Nevado del Ruiz Volcano, Colombia - increased activity

AI Thread Summary
Thermal anomalies at Arenas Crater of Nevado del Ruiz have been low-to-moderate since October 2022, but seismic activity surged significantly starting March 24, 2023. A record number of earthquakes occurred, with 11,600 recorded on March 30, marking the highest daily count since monitoring began in 1985. The seismic events, primarily rock-fracturing earthquakes, were concentrated 2-5 km southwest of the crater at depths of 2-4 km. The Alert Level was raised to Orange on March 30 due to the increased seismicity and associated fluid movement signals, which also indicated ash emissions, with a plume reaching 1.8 km above the summit. Historical context highlights the volcano's destructive potential, as its last significant eruption in 1985 resulted in 23,000 fatalities. Residents are advised to stay alert and prepare for possible evacuation.
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https://volcano.si.edu/volcano.cfm?vn=351020

Servicio Geológico Colombiano’s (SGC) reported that thermal anomalies, persistent in Arenas Crater at Nevado del Ruiz since October 2022, were low-to-moderate in intensity. Seismicity increased significantly on 24 March, characterized by rock-fracturing earthquakes mainly located 2-5 km SW of Arenas crater at depths of 2-4 km. On 28 March there were 6,500 of these events, the highest daily count since 2010. The number of daily events continued to increase and on 29 March the seismic network recorded 11,000 earthquakes, the highest daily count since seismic monitoring began in 1985; on 30 March there were 11,600 earthquakes. The maximum magnitudes per day were also increasing, with a M 2.6 on 24 March, a M 2.7 on 29 March, and a M 3.1 on 30 March. The earthquake locations migrated towards Arenas Crater, though the depths remained within the same range. The Alert Level was raised to Orange, Level II (the second highest level on a four-level scale) on 30 March. In addition to the swarm, seismic signals indicating fluid movement continued to be recorded and some were associated with ash emissions; the tallest plume on 30 March rose 1.8 km above the summit and drifted NW and SW.

The Street reported, "The last time the Nevado del Ruiz volcano was active, it erupted and killed 23,000 people in Colombia, wiping out the town of Armero in the process."

Pay attention to volcanoes in the neighborhood and be prepared to evacuate.Eight days ago, about April 3.

As of April 9

 
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