LEGAZPI CITY – Mt. Mayon's abnormal activity has waned, prompting the Philippine Institute of Volcanology and Seismology (Phivolcs) to downgrade its status to Alert Level 1, signifying low level of unrest, from Level 2, moderate level of unrest.
In its Thursday bulletin, Phivolcs said the alert status of Mayon in Albay province was downgraded due to the continued decline in its monitored parameters.
The Phivolcs bulletin said since the start of the year, Mayon Volcano has exhibited a steady decline in its monitored parameters.
The lowering of the alert status of Mayon means the likelihood of an eruption occurring within the immediate future has weakened.
Also, volcanic earthquake activity has declined to a daily average of zero to one. Volcanic earthquake is typically attributed to rock fracturing beneath the edifice and occasional rockfall.
The sulfur gas (SO2) output measured at 312 tonnes per day is likewise considerably below the background level of 500 tonnes per day.
Crater glow associated with superheated gas escaping the summit vent has been faint and only visible through the aid of a telescope.
"The observation of stable summit conditions are consistent with the absence of magma re-supply to the shallow levels of the edifice," the bulletin said.
However, the public is still reminded to avoid entry into the 6-kilometer Permanent Danger Zone (PDZ) due to the perennial hazard of rockfall, avalanche, ash puff, and sudden steam-driven or phreatic eruption at the summit area.
“Furthermore, people living in valleys and active river channels are cautioned to remain vigilant against sediment-laden stream flows and lahars in the event of prolonged and heavy rainfall brought about by the advent of the rainy season," Phivolcs added. (PNA)