El Chichon eruption - April 1982, Mexico

The moderate scale eruption of El Chichon lasted from 28 March to 4 April 1982 generating pyroclastic surges and flows that dammed adjacent drainages including the Magdalena River¹,². This created a 4 km long and 40 km wide lake that drained catastrophically and inundated the town of Ostuacan with a mixture of hot water and pyroclastic sediment. The hot water was contained at Penitas Hydroelectric Dam where one casualty and 3 injuries took place².

The eruption was unique due to the release of unusually large amounts of sulphur into the atmosphere. Three weeks after the eruption, the volcanic aerosol had circled the Earth and severely affected aircraft particularly in the northern hemisphere. The cost of window damage caused by the gases for one company, Japan Airlines is estimated at 6.8 million US dollars¹.

Pyroclastic flows and surges destroyed nine villages south of the volcano while damaging lahars were also triggered due to heavy rain falling on unconsolidated pyroclastic deposits².

¹ Bernard, A & Rose, W.I. 1990. The Injection of Sulphuric Acid Aerosols in the Stratosphere by the El Chichon Volcano and its Related Hazards to the International Air Traffic. Natural Hazards. Vol. 3, pp 59-67

² Macias, J.L, Capra, L, Scott, K.M, Espindola, J.M, Garcia-Palomo, A & Costa, J.E. 2004. The 26 May 1982 breakout flows derived from failure of a volcanic dam at El Chichon, Chiapas, Mexico. GSA Bulletin. Vol. 116, pp 233-246