Event description


On November 13, 1985, a relatively small phreatic-magmatic eruption of Nevado del Ruiz in the Central Andes of Colombia caused a catastrophic event due to the existence of a 21 km2 ice cap covering the volcano. The quick erosion and mobilization of unstable ice bodies as well as the surface melting of snow and ice triggered several lahars, the most important of which destroyed the city of Armero. More than 23`000 people were killed. About 90 Mio m3 of water was discharged. Estimated peak discharge ranged up to 48`000 m3/s. (The damage costs were estimated at 200 Mio US$.)




23`000 people killed or missing, 4`420 injured, 5`092 homes destroyed, and 210`000 hectares of land stripped or buried in muddy debris. (The damage costs were estimated at 200 Mio US$.)


Data source


Pierson, T. C., Janda, R. J., Thouret, J. J., Borrero, C. A. (1989): Perturbation and melting of snow and ice by the 13 November 1985 eruption of Nevado del Ruiz, Colombia, and consequent mobilization, flow and deposition of lahars. Journal of Volcanology and Geothermal Research, 41, 17 - 66.