‘Base surge’ cause of death in Taal's past eruptions —PHIVOLCS

Monitoring of Taal Volcano continues following Sunday's eruption, and among the hazards that could occur is a phenomenon known as the base surge, Philippine Institute of Volcanology and Seismology (PHIVOLCS) director Renato Solidum Jr. said.

Interviewed on "State of the Nation with Jessica Soho," Solidum said based on Taal Vocano's activities, continuous eruptions are likely to happen.

He said base surge, which was the cause of death of many during the volcano's 1754, 1911 and 1965 eruptions, is also a major hazard and would be the "worst case scenario" if it happens.

According to the United States Geological Survey, base surge is a "ring-shaped cloud of gas and suspended solid debris that moves radially outward at high velocity from the base of a vertical eruption column."

"Baka magpakita pa ng kakaibang eruption na imbis na mag-itsa ng bato vertically, baka mag-itsa ito horizontally and baka umabot 'to across the lake at 'yon ang iniiwasan na nakamatay noong 1911, 1754 at 1965," he said.

"Imbes na i-itsa lang pataas ay puwede pang gumapang ang abo at bato ng more than 60 kilometers per hour ang speed na tatawid, lalagpas ng lawa at aabot sa mga barangay, kahit 'yong wall na papunta sa Tagaytay," he said.

In 1754, Solidum said the towns of Taal, Lipa and Tanauan were forced to relocate due to the massive destruction caused by the eruption of Taal Volcano.

In 1911, he said the base surge reached the whole island, including the lakeshore, which led to the death of many.

Meanwhile in 1965, Solidum said the volcano deposits crossed over to the town of Agoncillo.

Alert Level 4 remained raised over Taal Volcano, which means hazardous eruption is imminent.

Alert Level 1 has been raised over Taal Volcano since March last year due to volcanic earthquakes and an advisory on heightened unrest was also released last December, Solidum said.

Solidum, nevertheless, said PHIVOLCS was not surprised by the possible activities of Taal Volcano.

"'Di naman tayo nabigla mismo sa posibleng mangyari sa Taal Volcano," he said. —Ma. Angelica Garcia/LDF, GMA News