LEGAZPI CITY, Dec. 4 --Mt. Mayon's edifice continue to bulge on Friday, an indication that the volcano's condition is still on a restive state that may lead to a possible explosive eruption.
The Philippine Institute of Volcanology and Seismology (Phivolcs) in its recent aerial and ground deformation surveys indicated that the volcano's edifice was still inflated in the two leveling sites of the 2,450 meters high volcano.
Phivolcs Precise Leveling result showed that the volcano remained inflated by 5.0 mm at the Buang leveling lines while Lidong lines posted a 4.0 mm swelling, indicative that magma is still developing.
Dr. Ed Laguerta, Phivolcs resident volcanologist, said that the swelling of Mayon's edifice based on the ground deformation survey would shelve the plan to lower the volcano alert level from 2 to one.
Laguerta said that the recently concluded Precise Leveling measures changes between established benchmark due to volcanic forces acting underneath the volcano.
The study reveals that there are still changes in the vertical and horizontal ground surface strains that are related to magma intrusion, indicative that the volcano is still in the restive stage.
Phivolcs seismic instruments detected on Thursday a significant dropped in the volcano's seismicity, registering only four quakes as compared to the 13 high and low frequency detected on Wednesday.
The volcano for the past 24 hours period disgorged 629 tons of sulfur dioxide (SO2), compared to the 858 tons a day on Wednesday, which is way above the normal level at 500 tons a day.
Mayon exhibited a moderate steaming activity for the past 24 hours observation period while crater glow was not observed Wednesday because of heavy clouds covering the crater summit.
Phivolcs scientist are continuously observing the volcano's fluctuating seismic precursors such as quakes, gas emission and ground deformation .
Alert level 2 is still up over Mayon volcano, Phivolcs strongly recommend that the 6-km Permanent Danger Zone including the 7-km extended danger zones should be off limits to any human activity due to threat from sudden explosions and rockfalls from the upper slopes of the volcano. (PNA)