LEGAZPI CITY — The Philippine Institute of Volcanology and Seismology (Phivolcs) on Wednesday reiterated its warning to residents here against being complacent over Mayon’s activity slowdown for the past several days.
Phivolcs chief Renato Solidum, in an interview, said the volcano was still consistently exhibiting eruptive activities to include continuous lava flow and fountaining, pyroclastic flows, earthquakes, increased sulfur dioxide emission and bulging at the edifice.
Solidum said, “so far, the volcano has emitted 70 million cubic meters of lava since it erupted on January 13.”
He stressed that the large volume of lava that was expelled was due to an open vent at the volcano’s crater.
Solidum clarified news reports saying that the volcano’s activity was waning and slowing down. “They are over-interpreting what we are reporting never in our bulletins did we say that the volcano’s activity has been on a downtrend.”
He said aside from the visual observation, another important aspect was the result of the instruments’ measurements recorded inside the volcano.
During the past several days, visual observation has been hampered by heavy clouds that cover the volcano but Phivolcs instruments detected that large volume of lava continuously flowed and recorded earthquakes and tremors signifying that magma is building up and intruding the volcano’s vent.
Solidum noted of two scenarios: first, the volcano as it now continues to exhibit lava fountaining events, ash plumes, lava flow, pyroclastic flows and second, blockade over the volcano or gas pressure and magma buildup that could trigger a big explosion.
“So far the first scenario is prevailing in Mayon’s eruptive state,” he said.
Solidum said all parameters for Alert Level 4 status were still present.
“As long as magma is advancing and flowing at the crater summit and our instruments indicate that the volcano is still on the eruptive stage, Alert Level 4 will remain,” he said.
The volcano might be quiet, but it was possibly gathering energy for another eruptive episode, Solidum explained.
Phivolcs bulletin for the past 24-hour observation period said the volcano exhibited sporadic to near continuous lava fountaining, lava flow and degassing episode that generated a steam-laden ash plume up to 400 meters high.
Lava fountaining was accompanied by rumbling sounds audible within 10 kilometers of the summit crater.
As Alert Level 4 remains in effect, the public is advised not to enter the 8-kilometer extended danger zone. (Mar Serrano/PNA)
