MANILA, Philippines – State volcanologists warned on Friday afternoon, October 7, that they have seen increased activity at Bulusan Volcano in Sorsogon.
The Philippine Institute of Volcanology and Seismology (Phivolcs) observed the following:
- Volcanic earthquakes: 29 recorded since 5 am, Thursday, October 6
- Ground deformation: “short-term inflation” or swelling of the volcano’s southern edifice since April
- Sulfur dioxide (SO2) emission: 297 tons per day on September 29
- White steam-laden plumes: weak to moderate emission at the crater and very weak emission at the northwest vents
“The increased seismic activity and short-term ground deformation are likely caused by shallow hydrothermal processes beneath the edifice,” Phivolcs said.
“Since hydrothermal processes are underway beneath the volcano, there are increased chances of steam-driven or phreatic eruptions from its active vents.”
Bulusan has been under Alert Level 0, the lowest level, since August 21. But Phivolcs said the volcano may be raised back to Alert Level 1 if the current activity persists.
Phivolcs on Friday reminded the public not to enter the 4-kilometer-radius permanent danger zone around Bulusan Volcano.
It also advised “people living within valleys and along river or stream channels” to watch out for lahar during heavy rain.
Ash from any phreatic eruption would be hazardous to aircraft, too.
Also on Friday, Phivolcs raised Mayon Volcano in Albay to Alert Level 2 due to “increasing unrest.” – Rappler.com