BackgroundRecent eruptions were phreatomagmatic and produced surges whose deposits can be found around the active crater. Holocene lava flows cover the northernmost ridge of the volcano.
An older glaciated dacite flow from the northwest side of the volcano has been dated at at 96,000 years. Lavas from Isluga overlie rocks from a dissected volcano (Quimsachatas) to the north and northeast, which erupted 566,000 years ago.
(From: Wörner et al (2000), "Geochronology (40Ar/39Ar, K-Ar and He-exposure ages) of Cenozoic magmatic rocks from Northern Chile (18-22°S): implications for magmatism and tectonic evolution of the central Andes", Rev. geol. Chile vol.27 n.2
Eruptions of Isluga volcano
Major eruptions occurred in 1868, 1869, 1877, and 1878, and smaller eruptions in 1863, 1885 and 1913. The activity reported in 1960 is uncertain.
See also: Sentinel hub | Landsat 8 | NASA FIRMS