Andahua-Orcopampa

Geography & Climate

Andahua-Orcopampa is located in Peru, within the Central Andean Volcanic Arc of the broader South America Volcanic Regions. Situated at 15.42° S, 72.33° W in the Southern Hemisphere, the volcano lies within a tropical climate zone. Standing at 4,713 meters above sea level, Andahua-Orcopampa 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 cluster, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Andahua-Orcopampa 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 Peru near Andahua-Orcopampa, 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 trachyandesite / basaltic trachyandesite, 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

Andahua-Orcopampa has 4 recorded eruptions in the geological database, spanning from 2110 BCE to 1913 CE. These eruptions span roughly 4,023 years of volcanic history. The most recent eruption in 1913 CE places this volcano within the modern era of volcanological observation.

GVP Reference Summary

The Andahua-Orcopampa volcanic field in the Andahua (or Andagua) valley area, 20 km ENE of Nevados de Coropuna, is a large 60 x 60 km scoria cone and lava field. Known locally as the "Valley of the Volcanoes," the field lies in a series of deep NNW-SSE-trending, en-echelon valleys: Orcopampa, Andahua, and Ayo. The field contains youthful dominantly trachyandesitic cinder cones and lava flows that have destroyed buildings and may be only a few hundred years old. The area was reported to have been active during the time of the Incas and to have "become active again" in 1913. Lava flows have repeatedly dammed the Río Andagua valley, and an existing small lake was impounded by the youngest lavas.

— Smithsonian Institution, Global Volcanism Program