LEGAZPI CITY, Philippines — Mayon Volcano has a crack in its crater at the southeast sector from where pyroclastic density currents (PDCs) flow downwards as Alert Level 4 stays.
“The crack was due to continuous lava flows,” Ed Laguerta, resident volcanologist of the Philippine Institute of Volcanology and Seismology (Phivolcs) based at Ligñon Hill Observatory, said yesterday.
PDCs, called uson by locals, flowed from the crack and were confined within the farthest recorded reaches of 4.6 kilometers at the Miisi, 5.2 kilometers at Bonga and 4.2 kilometers at the Basud gullies.
The old lava dome that was a remnant of the volcano’s eruption in 2014 was pulverized by strong eruptions after Jan. 13 but continuous lava flows gave the volcano a “facelift” at its crater.
He said a team of scientists is now conducting a survey to assess the critical parameters of the volcano such as inflation, sulfur gas emission and volcanic quakes to assess its present eruption status.
He also labeled the eight-kilometer extended danger zone around the 2,462-meter volcano “cautious” after Science and Technology Undersecretary and Phivolcs director Renato Solidum warned last Friday that PDCs from a possible strong eruption could reach five kilometers and beyond.
“We will come up with a new assessment this week after a new survey will be completed today or tomorrow, which will be our basis to maintain or lower the present Alert Level 4,” Laguerta said.
He said the present physical aspect of the volcano is quiet but the instruments showed an abnormality inside.
“The lower slope of Mayon already recorded a plateau in the graph of our monitoring instruments. This means that the supply of magma is no longer ascending to the upper chamber or the pressure is not massive anymore,” Laguerta told The STAR.
But Mayon’s middle slope remained inflated or bulging, which means magma is still present inside the upper chamber of the volcano, he added.
Meanwhile, no decampment will be ordered among evacuees unless Phivolcs would lower Mayon’s alert level, said Cedric Daep, chief of the Albay Public Safety and Emergency Management Office (APSEMO).
At least 17,329 families or 66,009 persons remain in 61 evacuation centers, APSEMO reported.
APSEMO estimated that with a budget of P200 daily per family for the evacuees, the government spends at least P3.5 million a day or P346.5 million for a 100-day prolonged evacuation scenario.
President Duterte does not want to receive reports of food shortage in evacuation centers, Claudio Yucot, Bicol director of the Office of Civil Defense, told media at a briefing yesterday in Camp General Simeon Ola.
As this developed, Department of Social Welfare and Development Bicol assistant regional director for operations Arwin Razo said the government had already spent P275 million for food and non-food items for the evacuees.
“We are ready for the 100-day scenario,” Razo said, adding that “mechanized relief operations are running round-the-clock.”
Mayon has been acting up for more than a month now.
A total of 56 lava fountaining episodes were recorded at Mayon in the past 24 hours, Phivolcs said yesterday.
The agency also said the sulfur dioxide emitted by Mayon hit 2,148 tons per day last Monday, higher than the normal volume of 500 tons per day.
A total of 72 volcanic earthquakes were also detected by Mayon’s seismic monitoring network.
The volcano started spewing steam and ash last Jan. 14. It was placed under Alert Level 4 last Jan. 22 after it spewed a giant ash column. – Cet Dematera, Helen Flores
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