It lies on the western margin of the Altiplano high plateau, on top of older volcanic and sedimentary units.

Taapaca has mainly erupted dacite, in the form of numerous lava domes, although an andesitic stratovolcano is also present.

It was at first assumed that activity ended during the Pleistocene, but late eruptions occurred until 2,300 years ago; the latest is dated to 320 BCE.

The Chilean Geological Service monitors the volcano as it is a hazard to Putre, but eruptions could also impact local roads and areas as far east as Bolivia.

[12] The process generates fluids that are ultimately responsible for the evolution of subduction-associated magmas when they interact with the mantle wedge above the downgoing plate.

[18] The area of the volcano is subject to contractional tectonics,[19] with a major thrust fault passing close by,[20] but their relationship to Taapaca's volcanism is not clear.

The volcano has generated an apron of block-and-ash flow deposits especially on the western, southwestern and eastern flanks, which has filled valleys.

Moraines have been described as either poorly[27] or well-developed with six separate stages, of which the lowest lies at 4,250 metres (13,940 ft) elevation on the western slopes.

[28] It is the origin of the Lluta River[25] which has its headwaters on the mountain[29] and subsequently flows through a north-south trending valley west of the volcano.

[2] Taapaca is mostly formed by potassium-rich dacite, although andesite was erupted early during its activity,[31] and one occurrence of rhyolite is reported.

[32] Visible minerals found in rocks erupted at Taapaca include amphibole,[16] apatite,[32] biotite,[33] clinopyroxene, orthopyroxene,[16] hornblende,[34] magnetite and hematite, plagioclase,[32] quartz,[33] sanidine[16] which forms characteristic large crystals,[34] and titanite.

[47] On the southern side of Taapaca, vegetation consists mostly of Puna shrub and steppe, which becomes shrubland farther west.

[50] Fauna encountered in the region includes birds, flamingos, guanacos, huemuls, rheas, vicuñas and viscachas,[46] along with pumas and rodents, which are fairly common.

[16] Eruptions at Taapaca have consisted of lava dome-forming eruptions and explosive activity with avalanches of blocks and ash,[7] which form when lava domes collapse, as has been observed in historical time at the Soufriere Hills and Unzen volcanoes,[52] although these events were much smaller than reconstructed episodes at Taapaca.

[54] The second and probably also the third stage were subject to glacial erosion, which together with later sector collapses resulted in the removal of much of Taapaca's edifice and the exposure of the core of the volcano.

[31] The fourth stage spans the Pleistocene and Holocene and commenced with the emplacement of the Churilinco debris avalanche, which covers a surface of 1 square kilometre (0.39 sq mi).

[31] The Tajane unit was emplaced between 430,000–25,000 years ago on the south-southwestern slopes, covering an area of 30 square kilometres (12 sq mi).

[55] This collapse was triggered by the development of a cryptodome inside the volcano,[52] and Putre is constructed on the avalanche deposit as well as on Tajane, Socapave and Holocene pyroclastic flows.

[23] A pyroclastic eruption occurred, filling in gaps in the Socapave debris avalanche deposit and emplacing more material atop the southern fan of the Tajane unit.

[26] The danger is accentuated by the fact that Holocene activity has affected mainly the southwestern flank, where Putre is located.

[62] Future activity at Taapaca could result in further sector collapses when magma is injected into the edifice and deforms it, to the point that the volcano becomes unstable.

[22] Eruptions between April and November (when the volcano is covered by snow) might generate lahars, as could rainfall during the wet season between December and March; the latter type of lahar happens frequently on present-day Taapaca owing to the steep slopes of the volcano, although it usually results solely in road damage.

[1] It also publishes a hazard map for Taapaca, which shows risk areas for lava bomb falls, pyroclastic flows and tephra fallout.

The figurine was encountered within an outline made of rocks; further Inkan ruins were discovered 200 metres (660 ft) away from the summit on the northwest ridge.

[63] The figurine was probably emplaced to obtain a supply of water, since the Inkans believed that mountains controlled weather and thus the fertility of animals and plants.