According to Phivolcs, the rising of magma materials is evidenced by the high level of gas emission rate of the volcano with the last reading of sulfur dioxide (SO2) indicating a level of 2,656 tons per day.
The baseline figure of Mayon’s SO2 emission during its period of repose is only at 500 tons per day, Phivolcs told The STAR.
Yesterday, Phivolcs also said that volcanologists closely monitoring Mayon Volcano reported six low frequency and six high frequency volcanic earthquakes during the past 24-hour observation period.
During the same observation period, the volcano’s crater was visible but no crater glow was observed and its steaming activity was weak to moderate.
"Alert Level 1 remains raised at Mayon Volcano," Phivolcs said, stressing that Alert Level 1 is meant to call attention to increased volcanic activity specifically an increased likelihood for steam-driven or ash explosion that may occur with little or no warning at all.
As Mayon’s alert level remains at Alert Level 1, Phivolcs maintains its advisory that the public must refrain from entering the six-kilometer radius Permanent Danger Zone (PDZ) around the volcano especially within the southeast sector where volcanic flows, falling and rolling debris may be produced from a possible explosion.
Phivolcs raised the alert level at Mayon Volcano from Alert Level 0 to Alert Level 1 last week, when it showed continuous signs of restiveness after the occurrence of an ash explosion on Oct. 11.