Imbabura

Geography & Climate

Imbabura is located in Ecuador, within the Northern Andean Volcanic Arc of the broader South America Volcanic Regions. Situated at 0.26° N, 78.18° W in the Northern Hemisphere, the volcano lies within a tropical climate zone. Standing at 4,609 meters above sea level, Imbabura towers above the alpine zone, where vegetation gives way to bare rock, snow, and ice for much of the year. The high elevation means the upper slopes experience significantly colder temperatures than surrounding lowlands. 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

Imbabura 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 Ecuador near Imbabura, 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 andesite / basaltic andesite, 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

Imbabura has 1 recorded eruption in the geological database, spanning from 5550 BCE to 5550 BCE.

GVP Reference Summary

Imbabura volcano rises to the north above scenic Laguna de San Pablo in the Interandean valley about 60 km N of Quito. The main edifice, Taita Imbabura ("Father Imbabura") forms the summit, with Huarmi Imbabura ("Imbabura's Son") forming a lateral lava-dome complex on the SW flank. Activity at the Pleistocene Imbabura I edifice constructed a large andesitic stratovolcano and ended prior to about 43,000 years ago with a major collapse that produced a debris avalanche that traveled 16 km N. Subsequent growth of the Imbabura II stratovolcano continued at least into the early Holocene and typically consisted of growth and collapse of large-volume dacitic lava domes. A major eruption about 25,000 years ago produced a debris avalanche and possible lateral blast and was followed by growth of the Huarmi Imbabura lava dome. Historical reports of eruptions consisted of only mudflows and rock slides.

— Smithsonian Institution, Global Volcanism Program