LEGAZPI CITY, Philippines – Although it was not a very strong explosion, the ash spewed by Mt. Bulusan on Friday reached as far as 25 kilometers across Sorsogon, the Philippine Institute of Volcanology and Seismology (Phivolcs) said yesterday.
The event produced a 200-meter high gray ash plume that was initially seen to drift northwest, but was later confirmed to have drifted to the north and northeast of the volcano.
Volcanologists said winds brought by southwest monsoon carried the ash to areas that could not be reach by the volcanic materials under normal weather condition.
It was Bulusan’s seventh phreatic explosion since it started showing abnormal activity in May.
Volcanologist Celso Mancilla, who is based at the Phivolcs monitoring station in Sorsogon City, said the ashfalls were observed as far as Barangay Inlagadian in Casiguran; Tigkiw, Tugawe, Nazareno, Bugtong and Rizal in Gubat, and Fabrica, San Isidro, Sta. Cruz and San Ramon in Barcelona, all in Sorsogon.
Bulusan is 19 and 25 kilometers away from Barcelona and Gubat, respectively.
“With the magnitude of Bulusan’s latest eruption, it is impossible that ashes would be shot up as far as Barcelona and Gubat. It is the southwest monsoon wind that brought them there,” Mancilla told The STAR.
Helma Canon, a volcanologist based in Legazpi City, said residents must take precautionary measures against ashfalls.
Canon said Friday’s eruption was weaker compared to the previous ones, but it was by far the longest at 11 minutes.
Phivolcs recorded at least four volcanic earthquakes after the 1 p.m. eruption and rumblings were heard six kilometers away from the volcano.
It said it is going to determine if the ash that the volcano spewed last Friday contain lava fragments, which could signal a stronger eruption in the coming days.
Read more on The Philippine Star