Cerro Napa is a Pliocene

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 per ...

north of the Salar de Coposa, straddling the border between

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 ...

and Chile. The wide volcano rises about above its surrounding terrain and has a partially preserved

summit crater A volcanic crater is an approximately circular depression in the ground caused by volcanic activity. It is typically a bowl-shaped feature containing one or more vents. During volcanic eruptions, molten magma and volcanic gases rise from an unde ...

. Part of its slopes are covered with

pyroclastic Pyroclastic rocks (derived from the el, πῦρ, links=no, meaning fire; and , meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroc ...

s; radiometric dating has yielded ages of 11.9 ± 0.6, 9.99 ± 0.1 and 1.38 million years ago. In the past the volcano was glaciated, with glaciers descending to elevations of . This low elevation probably relates to the easterly position of the volcano and likely correlates to lake highstands in Salar de Coposa,

Salar de Empexa Salar may refer to: Places *Salar, Spain, a municipality in Granada *Salar, Murshidabad, a census town in West Bengal, India **Salar railway station *Salar, Uzbekistan, a town in Tashkent District *Kampong Salar, a village in Mukim Mentiri, Brunei ...

and

Salar de Huasco Salar may refer to: Places *Salar, Spain, a municipality in Granada *Salar, Murshidabad, a census town in West Bengal, India **Salar railway station *Salar, Uzbekistan, a town in Tashkent District *Kampong Salar, a village in Mukim Mentiri, Brunei ...

References

Pleistocene stratovolcanoes Miocene stratovolcanoes Stratovolcanoes of Chile Stratovolcanoes of Bolivia {{Bolivia-geo-stub