Worst case scenario in Taal's activity is prolonged eruption —PHIVOLCS

Prolonged eruption would be the worst-case scenario for Taal Volcano's intense unrest, according to the Philippine Institute of Volcanology and Seismology (PHIVOLCS) on Monday.

"Kung titingnan po natin ang historical eruptions ng Taal, puwede po 'yang kasing-ikli ng three days katulad ng 1911 eruption which occured 'yung main magmatic phase January 27 to January 30 of 1911 o puwede 'yang tumagal ng pitong buwan like the 1754 eruption," Mariton Bornas, chief of Volcano Monitoring & Eruption Prediction Division of the PHIVOLCS, said in a press conference.

"It could be short, it could be long. Hopefully, short lang kasi malaking dagok po 'yan sa mga kababayan natin sa Batangas," she added.

Volcanic tsunami is also among the possible hazards of Taal's activity.

"Kapag pumuputok po nang malakas, explosive eruption, may studies na ginawa diyan eh, either driven by explosion or may ground deformation o pag-alsa ng lupa na sumisipa sa tubig," Bornas said.

Fissuring, landslides, ground liquefaction are also possible.

Generation of lahar is likely in the portion of Laurel, Batangas.

"Medyo mas malalaki ang mga ilog diyan eh. Sa ibang parte ng bulkan, masyado matarik ang dalisdis so mahirap mag-accumulate ng deposits. Pero dito sa side ng Laurel mayroong plain diyan eh at may malaking drainage ng mga ilog, so puwede kang mag-generate ng mga lahar diyan," Bornas said.

Alert Level 4 is currently raised over Taal Volcano, meaning hazardous eruption is possible within hours to days.

Alert Level 1 has been raised over the volcano since March 2019 and an advisory on heightened unrest was also released last December, according to Bornas.

The PHIVOLCS official, nevertheless, admitted that experts were quite surprised by the pace of Taal's activity.

"Ang ikinagulat lang namin ay 'yung bilis ng escalation. Masyado pong mabilis for Taal. Mas mabilis pa po siya sa 1911 escalation," she said.

She underscored that the speed of the volcanic activity's progression, however, will not determine the final magnitude of its eruption.

Bornas said that a hazardous eruption from Taal would look like an atomic bomb explosion.

"Siguro ang closest na puwede ihalintulad sa malakas na pagputok ng Taal ay atomic bomb explosion —'yung istura niya, hindi 'yung energy," she said.

"Mayroon kang matayog na eruption column tapos mayroong ring na kumakalat mula doon sa base ng eruption column. Itong ring na ito, ito 'yung base surge, tumatawid siya ng lawa at tinatamaan niya ang mga pamayanan sa paligid ng lawa. 'Yung base surge po talaga ang primary hazard," she added.

Very fine particles from volcanic ash would take about three days before they settle from the atmosphere, Bornas said. —KG, GMA News