Mayon showing increased earthquake activity – Phivolcs
MANILA, Philippines — State seismologists have been observing an increase in volcanic earthquakes in Mayon since Monday.
The latest bulletin from the Philippine Institute of Volcanology and Seismology (Phivolcs) stated, “Since 3:47 PM (PST) yesterday (03 July 2023), the Mayon Volcano Network began recording a continuous tremor-like series of weak volcanic earthquakes that steadied and increased in strength this morning and persists to the present.”
“This resulted in an abrupt and sustained increase in the level of seismic energy release beginning 03 July 2023,” Phivolcs said on Tuesday.
The agency added that volcanic earthquakes last approximately 11 seconds and recur at intervals of five seconds.
It also observed a dome collapse and pyroclastic density currents (PDCs) from the summit.
Phivolcs also reported rockfall activities continue with PDCs flowing for approximately two minutes down the Basud gully (eastern slopes), Mi-isi gully (southern slope) and Bonga gully (southeastern slope) within a distance of one to two kilometers from the crater.
A cloud of ash fall was also seen.
“Trace ashfall from the PDCs has been reported by residents of the town of Guinobatan and the city of Ligao,” Phivolcs said.
Meanwhile, state volcanologists noted a spike in sulfur dioxide emission to 1,558 tons per day.
This occurrence “is likely driven by magmatic gas activity within the edifice,” said the agency.