Mayon Volcano had two short-lived lava bursts early evening on Friday and shortly after midnight on Saturday, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported.
The first lava burst occurred at 6:36 p.m. on Friday, while the other one was recorded at 12:06 a.m. on Saturday, Phivolcs said.
Volcanologists said the lava bursts were accompanied by tremors and rumbling sounds on the ground.
“Short-lived lava bursts accompanied by seismic and infrasound signals also occurred,” a Phivolcs morning bulletin said.
The agency also recorded 31 volcanic earthquakes including 23 tremor events lasting from one minute to 52 minutes.
Phivolcs also recorded one lava flow or “pyroclastic density current (PDC)” and 87 rockfalls at Mayon Volcano. Debris from these events were deposited within four kilometers of the crater.
“The lava flows have maintained their advances to approximately 3.4 kilometers in Bonga (southeastern), 2.8 kilometers in Mi-isi (south), and 1.1 kilometers in Basud (eastern) Gullies,” Phivolcs said.
Meanwhile, an average of 592 tons of sulfur dioxide discharge was recorded on October 20.
Moderate plumes rising up to 1,000 meters tall were also seen on Friday. The plumes drifted south-southwest and west, PHIVOLCS reported
The bulletin said Alert Level 3 remains in effect at Mayon Volcano as it continues to show intensified unrest or magmatic unrest.
The state volcanology agency reiterated that entry into the six-kilometer radius Permanent Danger Zone is prohibited. Aircraft are not allowed to fly close to the volcano.
It added the volcano poses hazards such as rockfalls, landslides or avalanches, ballistic fragments, lava flows and lava fountaining, PDCs; moderate-sized explosions as well as lahar during heavy and prolonged rainfall.