Minchinmavida volcanVolcán Minchinmávida volcano is an active basaltic-to-andesitic stratovolcano in southern Chile, west of Lago Reñihue. It was observed and in activity by C. Darwin in 1834 during his historic journey to the Galapagos Islands.
The massive glacier-coverd volcano is elongated in a NE-SW direction and and has a saddle-shaped summit with an elongated 3-km-wide caldera. A young crater is located on the ENE side of the complex.
2 major explosive eruptions had occurred about 3000 and 6000 years ago and produced significant tephra deposits extending to the east. Activity in historic times consisted of small explosive eruptions. The last eruption was from February to March 1835, produced a lava flow from a flank crater as well as lahars that reached the coast at Punta Chana.
When neighboring Chaitén erupted after a century-long repose interval in 2008, it was first believed that Minchinmávida was having a new eruption, since Chaitén was poorly known at that time.
Minchinmavida, along with Cerro Yanteles volcano further south, erupted in 1835 within a day of a magnitude 8.1 earthquake between 600 and 800 km away (Darwin, 1840).
- Michael Manga and Emily Brodsky (2006) "Seismic Triggering of Eruptions in the Far Field: Volcanoes and Geysers", Annu. Rev. Earth Planet. Sci 34: pp 263–91
- Darwin C. (1840) "On the connexion of certain volcanic phenomena in South America; and on the formation of mountain chains and volcanoes, as the effect of the same power by which continents are elevated." Trans. Geol. Soc. Lond. 5: pp 601–31
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