic hot springs occur below the eastern outlet of the crater lake, contributing to the acidity of the Río Agrio, and another geothermal zone is located within Caviahue caldera about 7 km NE of the summit. Infrequent mild-to-moderate explosive eruptions have been recorded since the 18th century. Twentieth-century eruptions from the crater lake have ejected pyroclastic rocks and chilled liquid sulfur fragments.

Global Volcanism Program

World map showing location of the volcanoes and countries represented

Timeline of eruption history based on the Global Volcanism Program

Holocene volcanoes. Source: Olivier Santoni (CERDI) using data from the

Global Volcanism Program

Global Volcanism Program

Global Volcanism Program

Global Volcanism Program

Volcanoes of the World - Global Volcanism Program

Global Volcanism Program, West Mata in 2023

Global Volcanism Program