Llaima

Geography & Climate

Llaima is located in Chile, within the Southern Andean Volcanic Arc of the broader South America Volcanic Regions. Situated at 38.69° S, 71.73° W in the Southern Hemisphere, the volcano lies within a temperate climate zone. At 3,125 meters above sea level, Llaima rises above the surrounding terrain into montane or subalpine conditions. The elevation creates distinct ecological zones along its flanks, from forested lower slopes to exposed rocky terrain near the summit. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Llaima sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Chile near Llaima, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is basalt / picro-basalt, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Llaima has 58 recorded eruptions in the geological database, spanning from 7410 BCE to 2009 CE. The most powerful recorded event was a paroxysmal eruption with devastating regional consequences in 6880 BCE, reaching VEI 5 on the Volcanic Explosivity Index. Notable eruptions include 2008 CE (VEI 3), 1955 CE (VEI 3), 1945 CE (VEI 3). With an average interval of roughly 162 years between eruptions over a span of 9,418 years, this is one of the more frequently active volcanoes in the database. This persistent activity suggests a robust and well-supplied magma system beneath the volcano. With eruptive activity as recently as 2009 CE, Llaima remains an actively monitored volcano.

Significance

With a maximum recorded VEI of 5, Llaima has demonstrated the capacity for paroxysmal eruptions comparable to the 1980 eruption of Mount St. Helens. Eruptions of this scale can devastate areas within 20-30 kilometers and produce ash fall that disrupts aviation and agriculture across hundreds of kilometers. Its 58 recorded eruptions make it one of the most prolific volcanoes in the entire global volcanic record, reflecting an exceptionally persistent magma supply system that has sustained near-continuous eruptive activity over millennia. Given its recent activity, Llaima is closely monitored by geological survey organizations to provide early warning of future unrest.

GVP Reference Summary

Llaima, one of Chile's largest and most active volcanoes, contains two main historically active craters, one at the summit and the other, Pichillaima, to the SE. The massive, dominantly basaltic-to-andesitic, stratovolcano has a volume of 400 km3. A Holocene edifice built primarily of accumulated lava flows was constructed over an 8-km-wide caldera that formed about 13,200 years ago, following the eruption of the 24 km3 Curacautín Ignimbrite. More than 40 scoria cones dot the volcano's flanks. Following the end of an explosive stage about 7200 years ago, construction of the present edifice began, characterized by Strombolian, Hawaiian, and infrequent subplinian eruptions. Frequent moderate explosive eruptions with occasional lava flows have been recorded since the 17th century.

— Smithsonian Institution, Global Volcanism Program