It is a relatively small peak, within the collapse scarp of a debris avalanche from earlier in the Holocene, which was built up by eruptions to fill much of that feature. There are two craters at the summit, with the one to the south displaying fumaroles. In 1995 its first eruption in recorded history occurred in the form of a phreatic eruption.[1]
^Ludovico Bertonio, Kastilla-Aymara simi qullqa: Iru. - Ichu espinoso.Phutunqu. - Un vasito de barro o redoma.PhutunquvelPhujru. - Hoyo de la tierra sin agua, no muy hondo.