El Chichon, Mexico 1982
El Chichon was another volcano in which residents had little warning of impending danger. El Chichon was believed to be an extinct volcano since it had been more than 600 years since it’s last eruption. Throughout 1980 and 1981 there were a number of earthquakes in the area. Geologists created hazard maps which highlighted the risks to the region but there was no increase in monitoring activity for the volcano. Then in 1982, the volcano had two large eruptions over the course of a week (March 28th and April 4th).
On March 28th at 11:30pm the volcano had its first eruption a plume that reached 27km and had a diameter of 100km. Hot volcanic material rained down around the volcano, setting the landscape on fire. This eruption only lasted two to three hours, after which things settled down with only smaller steam eruptions. Those living near the volcano quickly evacuated after the first eruption and more continued to do so over the next several days. However, some after seeing the limited activity over several days returned home.
Then on April 4th the volcano erupted again with a force much greater than that of the March 28th eruption. A pyroclastic flow spread out 8km from the volcano and destroyed the village of Francisco Leon where as many as 1,000 people perished. The flow produced deposits that were 100 meters wide and three meters thick causing substantial devastation. Two Plinian eruptions following the pyroclastic flow and created plumes that spanned at least 29 km. Nine villages were completely destroyed and as many as 2,000 people were killed.
More than 24,000 square kilometers were completely covered with ash. Over $55 million (equivalent to $132 million in today’s dollars) of damage was done to crops and cattle ranchers had to move their cattle as most of the pastureland was covered in ash. It remains as the largest volcanic disaster in modern Mexican history.