Mayon’s lava, debris spill over upper slope

LEGAZPI CITY, Philippines — After undergoing  silent eruptions for over a month, Mayon Volcano’s lava flows and other detached and collapsed debris have spilled over the upper slope and are no longer confined in  major gullies, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported yesterday.

Paul Alanis, Phivolcs resident volcanologist at the Lignon Hill Observatory in this city, said the upper gullies are now full, causing lava flows and other dome-collapse debris to roll toward the middle slope.

“But the good news is that these rolling volcanic materials are still converging in major gullies as they reach the middle slopes,” Alanis told The STAR yesterday.

In the past 24 hours, Phivolcs recorded a rise in the volcano’s sulfur dioxide emissions, from 1,758 tons the other day to 2,047 yesterday.

The emissions were accompanied by five low-frequency volcanic quakes, four pyroclastic density currents and 158 rockfall events.

A week ago, Phivolcs estimated that Mayon had already ejected over 7.3 million cubic meters of debris since its alert level was raised to three in June.

The spillover can be seen at night as incandescent materials spread out while rolling down the upper slope facing the Daraga-Legazpi-Sto. Domingo areas.

The spillover of ejected materials from the major gullies poses a threat to communities on the lower slope and beyond the six-kilometer-radius permanent danger zone, Alanis said.

“This is the reason why we recommend banning entry inside the permanent danger zone. We cannot tell when these hazardous volcanic materials can breach the permanent danger zone,” Alanis said.