One of the world’s deadliest volcanoes has been dormant since the last eruption in 1985, but rising seismic activity suggests it could wake up in the “coming days”.
Colombia’s Nevado del Ruiz recorded 6,000 earthquakes per day last week, prompting officials to raise the alert to the second highest scale and evacuate more than 2,500 families in the area.
According to the Geological Survey of Colombia (CGS), about 57,000 people live in the volcano’s danger zone, which is scattered across parts of six provinces.
And the volcanic eruption in 1985 claimed the lives of more than 25 thousand people, and this is the fourth most dangerous volcanic eruption in the history of mankind, as a result of which people were buried under avalanches from debris of earth and rocks.
CGS believes last week’s quakes are caused by magma moving along a fault system, setting the stage for what could be Nevado del Ruiz’s next deadly eruption.
Nevado del Ruiz is located on the border between the departments of Tolima and Caldas in Colombia.
The volcano, which formed about 150,000 years ago, has a height of 17,717 feet and is located 80 miles west of the capital Bogota. It is a stratovolcano, consisting of several layers of lava, alternating rocks and solidified volcanic ash.
On November 13, 1985, Nevado del Ruiz blasted hot ash and lava into the atmosphere to a height of 23,000 feet, according to Earth magazine.
This event caused a ground rumble that sent debris flows over 98 feet high throughout the area.
The volcanic eruption was small, but the heat released during the event, enveloping the glaciers on the volcano, brought deadly mudflows to the villages below.
Now that Nevado del Ruiz is showing signs of activity, officials have not provided an opportunity to evacuate people nearby.
Emergency officials said livestock, important to many as a way of life in the countryside, could also be moved, or farmers could return during the day to care for them.
However, some residents said they had no plans to leave their homes.
“It doesn’t scare me, because it has already exploded. What gets eaten gets eaten,” said Evalio Ortiz, a potato farmer who survived the 1985 eruption with his wife and five children.
Authorities have said the children must be evacuated even if adult family members decide to stay.
Prior to last week’s activity, officials said there were an average of 50 tremors per day, with few occurrences in the past 10 years.
CGS reported that increased seismic activity was first noted last month, from 6,500 earthquakes on March 28 to 11,000 earthquakes on March 29.
Activity began to slow down on Sunday, but on the same day, the volcano erupted a 3,000-foot ash plume.
Last week, the government raised the eruption alert level from yellow to orange in preparation for an eruption in the coming days or weeks.
“We support the decision of local committees to evacuate some people. It is possible that we will need to evacuate more people in the coming days,” said Luis Fernando Velasco, acting director of the National Disaster Management Unit, after meeting with national and local authorities late Monday evening.
Source: Daily Mail