Courtesy from Blas Sánchez/CNE
The 5.5-degree earthquake that shook Capellades Alvarado de Cartago last November accelerated the landslide that keeps 75 telecommunications towers in check in Irazú volcano.
More than 90% of this equipment is in zones of risk due to the cracks in the top of the massif.
This factor, along with the accumulated rainfall during 2016, was highlighted by the National Emergency Commission (CNE) as responsible for quickening the pace of the anomaly detected in November 2014.
The area surrounding the landslide is about 6 thousand square meters. However, as the problem was detected years ago, some communication towers owners decided to move their equipment to safe areas.
According to a report from the National Seismological Network (RSN), the seismic sequence lasted until December 6th of last year. In addition, the epicenter was located in between the Irazu and Turrialba volcanoes.
Irazú volcano has been in compression, so we do not rule out the occurrence of earthquakes as demonstrated by the replicas. Turrialba Volcano, on the other hand, has been decompressed, which may facilitate the rise of fluids due to open fractures created by the volcano’s recent activity, although it may be speculative, due to the complexity of the volcanic system in Turrialba,”
cites a report published by The National Seismological Network (RSN).
It is important to emphasize that to May of 2015 the landslidw had a length of 80 meters, which is a similar height to the central building of the National Bank located in San José. At this point, that failure would exceed 200 meters.
According to an analysis of the Universidad de Costa Rica (UCR) presented in August, the slide is moving towards Sucio River, which rises in the top of the volcano and is one of the main tributaries of the Sarapiquí River.