No slowing down for Mayon – Phivolcs
Published Feb 9, 2018 12:08 am
By Ellalyn De Vera-Ruiz
CRISIS MANAGER — Secretary Francis N. Tolentino, presidential adviser on political affairs and Mayon Volcano Crisis manager, visits a kitchen facility for Mayon evacuees in Ligao City, Albay. He is joined by Ligao Mayor Patricia Gonzalez-Alsua.
Mayon Volcano has ejected lava fountains at least 35 times over the past 24 hours with one lasting almost four hours, the Philippine Institute of Volcanology and Seismology (Phivolcs) said yesterday.
Since Wednesday noon, Mayon had 35 lava fountaining events. Phivolcs said discrete episodes lasted nine to 233 minutes and were accompanied by rumbling sounds audible beyond 10 kilometers of the volcano summit.
Also observed were incandescent lava fountains 150 meters high, which generated steam-laden plumes that rose 800 meters from the summit before drifting northeast.
Throughout Wednesday evening, lava flows and consequent incandescent rockfalls were observed in the Miisi and Bonga-Buyuan river channels.
Volumes of incandescent lava flows have advanced to 3.3 kilometers, 4.5 kilometers and 400 meters down the Miisi, Bonga and Basud gullies, respectively.
Pyroclastic flow — a fast-moving current of hot gas and volcanic matter — were deposited 4.6, 4.4 and 4.2 kilometers down the Miisi, Bonga and Basud gullies, respectively.
Phivolcs recorded 36 volcanic earthquakes from Wednesday until yesterday morning most of which corresponded to lava fountains.
Sulfur dioxide emission, on the other hand further increased to 2,525 tons per day since Wednesday. Sulfur dioxide emission tends to increase through time as magma degasses with increasing rates as it moves up from great depths beneath the volcano, Phivolcs explained.
Gathering energy
Phivolcs chief Renato Solidum said, “so far, the volcano has emitted 70 million cubic meters of lava since it erupted on January 13.”
The large volume of lava expelled, he said was due to an open vent at the volcano’s crater.
Solidum clarified reports 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.”
Solidum noted 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 are 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. (With reports from Carizza Ibañez and PNA)
CRISIS MANAGER — Secretary Francis N. Tolentino, presidential adviser on political affairs and Mayon Volcano Crisis manager, visits a kitchen facility for Mayon evacuees in Ligao City, Albay. He is joined by Ligao Mayor Patricia Gonzalez-Alsua.
Mayon Volcano has ejected lava fountains at least 35 times over the past 24 hours with one lasting almost four hours, the Philippine Institute of Volcanology and Seismology (Phivolcs) said yesterday.
Since Wednesday noon, Mayon had 35 lava fountaining events. Phivolcs said discrete episodes lasted nine to 233 minutes and were accompanied by rumbling sounds audible beyond 10 kilometers of the volcano summit.
Also observed were incandescent lava fountains 150 meters high, which generated steam-laden plumes that rose 800 meters from the summit before drifting northeast.
Throughout Wednesday evening, lava flows and consequent incandescent rockfalls were observed in the Miisi and Bonga-Buyuan river channels.
Volumes of incandescent lava flows have advanced to 3.3 kilometers, 4.5 kilometers and 400 meters down the Miisi, Bonga and Basud gullies, respectively.
Pyroclastic flow — a fast-moving current of hot gas and volcanic matter — were deposited 4.6, 4.4 and 4.2 kilometers down the Miisi, Bonga and Basud gullies, respectively.
Phivolcs recorded 36 volcanic earthquakes from Wednesday until yesterday morning most of which corresponded to lava fountains.
Sulfur dioxide emission, on the other hand further increased to 2,525 tons per day since Wednesday. Sulfur dioxide emission tends to increase through time as magma degasses with increasing rates as it moves up from great depths beneath the volcano, Phivolcs explained.
Gathering energy
Phivolcs chief Renato Solidum said, “so far, the volcano has emitted 70 million cubic meters of lava since it erupted on January 13.”
The large volume of lava expelled, he said was due to an open vent at the volcano’s crater.
Solidum clarified reports 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.”
Solidum noted 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 are 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. (With reports from Carizza Ibañez and PNA)