Nevado Del Ruiz

Nevado Del Ruiz

The eruption
1. 3:06pm - Pumice fragments and ash thrown from the sides of the vent
2. 7:00pm - The Red Cross order an evacuation but shortly after the evacuation called, ash stopped falling and the evacuation was called off
3. 9:08pm - Eruption began as lava started to erupt from the summit crater. Explosion accompanied by heavy rainfall. Approximately 20 million cubic metres of hot ash and rocks were thrown into the air across snow-covered glacier. Materials were transported across the snow by pyroclastic flows and fast-moving, hot, turbulent clouds of gas and ash. Hot flows caused rapid melting of the snow and ice, creating large volumes of water. Water pick up debris and formed hot lahars as much as 40m thick and travelling 50km/h
4. 11:28pm - Lahars reached Armero and in a few minutes the town was swept away or buried, killing 1927 people
Nevado Del Ruiz
1. Strato-volcano in the Andes
2. Highest Columbian volcano with history of violent activity
3. Produced by subduction of oceanic Nazca Plate beneath South American Plate
4. Known as the 'sleeping lion'. Dormant for nearly 150 years until 1985
Primary effects on the people and landscape
1. Hot clouds of ash and gas (nuées ardentes)
2. Magma thrown into the air from the vent
3. Avalanches of hot ash, pumice and rock fragments (pyroclastic flows)
Secondary effects on the people and landscape
1. Mud up to 40m deep was deposited in the valleys in the path of the lahars
2. 5,000 homes destroyed
3. 23,000 killed
4. 5,000 injured
5. Temperature of the lahars served as fertile breeding ground fo fungi and bacteria. Survivors with minor cuts were killed by infections
6. Roads blocked making it hard for rescue workers to rescue survivors from deep mud
7. Cost Colombia $7.7 billion. 20% of country's GDP at the time

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	Created by Olivia Brooklyn over 10 years ago