The Philippine Institute of Volcanology and Seismology (Phivolcs) raised Mayon Volcano to Alert Level 1 after renewed earthquake activity.
1 Nov 17 – Phivolcs resident volcanologist Ed Laguerta said the agency is closely monitoring the surge in volcanic earthquakes.
Monitoring instruments recorded 32 quakes on Saturday, 12 on Sunday, and 13 on Monday, said Laguerta.
However, despite the “abnormal condition”there was no imminent “magmatic eruption,” he assured. “So far, there is still no indication that Mayon’s abnormal behavior has intensified.”
Laguerta added the parameters for an abnormal state of a volcano include: gas quakes (volcanic, harmonic) gas emission, edifice inflation, magma intrusion, and crater glow.
Nonetheless, Phivolcs advised the public to refrain from entering the 6-kilometer Permanent Danger Zone (PDZ).
Mayon Volcano’s last erupted in September 2014.
Thanks to Laurel for these links