About Colachi
Colachi is a stratovolcano rising to 5,631 meters (18,475 feet) in Chile's South America Volcanic Regions. No historical eruptions have been recorded, though the volcano is classified based on geological evidence of past activity.
Geography & Climate
Colachi is located in Chile, within the Central Andean Volcanic Arc of the broader South America Volcanic Regions. Situated at 23.24° S, 67.64° W in the Southern Hemisphere, the volcano lies within a tropical climate zone. At 5,631 meters above sea level, Colachi reaches well into the permanent snow and ice zone. Glaciers and snowpack on the upper slopes create the potential for lahars — destructive volcanic mudflows — during eruptions, as heat rapidly melts ice and snow. 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
Colachi 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 Colachi, 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.
GVP Reference Summary
Colachi is a andesitic-dacitic stratovolcano that was constructed on an uplifted block of welded ignimbrites. The most recent activity produced pristine silicic lava flows of probable Holocene age, the largest of which covers a 7 km2 area on the saddle between Colachi and the neighboring volcano of Acamarachi (de Silva and Francis, 1991). A smaller flow was erupted on the W flank. The closely spaced Colachi and Acamarachi volcanoes represent different magmatic systems (Gardeweg 1993, pers. comm.).
— Smithsonian Institution, Global Volcanism Program
0 Recorded Eruptions
No eruption records available for Colachi.
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Colachi
Is Colachi an active volcano?+
Colachi is classified as active based on credible evidence of past eruptions. Although its last known eruption was in prehistoric times, volcanologists consider it capable of erupting again.
How high is Colachi?+
Colachi has a summit elevation of 5,631 meters (18,475 feet) above sea level. At 5,631 meters, it stands taller than Mount Rainier (4,392m) and is among the world's major volcanic peaks.
What type of volcano is Colachi?+
Colachi is classified as a Stratovolcano. Stratovolcanoes (also called composite volcanoes) are steep, conical volcanoes built up by many layers of hardened lava, tephra, and volcanic ash. They are among the most common and dangerous types, known for explosive eruptions.
Where is Colachi located?+
Colachi is located in Chile, in the South America Volcanic Regions. More specifically, it lies within the Central Andean Volcanic Arc. Its exact coordinates are -23.236° latitude, -67.645° longitude.
Is it safe to visit Colachi?+
Colachi can generally be visited, but as with any volcano, visitors should check local conditions and any advisory notices before traveling. Chile may have specific regulations for accessing volcanic areas. Guided tours are often the safest and most informative way to experience a volcano.
