Lava starts flowing out from Mayon volcano’s southeast flank

Mayon Volcano eruption on December 29, 2009. Tryfon Topalidis / Wikipedia photo

MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) spotted lava flow from the southeast side of Mayon Volcano in Albay yesterday, signaling an increased level of unrest towards an imminent eruption within weeks.

According to Phivolcs regional volcanologist Ed Laguerta, lava started to pour 100 meters downward from where the lava dome was located at 5 a.m. yesterday. This indicated a sluggish extrusion of lava from the crater.

He also said that the lava could have surged down slope further than some 350 meters in length compared to the flow observed a week ago from the eastern portion of Bonga Gulley facing Legazpi-Daraga.

“The volume is bigger and the stretch wider compared to the lava which flowed at the right side of the lava dome last Oct. 12,” Laguerta said.

Mayon’s seismic network traced two volcanic earthquakes related to the ascent of degassed magma from the volcano’s previous eruption during the last 24-hour observation period.

“What flowed out was not yet the new magma we are expecting which could trigger the eruption,” Laguerta said, explaining a degassed magma is viscous and creates slow moving lava.

Laguerta also warned that ‘if what came out were fresh magma, the soft eruption which started Sept. 12 can now normally proceed to a full-blown eruption.’

Even with lava oozing from the crater, Phivolcs maintained the current eruption Alert Level 3 for Mayon Volcano.  Alert level 5 is raised in an actual eruption while zero is equivalent to no activity.

“We have to maintain the present Alert Level 3 to prepare for sudden changes in parameters as the volcano gathers enough pressure underneath towards an eruption,” Laguerta said.

Aside from the lava flow, the faint crater glow is also intensifying but it cannot be fully observed now due to recent storms.

Moderate volcanic emission has been tainted from whitish to brownish steam plumes that drifted west and northwest due to the presence of ash at a shallow source.

According to Phivolcs, the 269 tons low discharge of sulfur dioxide could be due to sealed gas pores at the feature from the viscous magma.

Phivolcs volcanologists warned barangays Matanag, Mabinit, Buyuan and Bonga, towns within the seven-kilometer extended danger zone whose residents have not yet evacuated, could be initially hit by lava pouring out from the volcano once the explosion occurs. They are also threatened with rock falls, landslides, dome collapse and abrupt explosions.

With report from Cyra Moraleda