Alert level for Bulusan Volcano up to Level 11

By Ronron
May 20, 2007

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) raised on Sunday the alert level for Bulusan Volcano located in the province of Sorsogon due to more earthquake activities recorded during the past few days.

PHIVOLCS Director Renato Solidum said Alert Level II for Bulusan Volcano is up effective 12 noon yesterday due to the increasing its increasing seismic activity the past three days.

According to Solidum, 674 volcanic earthquakes have been recorded by PHIVOLCS around Bulusan in the past three days.

And from 6am of Saturday until 6am of Sunday alone, Solidum said 223 volcanic earthquakes were recorded.

“We raised the alert level from Alert Level 1 to Alert Level 2 to show to the people that Bulusan Volcano has been more active compared to previous weeks,” Solidum said in Filipino.

According to the PHIVOLCS website, a volcano on Alert Level 1 only manifests low level of seismic, fumarolic and other unrest, which is caused by magmatic, tectonic or hydrothermal disturbance. No eruption is imminent during said level.

Level II, on the other hand, means a volcano shows moderate level of seismic and other unrest with positive evidence for involvement of magma. At this level, there is probable magma intrusion that could eventually lead to an eruption, the PHIVOLCS website said.

Solidum said that at Alert Level II, the danger zone around the volcano is still four kilometers, but the local government should begin planning for their corresponding action and must be prepared to implement it.

Asked if a major explosion could happen in the next few days with the increasing seismic activity of Bulusan, Solidum said: “We don’t have any timetable whether or not there will be a major explosion. What we could foresee are possible ash explosions.”

“But if the volcanic earthquakes continue to happen more frequently, it really means more danger,” he warned.

Among the possible areas that may be affected by an explosion of Bulusan are the towns of Irosin, Juban, Casiguran, Bulan, Barcelona and Gubat, all in Sorsogon, said Solidum.

The last time time PHIVOLCS placed Bulusan at Alert Level II was in May 2006, Solidum said. It was subsequently lowered to Level 1 about two months later, or in July that year.

Solidum said that since Bulusan became active in March 2006, 23 ash explosions occurred, the last of which was only last May 12th./DMS