Phivolcs raises Alert Level 1 on Kanlaon Volcano
Published Mar 11, 2020 12:00 am
By Alexandria Dennise San Juan
The Philippine Institute of Volcanology and Seismology (Phivolcs) raised on Wednesday the alert status of Kanlaon Volcano from Alert Level 0 to Alert Level 1 after an increase in seismic activity was observed in the past days.
Photo shows the crater of the Mt. Kanlaon in Negros Oriental viewed from the town of Moalboal in Cebu (Juan Carlo de Vela / MANILA BULLETIN FILE PHOTO)
In the latest update of Phivolcs issued Wednesday morning, Alert Level 1 status now prevails over Kanlaon, which means the volcano is at an "abnormal condition" and has "entered a period of unrest."
State volcanologists observed a rise in the seismic activity of Kanlaon since March 9 when the volcano’s seismic monitoring network recorded a total of 80 volcanic earthquakes dominated by 77 low-frequency events associated with "magmatic fluids beneath the edifice."
According to Phivolcs, the increased volcanic tremors in Kanlaon could be followed by steam-driven or phreatic eruptions at the summit crater, despite the absence of visible degassing or steaming from the active vent this year.
"Ground deformation data from continuous GPS measurements indicate a period of long-term slow inflation of the edifice since 2017, while short-term electronic tilt monitoring on the southeastern flanks recorded slow inflation of the lower slopes since May 2019 and pronounced inflation of the upper slopes in the end of January 2020," the agency explained in its advisory.
The bureau pointed out that these parameters indicate that volcanic processes are "underway deep beneath the edifice" which may be caused by "deep-seated degassing or hydrothermal activity or magmatic intrusion."
Following the raising of Kanlaon's danger level, Phivolcs reminded local government units and the public that entry into the four-kilometer radius Permanent Danger Zone must be "strictly prohibited" due to possibilities of sudden and hazardous phreatic eruptions.
Phivolcs said civil aviation authorities should advise pilots to avoid flying close to the volcano's summit as ejecta from any sudden phreatic eruption can be hazardous to aircraft.
Apart from Kanlaon, the state volcanology agency is also closely monitoring other active volcanos in the country including Taal and Mayon which are currently at Alert Level 2 or at a "moderate level of unrest."
Photo shows the crater of the Mt. Kanlaon in Negros Oriental viewed from the town of Moalboal in Cebu (Juan Carlo de Vela / MANILA BULLETIN FILE PHOTO)
In the latest update of Phivolcs issued Wednesday morning, Alert Level 1 status now prevails over Kanlaon, which means the volcano is at an "abnormal condition" and has "entered a period of unrest."
State volcanologists observed a rise in the seismic activity of Kanlaon since March 9 when the volcano’s seismic monitoring network recorded a total of 80 volcanic earthquakes dominated by 77 low-frequency events associated with "magmatic fluids beneath the edifice."
According to Phivolcs, the increased volcanic tremors in Kanlaon could be followed by steam-driven or phreatic eruptions at the summit crater, despite the absence of visible degassing or steaming from the active vent this year.
"Ground deformation data from continuous GPS measurements indicate a period of long-term slow inflation of the edifice since 2017, while short-term electronic tilt monitoring on the southeastern flanks recorded slow inflation of the lower slopes since May 2019 and pronounced inflation of the upper slopes in the end of January 2020," the agency explained in its advisory.
The bureau pointed out that these parameters indicate that volcanic processes are "underway deep beneath the edifice" which may be caused by "deep-seated degassing or hydrothermal activity or magmatic intrusion."
Following the raising of Kanlaon's danger level, Phivolcs reminded local government units and the public that entry into the four-kilometer radius Permanent Danger Zone must be "strictly prohibited" due to possibilities of sudden and hazardous phreatic eruptions.
Phivolcs said civil aviation authorities should advise pilots to avoid flying close to the volcano's summit as ejecta from any sudden phreatic eruption can be hazardous to aircraft.
Apart from Kanlaon, the state volcanology agency is also closely monitoring other active volcanos in the country including Taal and Mayon which are currently at Alert Level 2 or at a "moderate level of unrest."