Reduced emissions of sulfur dioxide, a major gas component of magma or molten rocks, was observed in Taal Volcano on Wednesday, but state volcanologists warned that the danger of an explosive eruption is still present as quakes persist and a volume of magma has already reached near the volcano’s surface.
Philippine Institute of Volcanology and Seismology (Phivolcs) Volcano Monitoring and Eruption Prediction Division chief Mariton Bornas said that sulfur dioxide emission in Taal Volcano further decreased, measuring at an average of 153 tonnes per day.
Wednesday’s sulfur dioxide level was lower than the 344 tonnes per day measured on Tuesday and the 4,353 tonnes per day recorded on Monday
According to the United States Geological Survey, sulfur dioxide indicates that magma is near the surface and could be a sign that the volcano will erupt soon.
However, Bornas emphasized that a reduced sulfur dioxide level for two straight days does not mean that the public is already safe from Taal’s possible explosive eruption.
“Puwedeng nababarahan lamang ang mga labasan ng SO2 (sulfur dioxide) or puwede ring nag-degas na ‘yung ibabaw ng magma at hindi na makalabas ‘yung SO2. Maraming pwedeng maging factors,” she explained.
Bornas added that they need to study an overall trend if there will be a continuous downfall in the said gas levels for them to evaluate if the activity in Taal is already weak.
According to Bornas, government volcanologists are weighing all parameters, including gas emissions and volcanic quakes, every day to check if it is already acceptable to lower the alert level.
In the agency’s latest monitoring on Taal, Bornas noted that volcanic quakes recorded in the past 24 hours were “significantly weaker” compared to the days after its phreatic or steam-driven eruption on January 12.
From Tuesday morning to Wednesday morning, the Philippine Seismic Network (PSN) plotted six volcanic tremors registered at magnitudes 1.5 to 2.4 with no felt event.
While the Taal Volcano Network, which can record small earthquakes undetectable by the PSN, recorded 481 volcanic temblors including eight low-frequency earthquakes also in the past 24 hours.
As these quakes persist, Phivolcs said that there is still a continuous magmatic intrusion beneath the Taal edifice, which may lead to further eruptive activity. (Alexandria San Juan)
