MANILA — The Philippine Institute of Volcanology and Seismology (Phivolcs) on Monday recorded two volcanic quakes from the restive Mayon Volcano in Albay during its 24-hour observation period from 7 a.m. last Sunday to 7 a.m. Monday.
In its latest bulletin, Phivolcs said Mayon spewed moderate to voluminous steam but no crater glow was observed Sunday evening.
The latest measurement of the volcano’s sulfur dioxide showed falling an average of 420 tons per day.
It added that Mayon remains under Alert Level 3, which means the magma is at the crater and hazardous explosive eruption is due within weeks.
Phivolcs warned anew to avoid entering the six-kilometer radius permanent danger zone (PDZ) around the volcano and the seven-kilometer extended danger zone (EDZ) on the southeastern flank are still enforced due to the danger of rock falls, landslides and sudden explosions or dome collapse that may generate hazardous volcanic flows.
Meanwhile, Renato Solidum, Phivolcs director, said there is no sign yet that the alert needs to be raised to Level 4.
Alert Level 4 means a hazardous eruption is possible within days.
He said Alert Level 4 would be hoisted once the magma movement accelerates and volcanic tremors occur more frequently.
On Sunday, Phivolcs spotted a 350-meter lava flow on the eastern side of Mayon’s Bonga gully.
Phivolcs said the slow extrusion of lave from the crater was due to volcanic tremors and rock fall events during the past week.
Solidum clarified the lava flow was “non-explosive” because it was a quiet lava discharge from Mayon’s summit.
Mayon first exhibited high unrest last Sept. 15 after Phivolcs detected 39 rock fall events and 32 volcanic earthquakes that indicated magma disturbance and volcanic gas activity.
More than 12,000 people have been evacuated from the foot of Mayon Volcano.
The Mayon Volcano has erupted nearly 50 times over the last 600 years. The most destructive eruption was in February 1841, when lava flows buried a town and killed 1,200 people.