Nevado Anallajsi is a

stratovolcano 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 ...

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

. The date of its last eruption is unknown, but its youngest lava flows appear to have erupted from a vent on the north flank of the mountain. The main composition of the volcano is

andesitic Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...

and dacitic. It overlies a plateau which is composed of

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 ...

. The volcano covers an area of and is 10.2 mya old based on its erosion state, while other estimates indicate an age of 2.6 mya.

References

Sources

* Stratovolcanoes of Bolivia Subduction volcanoes Polygenetic volcanoes Volcanoes of La Paz Department (Bolivia) Five-thousanders of the Andes Pleistocene stratovolcanoes {{LaPazBO-geo-stub

See also

References

Sources