About Acamarachi
Acamarachi is a stratovolcano rising to 6,023 meters (19,761 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
Acamarachi is located in Chile, within the Central Andean Volcanic Arc of the broader South America Volcanic Regions. Situated at 23.29° S, 67.62° W in the Southern Hemisphere, the volcano lies within a tropical climate zone. At 6,023 meters above sea level, Acamarachi 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
Acamarachi 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 Acamarachi, 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 dacite, an intermediate to silica-rich volcanic rock. This composition typically produces more viscous magma, leading to more explosive eruptions with ash columns and pyroclastic flows. Andesitic and dacitic magmas build pressure before erupting, which is why volcanoes with this rock chemistry are often associated with Plinian-style eruptions that can send ash tens of kilometers into the atmosphere and disrupt aviation across entire regions.
GVP Reference Summary
Acamarachi, a steep-sided andesitic-dacitic volcano, forms the highest peak in this part of the northern Andes. Also known as Cerro Pili, it is at the SSE end of a small volcanic complex that extends from the neighboring volcano Colachi to the NNW. A large lava dome is located on its N flank. A poorly preserved summit crater and the absence of youthful flank lava flows suggest that the volcano was largely constructed in pre-Holocene times, although the summit lava flows draping the upper cone were considered to be of Holocene age (González-Ferrán, 1995).
— Smithsonian Institution, Global Volcanism Program
0 Recorded Eruptions
No eruption records available for Acamarachi.
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Acamarachi
Is Acamarachi an active volcano?+
Acamarachi 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 Acamarachi?+
Acamarachi has a summit elevation of 6,023 meters (19,761 feet) above sea level. This makes it one of the tallest volcanoes in the world, comparable in height to some of the highest peaks in the Andes.
What type of volcano is Acamarachi?+
Acamarachi 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 Acamarachi located?+
Acamarachi is located in Chile, in the South America Volcanic Regions. More specifically, it lies within the Central Andean Volcanic Arc. Its exact coordinates are -23.292° latitude, -67.618° longitude.
Is it safe to visit Acamarachi?+
Acamarachi 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.
