By Mar S. Arguelles
LEGAZPI CITY --- The rising number of volcanic quakes, tremors, gas and bulging of Mayon Volcano’s edifice are signs that pressure is continuously pushing magma materials towards the volcano summit generating lava fountaining, pyroclastic flows and ejection of high ash clouds, a top official of the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said on Tuesday.
Renato Solidum, Undersecretary of the Department of Science and Technology (DOST and concurrent Phivolcs director, said low-frequency quakes have been observed lately indicating that magma at the volcano’s vent is being pushed producing lava and pyroclastic materials.
Solidum when asked what to expect in the coming days said the overall condition of Mayon is the volcano remains in a restive state where all parameters for an eruptive event are still taking place.
Solidum, in a phone interview said, “what we are closely monitoring is the high and low-frequency tremors beneath the volcano, the gas output and the inflated edifice which are all signs that magma is building up.”
He said the volcano has spewed 25 million cubic meters of molten rocks since it erupted on Jan. 13.
When asked what could be expected in the coming days, Solidum reiterated what he told President Duterte on Monday, that the worst case scenario that could happen include: first is a full-blown eruption causing a big volume of lava to creep and pyroclastic flow.
A second phase is a post-eruption event of a high volume of lahar flows during intense rains which could reach to communities and block road networks.
Phivolcs data indicate that 10.5 million cubic meters of lahar were currently emitted by Mayon volcano eruption.
Phivolcs bulletin for the past 24-hour observation period said a total of 119 volcanic quakes, 9 tremor events were observed on Tuesday.
Sulfur gas emission remained high at 1,916 tons per day while the volcano edifice remained inflated, Phivolcs instrument recorded.
Mayon volcano’s restive state exhibited an energetic lava effusion with sporadic lava fountaining that generated pyroclastic flow or “uson” at around 11:05 PM Monday.
Pyroclastic flows cascaded down the Miisi and Bonga Gullies in the town of Daraga and Legazpi City.
The eruption produced a significant volume of ashfall that covered the towns of Camalig and Guinobatan before 9PM.
Alert Level 4 remains in effect over Mayon Volcano.