Firura is an extinct

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

of the Central

Andean Volcanic Belt The Andean Volcanic Belt is a major volcanic belt along the Andean cordillera in Argentina, Bolivia, Chile, Colombia, Ecuador, and Peru. It is formed as a result of subduction of the Nazca plate and Antarctic plate underneath the South Americ ...

, located in the

Arequipa Region Arequipa () is a department and region in southwestern Peru. It is the sixth largest department in Peru, after Puno, Cuzco, Madre de Dios, Ucayali, and Loreto, its sixth most populous department, and its eleventh least densely populated dep ...

of southern

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

. Together with

Sara Sara Sara Sara is a volcano lying between Lake Parinacochas and the Ocoña River in Peru. It is situated in the provinces of Parinacochas and Paucar del Sara Sara. The volcano formed during the Pleistocene during four different stages of volcan ...

, Solimana and

Coropuna Coropuna is a Volcano#Dormant, dormant Complex volcano, compound volcano located in the Andes mountains of southeast-central Peru. The upper reaches of Coropuna consist of several snow field, perennially snowbound conical summits, lending it th ...

it forms one of the Central Andean volcanoes. It is in the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

, north of the Pucuncho Basin.

Description

Two domes form the Firura volcano, which has a low relief of and grew on top of older

ignimbrite Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surrou ...

Lava flows Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or unde ...

and

stratovolcanoes A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a ...

form a long field. Aside from the main summit Firura, there also are Soncco Orcco (), Jahsaya () and separating Firura from Solimana Antapuna (). The complex has generated

basaltic Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron ( mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% ...

basaltic andesite Basaltic andesite is a volcanic rock that is intermediate in composition between basalt and andesite. It is composed predominantly of augite and plagioclase. Basaltic andesite can be found in volcanoes around the world, including in Central Ameri ...

lava flows that reach down into inhabited areas, as well as an

resulting from the collapse of the ancient crater. A collapse of the crater was also responsible for the formation of a landslide dam in the

Cotahuasi River Cotahuasi is a town in Southern Peru, capital of the province La Unión in the region of Arequipa Arequipa (; Aymara language, Aymara and ), also known by its nicknames of ''Ciudad Blanca'' (Spanish for "White City") and ''León del Sur'' ( ...

valley. The date of the last volcanic activity is

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

, but it does not appear to be a significant hazard and is classified as a very low-risk volcano. Much of the southern side of the volcano above altitude is covered with perennial snow. A small

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

(>) is found on the southern summit of Firura and reaches down to . This glacier appears to be located above the local

equilibrium line altitude Glaciology (; ) is the scientific study of glaciers, or, more generally, ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, clim ...

. Firura has well preserved

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

systems. A major moraine system with a relief of was left by the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered m ...

, although expansion of glaciers on the northern flank was constrained on a high plateau. The prevalent aridity of the climate impedes the degradation of these moraines.

References

{{Andean volcanoes Volcanoes of Peru Mountains of the Department of Arequipa Andean Volcanic Belt Five-thousanders of the Andes Pleistocene volcanoes Pleistocene Peru