The alert status of Mayon has passed from level 0 (normal) to 1 (abnormal conditions).
The Phivolcs decision follows a change of the measured parameters:
- SO2 emissions have increased from 500 to 1000 tons / day some days since July, and then declined.
- The GPS network and tilt meters show an inflationary trend.
- After a seismic swarm between 3 and 6 August, likely associated with fracturing of rock, a volcano-tectonic earthquake was registered on 9 September.
- Fourteen wells located on the southeast side saw decrease the discharge of water, and one dried up, phenomenon due to magma movement beneath the building, according to Ed Lagerta, volcanologist.
Crater vapor emissions remain moderate and no glow was observed last night.
The permanent danger zone remains at 6km. Because of avalanche hazards, phreatic eruptions can occur without warning signs.
- The Manila Times