Sulfur gas and quakes jolts Mayon

LEGAZPI CITY, Dec. 11 -- At least 29 volcanic earthquakes jolted Mayon Volcano on Friday, the highest recorded seismic event this week indicating that the volcano's abnormality is still up, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.

Scientists are continuously observing Mayon volcano's fluctuating seismic precursors such as quakes, gas emission and ground deformation these are indication that the volcano's seismic activity may possibly lead to an explosive eruption.

Phivolcs advisory said high and low frequency harmonic quakes were detected by seismic instruments signifying that magma intrusion is developing in the volcano's crater vent.

Ed Laguerta, Phivolcs resident volcanologist, said the agency seismic networks has recorded a total of 44 earthquakes that rocked the volcano since Dec. 1 this year.

The volcano continue to billow high volume of sulfur dioxide gas with 710 tons emitted for the past 24 hours period indicating a fluctuating trend ranging from 592 tons per day to 1,303 tons per day for the past three days.

While the volcano's steaming activity was still on moderate level.

Laguerta said the fluctuating rates of gas emission are indicative that magma is building up to the crater in preparation for an imminent eruption.

He said the agency is still assessing the abnormal state of the volcano based on given parameters like ground deformation, volcanic quakes and gas emission, and crater glow.

Precise Leveling result indicates a 5.0 mm swelling on the volcano edifice which was noted at the Buang while Lidong lines posted a 4.0 mm inflation.

The volcano did not exhibit crater glow due to heavy clouds prevailing on the crater summit on Thursday evening.

Alert level 2 remains hoisted over Mayon volcano, Phivolcs strongly recommend that the six-km Permanent Danger Zone including the seven-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)