INCREASED volcanic earthquakes and sulfur dioxide emission have been observed at Kanlaon Volcano in Negros Island, the Philippine Institute of Volcanology and Seismology (Phivolcs) said yesterday.
“It’s been producing a lot of low-frequency volcanic earthquakes for the past months,” said Ma. Antonia Bornas, chief of Phivolcs’ Volcano Monitoring and Eruption Prediction Division. She did not give figures.
Kanlaon, which remains under Alert Level 1 (low-level unrest), is the third to show increased activities recently, after Taal Volcano in Batangas and Mayon Volcano in Albay.
On Monday, Phivolcs raised at the alert at Mayon to Level 2 (increasing unrest) due to increased volcanic activity, including rockfall events which were way above the daily average.
Last Sunday, Phivolcs said it observed increased degassing activity at Taal Volcano but Alert Level 1 was retained.
On Kanlaon yesterday, Phivolcs said it has recorded five volcanic quakes from 5 a.m. Monday to 5 a.m yesterday, which is similar to the number covering the previous period.
There were 34 volcanic earthquakes recorded from the volcano from 5 a.m. last Saturday to 5 a.m last Sunday, Phivolcs said.
“But more significantly, there was an increase in the sulfur dioxide emission of Kanlaon to 1,089 tons per day yesterday,” said Bornas.
“Normally, Kanlaon spills out only very minimal (sulfur dioxide), about 50 tons per day. Three hundred tons per day is already high but 1,089 tons per days is already is very significant,” added Bornas.
In a bulletin issued yesterday, Phivolcs said it has monitored a 300-meter plume from the volcano. Also, it said the volcano’s edifice is inflated.
Phivolcs said “sudden steam-driven or phreatic eruptions” is possible.
The agency is discouraging the entry of people inside the four-kilometer permanent danger zone and flying of any aircraft close to the volcano.
The state-run Civil Aviation Authority of the Philippines issued an updated notice to airmen (NOTAM), advising flight operators to avoid flying close to Kanlaon’s summit because of the possibility of sudden and hazardous steam-driven or phreatic eruptions.
For Taal, CAAP said operators are advised to steer clear of the volcano’s summit as airborne ash and ballistic fragments resulting from sudden explosions can pose significant hazards to aircraft from the surface up to 10,000 feet.
On Mayon, CAAP told flight operators to avoid flying near the summit as any sudden eruption can emit ash that may be hazardous to aircraft from the surface up to 10,000 feet.
The Diocese of Legazpi asked the faithful to follow safety protocols concerning Mayon’s activities.
“Phivolcs is reminding the communities near Mayon Volcano that the raising of Alert Level 2 means nobody should go within the 6-km permanent danger zone,” said Legazpi Bishop Joel Baylon. “The raising of the Alert Level means that there is possibility that there will be an eruption of the volcano.”
The Lipa Archdiocesan Social Action Commission (LASAC) said it is ready to assist residents who will be affected by Taal’s increased activity. — With Myla Iglesias and Gerard Naval
