Phivolcs says Mayon eruption will last at least 2 to 3 months
Published Feb 5, 2018 01:58 pm
By Niño Luces
LEGAZPI CITY, Albay -- The Philippine Institute of Volcanology and Seismology (Phivolcs) today said the eruption of Mayon Volcano will last at least two to three months.
Mayon Volcano spews ash and lava. (File Photo/ Czar Dancel / MANILA BULLETIN)
Ed Laguerta, Phivolcs resident volcanologist based in Legazpi City, described two scenarios that Mayon will either continue to ooze lava with small eruption in between or Mayon will have its major blast or pyroclastic flow, a deadly combination of hot lava blocks, pumice, ash and volcanic gas that may glide down the slope that could devastate residential areas in the villages surrounding the volcano.
Laguerta said that at present, Mayon is exhibiting scenario one, which is the continued lava eruption that may last until three months, but the probability of scenario 2, or the progression into explosive eruption, has the lower probability.
According to Laguerta, Phivolcs is still considering the volume of eruptible magma with an approximate 50 million cubic meters based on estimate of eruptible magma from magma supply rate per year.
“Scenario 1, Mayon will continue its lava fountaining and quite extrusion of lava flow into the Miisi gully and Bonga gullies. The present activities could be similar to 1993 eruption. The current conditions with no measurable indication of changes as of the present and Mayon will be maintained to alert level 4. While scenario 2, if lava degasses sufficiently to plug the vent and overpressurize the volcanic conduit or magma ascent rates drastically increase this and an explosive eruption could become imminent; scenario 2 is similar to the 2000 to 2001, 1984 and 1968 eruption; Lava flow phase followed by explosive eruption phase, and from this, alert level 5 will be raised,” Laguerta explained.
When asked by the Manila Bulletin how many percent Mayon will have its scenario 2, but Laguerta refuse to give a rough estimate. “Mahirap sabihin kung ilang porsyento. Mag-aassume kayo nyan. But the higher probability is scenario 1, which is happening now. Eto lang ang problema, baka tumagal ito kasi pakonti-konti inilalabas ni Mayon yung magma,” he said.
Laguerta explained that based from historical accounts, Mayon eruption lasted for at least two to three months or even at least four months.
“Babalikan namin yung ugali ng Mayon, kung ano ang ugali ng Mayon ganun din ang mangyayari, may shortest may long. So we assume the long period kasi safety pa rin yung pinag-uusapan dyan. Two to three months ang pinakamatagal ng Mayon. Pero may maiksi naman, kaya nga ang sana, matapos na ito ng maaga,” he said.
Laguerta noted that if scenario 1 will continue, that lead to longer eruption.
“Kung pakonti-konti ang inilalabas ni Mayon, yung lang, matagal tayo dito. Matagal tayong magsasama-sama nito,” he said.
Meanwhile, according to Dr. Cedric Daep, chief of Albay Public Safety and Emergency Management Office (APSEMO), if Mayon will continue to erupt for at least two to three months, evacuees will stay for longer days.
“Mas napapatagal din yung evacuees. Nung 1984, umabot tayo ng four months sa evacuation center, 1993 umabot tayo ng more than three month. So kahit dito, ibaba ng Phivolcs sa alert level 3, kahit mag-decamp tayo ng eight kilometers, maiiwan pa rin yung seven at six. So matatagalan pa
yun na ibaba sa level 2. So expect na ang duration nito ay matagal pa,” Daep narrated.
Mayon Volcano spews ash and lava. (File Photo/ Czar Dancel / MANILA BULLETIN)
Ed Laguerta, Phivolcs resident volcanologist based in Legazpi City, described two scenarios that Mayon will either continue to ooze lava with small eruption in between or Mayon will have its major blast or pyroclastic flow, a deadly combination of hot lava blocks, pumice, ash and volcanic gas that may glide down the slope that could devastate residential areas in the villages surrounding the volcano.
Laguerta said that at present, Mayon is exhibiting scenario one, which is the continued lava eruption that may last until three months, but the probability of scenario 2, or the progression into explosive eruption, has the lower probability.
According to Laguerta, Phivolcs is still considering the volume of eruptible magma with an approximate 50 million cubic meters based on estimate of eruptible magma from magma supply rate per year.
“Scenario 1, Mayon will continue its lava fountaining and quite extrusion of lava flow into the Miisi gully and Bonga gullies. The present activities could be similar to 1993 eruption. The current conditions with no measurable indication of changes as of the present and Mayon will be maintained to alert level 4. While scenario 2, if lava degasses sufficiently to plug the vent and overpressurize the volcanic conduit or magma ascent rates drastically increase this and an explosive eruption could become imminent; scenario 2 is similar to the 2000 to 2001, 1984 and 1968 eruption; Lava flow phase followed by explosive eruption phase, and from this, alert level 5 will be raised,” Laguerta explained.
When asked by the Manila Bulletin how many percent Mayon will have its scenario 2, but Laguerta refuse to give a rough estimate. “Mahirap sabihin kung ilang porsyento. Mag-aassume kayo nyan. But the higher probability is scenario 1, which is happening now. Eto lang ang problema, baka tumagal ito kasi pakonti-konti inilalabas ni Mayon yung magma,” he said.
Laguerta explained that based from historical accounts, Mayon eruption lasted for at least two to three months or even at least four months.
“Babalikan namin yung ugali ng Mayon, kung ano ang ugali ng Mayon ganun din ang mangyayari, may shortest may long. So we assume the long period kasi safety pa rin yung pinag-uusapan dyan. Two to three months ang pinakamatagal ng Mayon. Pero may maiksi naman, kaya nga ang sana, matapos na ito ng maaga,” he said.
Laguerta noted that if scenario 1 will continue, that lead to longer eruption.
“Kung pakonti-konti ang inilalabas ni Mayon, yung lang, matagal tayo dito. Matagal tayong magsasama-sama nito,” he said.
Meanwhile, according to Dr. Cedric Daep, chief of Albay Public Safety and Emergency Management Office (APSEMO), if Mayon will continue to erupt for at least two to three months, evacuees will stay for longer days.
“Mas napapatagal din yung evacuees. Nung 1984, umabot tayo ng four months sa evacuation center, 1993 umabot tayo ng more than three month. So kahit dito, ibaba ng Phivolcs sa alert level 3, kahit mag-decamp tayo ng eight kilometers, maiiwan pa rin yung seven at six. So matatagalan pa
yun na ibaba sa level 2. So expect na ang duration nito ay matagal pa,” Daep narrated.