Steam buildup causes Bulusan ash explosion

ABS-CBN News

Posted at Feb 21 2011 09:56 AM | Updated as of Feb 22 2011 05:48 AM

MANILA, Philippines - Mount Bulusan in Sorsogon province spewed a 2-kilometer ash cloud at 9:15 a.m. Monday, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said.

PHIVOLCS Director Renato Solidum said the ash is drifting in a southwest direction going to Irosin town.

"We expected this. We are on Alert Level 1. At this stage, it is possible to have steam-triggered explosions which are not really very strong. People are still advised not to enter the 4-kilometer permanent danger zone," he told radio dzMM.

Solidum said all aircraft should steer clear away from he volcano since the volcanic ash could clog engines.

He also warned that the ash emission could trigger respiratory illnesses for people living near the volcano.

PHIVOLCS on Sunday recorded 2  volcanic earthquakes near Bulusan during the past 24 hours. It noted "weak steaming activity drifting to the southwest direction" from volcano's northwest thermal vents.

"There was no steaming observed at the crater and other known thermal vents. Results of ground deformation surveys conducted last 25 – 29 January 2011 showed that the volcanic edifice was slightly deflated relative to December 2010 survey," the institute said.