Ojos Del Salado - Volcanic Activity

Volcanic Activity

There is no doubt that Ojos del Salado is a recently active volcano, but the question of whether it should be considered currently (or "historically") active is arguable. According to the Smithsonian Institution's Global Volcanism Program, the most recent known eruption was around 1300 years ago, with large error bars. However, there is also some evidence for a minor ash emission in 1993, which would definitely qualify the volcano as historically active. The presence of fumaroles high on the mountain and recent-looking lava flows, albeit of uncertain age, also argues in favor of a categorization as "active." By these definitions Ojos del Salado is the highest historically active volcano on earth. If the older date is accepted, the title of "highest historically active volcano" might reside instead with the somewhat lower Llullaillaco volcano, which certainly has erupted in historic times (most recently in 1877) and should still be considered active. Definitions of "active" being themselves controversial and somewhat arbitrary, the point is mainly of trivial interest.