HE The Colombian Geological Service (SGC) reported that seismic activity has increased again in the last 24 hours in the area where Nevado del Ruiz volcano is located, Therefore, its instability and the risk of a large-scale explosion remain.
This is with an additional component as explained to EL TIEMPO John Macario Londoño, head coach of SGC GeothreatsHe noted that now seismic activity is concentrated near the crater.
“The current state of the volcano is still very unstable. The seismicity has changed its dynamics. This is in the sense that although earthquakes continue to be recorded in different regions around the crater, lThe main feature we observed is that it is already concentrated in the crater.Londono explained.
This is because magma is now closer to the volcano’s mouth. and also interacts with magma in the same region since 2015. According to the expert, this fluid accumulation has different effects:
“This seismicity is different from the others because it is the result of the activity of fluids that are both ascending into the atmosphere and present inside the volcano. That means more outgassing, more ash and thermal anomalies going on at the bottom of the crater.”
Concerning the perception of some segments of the population, who insisted that the threat was lessened given the absence of a major eruption for days, Londoño drew attention to what was happening in Nevado del Ruiz. “Normalize”
“The activity occurring is not normal. The activity under these conditions may fluctuate. There will be days when the threat decreases or increases. This is exactly part of the range of abnormal behavior and instability. This is worrying. So we are talking about the possibility of an explosion within days or weeks, because the situation is unpredictable, it can appear in a day or two, at 10 or 20, and even calm down. Even in other parts there have been cases of volcanoes that apparently calmed down and suddenly erupted into a massive eruption.”Londono explains.
The Geological Service expert explained that while it is not possible to predict how a major eruption in Nevado del Ruiz will occur, it is possible to predict how such an event will occur due to its nature and background.
“Nevado del Ruiz is slightly different from the volcanoes in Hawaii in that the type of volcano is called a shield volcano and is characterized by the eruption of lava.l Ruiz is a stratovolcano whose eruptions are often explosive because of the composition and arrangement of rock and magma.”
As such, this type of eruption and El Ruiz have historically had huge columns of gas and ash, often rising into the atmosphere. If they get too large, they tend to collapse. creating pyroclastic flows (mixture of hot volcanic gases, hot solid materials and trapped air)Londoño is dangerous when traveling at high speeds in excess of 100 kilometers per hour and in very hot (more than 400 degrees Celsius). This material, combined with water from rivers coming out of the volcano and melting snow-covered glacier, can cause mudflows.
“What can be expected is a massive eruption, characterized by a massive eruption similar to that experienced in 1989, when ash fell on various towns, including Manizales, and some mudflows formed,” says the SGC expert. An event like 1985 could occur, we hope. It doesn’t happen like that.”
ENVIRONMENTAL ARTICLE
Source: Exame
