Mount Kanlaon, classified by Phivolcs as an active stratovolcano. | Photo from Mt. Kanlaon Natural Park Facebook page
CEBU CITY, Philippines – The Philippine Institute of Volcanology and Seismology (Phivolcs) raised Alert Level 1 in Mount Kanlaon on Wednesday, March 11, 2020, after it recorded multiple volcanic activities.
“Alert Level 1 status now currently prevails over Kanlaon Volcano, which means that it is at an abnormal condition and has entered a period of unrest,” Phivolcs stated on their volcano bulletin issued 10 a.m. Wednesday.
As a result, Phivolcs advised local governments near Mount Kanlaon to bar anyone from entering a 4-kilometer radius Permanent Danger Zone (PDZ) as means to prevent eventualities that may arise due to the possibilities of ‘sudden and hazardous steam-driven or phreatic eruptions’.
“Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ejecta from any sudden phreatic eruption can be hazardous to aircraft,” they added.
Mount Kanlaon is classified as an active stratovolcano, and usually served to mark the boundary between the provinces of Negros Oriental and Negros Occidental.
Towns and cities located near the volcano are Canlaon City, Guihulngan City, and Vallehermoso town in Negros Oriental, and the towns of Moises Padilla, Isabela, La Castellana, Murcia, Don Salvador Benedicto, and the cities of La Carlota and Bago in Negros Occidental.
The volcano is situated 188 kilometers north of Dumaguete City, the largest city in Negros Oriental, and 92 kilometers south of Bacolod City, the largest city in Negros Occidental.
Unrest
State seismologists said they recorded 80 volcanic earthquakes linked to Mount Kanlaon since March 9, 2020. They added that several of the parameters they placed around the area indicated unrest due to the presence of volcanic activities.
“Volcanic processes are underway deep beneath the edifice that may be caused by deep-seated degassing or hydrothermal activity or magmatic intrusion,” Phivolcs said.
“(The unrest is) dominated by seventy-seven (77) low-frequency events that are associated with magmatic fluids beneath the edifice. The increased seismic activity could be succeeded by steam-driven or phreatic eruptions at the summit crater, despite the absence of visible degassing or steaming from the active vent this year,” they added.
Phivolcs assured the public that it is closely monitoring the volcano.
The last time there was volcanic activity in Kanlaon was in 2016. Ashfall covered several parts of Negros Occidental but there were no casualties. /bmjo