Mayon Fires a 1,600-Metre Ash Plume: Strombolian Bursts and 11 Quakes in 24 Hours

Mayon Volcano fired another column of ash on Wednesday morning, November 4. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) said the volcano belched a 1,600-metre plume of ash at 8:22 a.m., which drifted southwest, while Alert Level 3 remains raised over the volcano in Albay province.

This is a new, dated development in a story WorldEye last covered on November 1, when PHIVOLCS raised Mayon to Alert Level 3 after its October 30 eruption and more than 2,000 people left the danger zone. Wednesday's activity shows the eruption is not settling back down: the volcano is producing fresh ash, glowing at the crater and generating earthquakes at an elevated rate.

The agency's 24-hour monitoring report, released on Wednesday, recorded minor Strombolian activity at Mayon — occasional low-level explosions that shoot glowing-hot lava fragments, ash and gas into the air from the summit crater. Alongside the ash plume, observers recorded a crater glow, meaning incandescent material is visible at the summit after dark.

The instruments told the same story. PHIVOLCS counted 11 volcanic earthquakes in the past 24 hours, measured sulfur dioxide emissions of 1,894 tonnes per day, and observed ground deformation described as inflation of the edifice, with short-term deflation on the northeastern sector. A swelling edifice with sustained gas output is the signature of magma still moving beneath the cone, not of an eruption winding down.

Mayon has been under Alert Level 3 since its moderately explosive eruption on Friday, October 30 — an event that lasted nearly six minutes and sent a 3,000-metre column of ash skyward, roughly double Wednesday's plume. Alert Level 3 means the volcano is experiencing a high level of unrest, with an increased likelihood of lava flows and hazardous pyroclastic density currents, PHIVOLCS says.

Because of that, entry into the six-kilometre permanent danger zone around the volcano remains prohibited, due to the danger of pyroclastic density currents, lava flows, rockfalls and lava fountaining. PHIVOLCS also advised aircraft to avoid flying close to the volcano. The 2,462-metre Mayon, a near-perfect cone about 330 kilometres southeast of Manila, is the Philippines' most active volcano.

The numbers to watch are the ones in Wednesday's report. A rising earthquake count, larger or more frequent ash plumes, faster inflation or a jump in sulfur dioxide would each point toward a larger eruption building; a falling trend across several days would be the first real sign of easing. Wednesday's figures — 11 quakes, continued inflation, strong gas output — sit firmly in the 'still restless' column.

Strombolian bursts matter for a second reason: they are visible. Each burst throws incandescent fragments above the crater rim, and on a clear night the crater glow PHIVOLCS recorded is the same glow that volcano watchers around the world follow on webcams.

The six-kilometre zone exists because Mayon's hazards move faster than anyone can outrun, which makes remote watching the only sensible seat. WorldEye's volcano webcams collection gathers live volcano views from around the world in one place, and the earthquake tracker shows the seismic activity that accompanies unrest like Mayon's.

The official word remains PHIVOLCS' daily monitoring reports and bulletins. Until the earthquake count, gas emissions and deformation all turn down together, Wednesday's plume should be read for what it is: an eruption in progress, five days after it began, with no sign yet that it is finished.