Viedma (volcano)

Viedma ([ˈbjeðma]) is a subglacial volcano located below the ice of the Southern Patagonian Ice Field, an area disputed between Argentina and Chile. The 1988 eruption deposited ash and pumice on the ice field and produced a mudflow that reached Viedma Lake. The edifice of the volcano is mainly composed out of basalt or older silica poor basement rocks, while ejecta have SiO₂ contents between 62 and 66%. Numerous ash layers in the Viedma lake indicate numerous past eruptions.

Map of Viedma, Santa Cruz Province, Argentina