Plumes of smoke and ash are rising from Colombia’s Nevado del Ruiz volcano. People living on its slopes said they heard “strong, strange noises” coming from the summit of the 5,346 meter (17,535 feet) high mountain on Friday, Saturday and Sunday. Officials said they would extend the orange alert, the second highest, for areas near the summit, which they had first declared almost three weeks ago. More than 25,000 people died in a mudslide (Lahars) caused by Nevado del Ruiz in its last eruption in 1985. Officials have distributed 30,000 face masks to residents living in areas affected by ash from the volcano. The airport in the nearby town of Manizales, in central Colombia, has been closed since the end of May, and will remain so until the volcano ceases to emit ash, officials said. The Volcanic Observatory in Manizales said the plume of ash and gas had risen to a height of 2,000 meters (6,560 feet) on Sunday. Scientists at the observatory warned there was a risk of an eruption “within days or weeks.”
After the November 13, 1985 calamity; officials from the government of Colombia and reporters from newspaper, radio, and television arrived in the morning. Rescue crews were sent to the scene but were unable to reach those trapped in mudflows up to 40 meters (131 feet) thick. Twenty three thousand people died that night in Armero, and in villages nearby. Three quarters of the people living in the Armero were swept away or drowned in the few minutes it took for the swiftly moving mud to cover the town.
Lahars are debris flows and/or mud flows produced by loose soil and rock flowing down the sides of a volcano. The name comes from the Indonesian term where lahars are common volcanic hazards. Pictured below, Nevado del Ruiz and the Lahars flow scars.
The November 13, 1985 eruption took place during night. Although Armero was 74 kms (46 miles) from the crater of Nevado del Ruiz, it took the lahar only two and a half hours to reach the village. A warning did not reach the people in time. The tremendous death toll inspired a new respect for volcanic sites around the world where fire and ice meet in a deadly combination. (Credits: NOAA National Geophysical Data Center and the USGS).
The Master of Disaster
June 18, 2012 – COLOMBIA - Plumes of smoke and ash are continuing to rise from Colombia’s Nevado del Ruiz volcano. People living on its slopes said they had heard “strong, strange noises” coming from the summit of the 5,346m-high mountain on Friday and Saturday. Officials say an orange alert first declared three weeks ago is still in place for areas near the summit. More than 25,000 people died in a mudslide caused by Nevado del Ruiz in its last eruption in 1985. Officials have distributed 30,000 face masks to residents living in areas affected by ash from the volcano. The airport in the nearby town of Manizales, in central Colombia, has been closed since the end of May, and will remain so until the volcano ceases to emit ash, officials said. The Volcanic Observatory in Manizales said the plume of ash and gas had risen to a height of 2,000m (6,500ft) on Sunday. Scientists at the observatory warned there was a risk of an eruption “within days or weeks.” -BBC
June 8, 2012 – The Nevado Del Ruiz Volcano Heats Up in Colombia: Local authorities ordered the evacuation of 24 families residing near the Nevado Del Ruiz volcano (17,457 feet or 5,321 meters). The volcano, located in central Colombia, is being evacuated due to concerns that there could be an eruption in the coming days or weeks. The order will be in place for one month. A further 39 families have been notified of a potential evacuation. Some of the people who would suffer the greatest risk in the event of an eruption have failed to respond to the evacuation order, according to the newspaper El Espectador. The evacuated families will each be given a compensation of 150,000 pesos ($84.68 USD) from the Municipal Office for the Prevention of Natural Disasters (OMPAD), according to Radio Santa Fe. According to the most recent report from the Seismological and Volcanic Observatory of Manizales, the volcanic instability is likely to continue over the next few weeks. The alert level for Nevado Del Ruiz sits at orange, meaning an eruption is probable but not imminent.
Pictured above, a cluster of rounded boulders was deposited on a river terrace by a lahar in the Río Chinchina valley, 59 kilometers (37 miles) WNW of the summit of Colombia’s Nevado Del Ruiz volcano on November 13, 1985. The boulders were carried as bedload and deposited against the tree, which served as an obstruction to flow. Note the mudline on the tree that marks the upper flow surface of the lahar. The man next to the boulder gives one an idea of the huge lahars (mudflows) involved. Photo by Tom Pierson, 1985 (U.S. Geological Survey).
Nevado Del Ruiz is a broad, glacier-covered volcano in central Colombia that covers more than 200 square kilometers (124 sq. Miles). Pictured below is a hazards map for the volcano, with the dark red showing mudflows (lahars) from the deadly November 13, 1985 eruptions.
The concern is that the volcano is capable tremendous destruction. On November 13, 1985; Nevado Del Ruiz erupted causing Colombia’s worst natural disaster – killing 23,080 and injuring 10,000. It was South America’s most deadly volcanic eruption. The top picture is a photograph of that tremendous eruption. Although it was only a VEI 3 event, the mudflows and lahars took their deadly toll. (Credits: Hazards map from Wright and Pierson, Narrative – RSOE Emergency and Disaster Information Service (EDIS), W. G. Foster and The Smithsonian National Museum of Natural History).