Mayon spews 4 PDCs Friday night, monitored for increased activity
Four dome-collapse pyroclastic density currents from Mayon Volcano's summit lava dome have been recorded on Friday early evening, the Philippine Institute of Volcanology and Seismology has said.
In a volcano advisory at 8 p.m., PHIVOLCS said the four PDCs were observed since 6:09 p.m. and flowed for four minutes down the Basud Gully over a distance of three to four kilometers.
‘Closely monitored’
PHIVOLCS said Alert Level 3 is still up over Mayon Volcano, but "a change in the dispersal and runout of PDCs is being closely monitored."
"It is strongly recommended that the areas inside the six-kilometer-radius Permanent Danger Zone remain evacuated and that communities within the seven- and eight-kilometer radius be prepared in case current PDC activity worsens," PHIVOLCS said.
"Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from eruptions can be hazardous to aircraft," it added.
PHIVOLCS said it was closely monitoring Mayon Volcano and that any new development would be communicated to all stakeholders.
Ashfall, SO2
PHIVOLCS said the Friday night PDCs were preceded by a longer, four-minute-long PDC on the Basud Gully at 1:01 PM. Its observation was hampered by cloud cover.
It added ashfall from the PDCs had been reported by residents of Tabaco City and recorded by the Mayon Resthouse IP camera.
"Satellite monitors detected a pronounced increase in SO2 emission yesterday, while SO2 emission measured by campaign survey today averaged 1,002 tonnes/day," PHIVOLCS said.
"The increase in volcanic gas flux is only slightly above background and still below the typical ranges of eruption gas flux from Mayon," it added.
PHIVOLCS said in its 8 p.m. bulletin that the Mayon Volcano Network had recorded 48 weak low-frequency volcanic earthquakes since 5:00 a.m. on Friday but seismic energy release has been sustained at generally the same level since June 15, 2023.
Ashfall, SO2
PHIVOLCS said the Friday night PDCs were preceded by a longer, four-minute-long PDC on the Basud Gully at 1:01 PM. Its observation was hampered by cloud cover.
It added ashfall from the PDCs had been reported by residents of Tabaco City and recorded by the Mayon Resthouse IP camera.
"Satellite monitors detected a pronounced increase in SO2 emission yesterday, while SO2 emission measured by campaign survey today averaged 1,002 tonnes/day," PHIVOLCS said.
"The increase in volcanic gas flux is only slightly above background and still below the typical ranges of eruption gas flux from Mayon," it added.
PHIVOLCS said in its 8 p.m. bulletin that the Mayon Volcano Network had recorded 48 weak low-frequency volcanic earthquakes since 5:00 a.m. on Friday but seismic energy release has been sustained at generally the same level since 15 June 2023.
Alert Level 3
According to PHIVOLC's monitoring, Alert Level 3 means a high level of unrest.
Under this alert level, there are sustained increases in the levels of volcanic earthquakes, some may be perceptible. There is an occurrence of low-frequency earthquakes, volcanic tremors, and rumbling sounds.
Also expected are forceful and voluminous steam/ash ejections, sustained increases in SO2 emission rates, and ground deformation/swelling of the edifice.
Activity at the summit may involve dome growth and/or lava flow, resulting in rockfall.
The interpretation is magma is near or at the surface, and activity could lead to hazardous eruptions in weeks.
Danger zones may be expanded up to eight kilometers from the active crater.
Gov’t ready —Marcos
President Ferdinand "Bongbong" Marcos in early June said the Philippine government was ready to assist affected residents if the situation of the Mayon and Taal volcanoes worsen.
In a chance interview, Marcos said the government was constantly monitoring the situation of the two volcanos.
"We watch it very, very closely. Make sure that any of the communities that could be affected are evacuated and are given assistance while they are evacuated until the time that they can return to their homes," Marcos told reporters. —NB, GMA Integrated News