THE Philippine Institute of Volcanology and Seismology (Phivolcs) said on Tuesday that there was no more trace of sulfur dioxide from Taal Volcano in the past 24 hours.

"Sulfur dioxide emission was below instrumental detection," said Phivolcs in its 8 a.m. bulletin.

Sulfur dioxide emission is used as a parameter to measure the magma movement underneath the volcano towards the surface, according to the experts.

Phivolcs said Taal Volcano was characterized by "weak to voluminous emission of white to dirty white steam-laden plumes 100 to 800 meters tall that drifted southwest".

Meanwhile, the Taal Volcano Network, which can record small tremors undectectable by the Philippine Seismic Network, registered four low-frequency earthquakes over the past 24 hours.

"These earthquakes signify magmatic activity beneath the Taal edifice that could lead to eruptive activity at the main crater," the state seismology agency said.

Alert Level 3 remains over Taal Volcano, which means steam and weak phreatomagmatic explosions, volcanic tremors, ashfall, and lethal volcanic gas expulsions could still occur in the island and nearby lakeshores.

The state seismology warned the communities beside the active river channels to be vigilant during heavy rain as ash could form lahar along the canals.

Entry into the Taal Volcano island, as well as into areas over Taal Lake and the west portion of the island within a 7-kilometer radius from the main crater, was strictly prohibited, Phivolcs said.

The state seismology agency recommended the local government units to assess areas outside the 7-kilometer radius for damage and road worthiness.

It advised people to observe precautions due to ground displacement across fissures, frequent ashfall and minor tremors.

Phivolcs said it would closely monitor Taal Volcano’s activity and any new significant development would be immediately communicated to the public.