Pomerape is a

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

lying on the border of northern

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

and

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

(

Oruro Department Oruro (; Quechua: ''Uru Uru''; Aymara: ''Ururu'') is a department of Bolivia, with an area of . Its capital is the city of Oruro. According to the 2012 census, the Oruro department had a population of 494,178. Provinces of Oruro The depar ...

Sajama Province Sajama is a province in the northwestern parts of the Bolivian Oruro Department. Location ''Sajama'' province is one of the sixteen provinces in the Oruro Department. It is located between 17° 39' and 18° 39' South and between 67° 38' and 68° ...

, Curahuara de Carangas Municipality). It is part of the Payachata complex of volcanoes, together with

Parinacota Volcano Parinacota (in Hispanicized spelling), Parina Quta or Parinaquta is a dormant stratovolcano on the border of Chile and Bolivia. Together with Pomerape it forms the Nevados de Payachata volcanic chain. Part of the Central Volcanic Zone of the ...

to the south. The name "Payachata" means "twins" and refers to their appearance. It hosts

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

s down to elevations of , lower on the northern slope. Pomerape is a complex of

lava dome In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on ...

s, accompanied by

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 u ...

which were emplaced atop of the domes. It was active about 200,000 years ago. The lava domes formed first and were later buried by the actual volcanic cone, which unlike the rhyolitic-dacitic domes is formed by hornblende andesite. The "Chungará Andesites" and lava dome complex of Parinacota were laid down at this time. Pomerape is associated with an adventive vent that has erupted mafic magmas. The main cone was last active 106,000 +- 7,000 years ago, the adventive vent is dated to 205,000 ± 24,000 years ago. Climbing the volcano is alpine grade PD by the east ridge. Harder routes exist on the south face, sometimes on 50+ degree snow/rubble slope. For these routes a camp can be established at at the saddle between Parinacota and Pomerape. Depending on the season, the main difficulty can be penitentes (tall ice-blade needles), which make the ascent physically difficult or impossible.

References

* (includes Pomerape) Volcanoes of Arica y Parinacota Region Stratovolcanoes of Chile Subduction volcanoes Volcanoes of Oruro Department Mountains of Chile Pleistocene stratovolcanoes Polygenetic volcanoes Potentially active volcanoes Bolivia–Chile border International mountains of South America Six-thousanders of the Andes {{AricaParinacota-geo-stub

See also

References