Pomerape in the context of Cordillera Occidental (Bolivia)

The Cordillera Occidental or Western Cordillera of Bolivia is part of the Andes (that is also part of the American Cordillera), a mountain range characterized by volcanic activity, making up the natural border with Chile and starting in the north with Juqhuri and ending in the south at the Licancabur volcano, which is on the southern limit of Bolivia with Chile. The border goes through the innominated point located at two-thirds of elevation of Licancabur's northeastern slope at the southwesternmost point of Bolivia at 22° 49' 41" south and 67° 52' 35" west. The climate of the region is cold and inadequate for animal and plant life. Its main feature is its ground, in which are large quantities of metallic minerals including gold, silver, copper, and others. The range consists of three sections:

• The northern section, in which you can find the highest peaks in Bolivia, tallest of which is the volcano Sajama at 6,542 meters. Sajama is perennially covered in snow. It contains the volcanoes Pomerape and Parinacota (called Payachata collectively), the latter being a dormant volcano with a cone of snow similar to Mount Fuji in Japan.
• The central section, situated between Uyuni and Coipasa. Its most prominent summit is the Ollagüe (Ullawi) volcano on the border with Chile.
• The southern section, characterized by volcanic activity and by having sandstorms and fog, taking into account Licancabur, which is 5,920 meters high (but only two-thirds of the northeastern slope of the volcano belong to Bolivia up to 5415 meters). The lakes Laguna Colorada and Laguna Verde can be found on Licancabur, so named because of their respective colors.

Parinacota (in Hispanicized spelling), Parina Quta or Parinaquta is a dormant stratovolcano on the border of Bolivia and Chile. Together with Pomerape it forms the Nevados de Payachata volcanic chain. Part of the Central Volcanic Zone of the Andes, its summit reaches an elevation of 6,380 metres (20,930 ft) above sea level. The symmetrical cone is capped by a summit crater with widths of 1 kilometre (0.62 mi) or 1,000 metres (3,300 ft). Farther down on the southern slopes lie three parasitic centres known as the Ajata cones. These cones have generated lava flows. The volcano overlies a platform formed by lava domes and andesitic lava flows.

The volcano started growing during the Pleistocene and formed a large cone. At some point between the Pleistocene and the Holocene, the western flank of the volcano collapsed, generating a giant landslide that spread west and formed a large, hummocky landslide deposit. The avalanche crossed and dammed a previously existing drainage, impounding or enlarging Lake Chungará; numerous other lakes now forming the headwaters of the Rio Lauca sprang up within the deposit. Volcanic activity rebuilt the cone after the collapse, cancelling out the collapse scar.

Payachata or Paya Chata (Aymara pä, paya two, Pukina chata mountain, "two mountains") is a north–south trending complex of potentially active volcanos on the border of Bolivia and Chile, directly north of Chungará Lake. The complex contains two peaks, Pomerape to the north and Parinacota to the south. On the Bolivian side the volcanoes are located in the Oruro Department, Sajama Province, Curahuara de Carangas Municipality, and on the Chilean side they lie in the Arica y Parinacota Region, Parinacota Province.

According to helium surface dating, Parinacota has erupted within the last 2000 years, while Pomerape is Pleistocene.