LEGAZPI CITY — Mt. Bulusan emitted ash anew at about 11:08 p.m Tuesday but the emission was weak and small, Dr Ed Laguerta, Philippine Institute of Volcanology and Seismology resident volcanologist, said Wednesday.
Laguerta said the mild explosion was registered at their seismic instrument but was not seen or felt due to the very weak activity.
Aside from this, it was dark and cloudy on Tuesday night.
However, in this condition of the volcano, he said, one can expect a series of phreatic explosions.
The veteran volcanologist said that since Bulusan’s first display of abnormality on May 1, the Phivolcs has already registered eight explosions.
On May 1, the agency posted one explosion, two on May 6, and five this June (16, 19, 21 and Tuesday night).
Laguerta said the strong explosions occurred on Mayo 6 and June 19, with the last one spewing 1.5-kilometer-high ash column.
He said the lahar flow along the river channels of the volcano on Tuesday, particularly in Barangay Cogon in Irosin town, is just small as a result of overflowing of the river.
“The mudflow was contained within the river channel,” the Phivolcs official said.
Laguerta explained that the lahar flow on Tuesday was just caused by rains brought about by thunderstorms that lasted for only two hours.
If there would be heavy and sustained rains in the Bulusan area, he said, these would carry down not only the new ash deposits but also those deposited along the slopes during the previous explosions.
The scientist stressed the need for an aerial survey over the volcano, which did not push through on Tuesday, to determine the amount of materials deposited at its summit, adding that heavy lahar flows would be very damaging to the villagers and communities around the Bulusan volcano.