A study reconstructs an extreme geological episode in Tenerife to assess its current impact
The Institute Geosciences Barcelona of the CSIC (GEO3BCN-CSIC), in collaboration with the Autonomous University of Barcelona and the University Clermont Auvergne, has rebuilt the last great geological event cascade that took place on the Canary Island of Tenerife 180,000 years ago: the eruption of The coat, and you have evaluated what would happen if it happened today.
Extreme geological events are natural phenomena (volcanic eruptions, earthquakes, landslides or tsunamis) of low probability but with a high impact, which represent a risk for today’s society due to their difficulty in making predictions about their occurrence.
These episodes, which can cause chain effects and have consequences on a local and global scale, are potentially probable on volcanic islands such as the Canary archipelago.
Geological chain events are potentially probable on volcanic islands such as those of the Canary archipelago.
The results of the work, published in the journal Journal of Geophysical Research: Solid Earth show that the main urban centers and possible evacuation routes in Tenerife would be affected, since they would be covered by the deposits of the pyroclastic flows and probably by the fall of ash.
In addition, the seismicity accumulated in the center of Tenerife during a collapse event of the volcanic building, as occurred 180 thousand years ago, would produce “catastrophic” effects in various parts of the island and trigger a “devastating” landslide in the Icod Valley.
This slippage, in turn, would produce a tsunami which would have a severe impact not only on the north and west coasts of Tenerife but also on other coasts of the Canary archipelago.
Reaching the conditions for an eruption like El Abrigo can take thousands to hundreds of thousands of years.
Marta López-Saavedra (GEO3BCN)
“At present, the volcanic system of Tenerife is not in a situation similar to that of the last caldera eruption. In fact, reaching the conditions for an eruption like that of El Abrigo can take thousands to hundreds of thousands of years ”, he emphasizes. Marta Lopez Saavedra, main author of the article. “At the current stage, the Teide and Pico Viejo volcanoes still seem too young to reach these conditions,” he adds.
According to López Saavedra, “the chances of an eruption such as El Abrigo occurring today are very low, but zero risk does not exist and, unfortunately, eruptions cannot yet be predicted.”
Investigate to prevent
“The results obtained during our study replicate the most catastrophic scenario that can occur in Tenerife, which makes it possible to establish a range of situations and design a risk management protocol without exceeding minor events, or falling short in the event of events of greater impact. ”, Explains the researcher.
López Saavedra considers that this analysis will contribute to “improve the current Canary Islands Volcanic Emergency Management Plan (Singer), detailing the appropriate danger scenarios and optimizing prevention actions long before any such emergency occurs ”.
The researcher highlights the importance of implementing improvements in disaster reduction policies by the agencies responsible for emergency management. “This implies more information and training for the population of the Canary Islands,” he stresses.
To carry out this analysis, modeling software has been combined with Geographic Information Systems to simulate each event separately.
Technological advance: key to Geosciences research
To carry out this analysis have been combined modeling software with Geographic Information Systems to simulate each event separately and, later, analyze the global result of all the scenarios obtained.
The research team used the software VORIS 2.0.1. to obtain the area potentially affected by the pyroclastic streams; a plugin for QGIS 2.14 that allows to calculate the impact of a possible earthquake; the software SLIDE of Rocscience Inc. to analyze the slope stability under seismic conditions; and finally, the software VolcFlow to simulate the propagation in space and time of the possible tsunami, as a consequence of the collision of the landslide against the ocean.
López-Saavedra et al. “Cascading Effects of Extreme Geohazards on Tenerife (Canary Islands)”. Journal of Geophysical Research: Solid Earth.
Rights: Creative Commons.