The Philippine Institute of Volcanology and Seismology (Phivolcs) said four “minor” but “successive” phreatic or steam-driven eruptions occurred at Taal Volcano on Thursday, May 16.

In its 7 p.m. advisory, Phivolcs explained that the activity is likely driven by the continued emission of hot volcanic gases at the Taal Main Crater.  

Phivolcs said the phreatic eruption events at the Taal’s main crater were observed from 8:54 a.m. to 8:57 a.m., 11:07 a.m. to 11:10 a.m., 1:48 p.m. to 1:50 p.m., and 5:37 p.m.

The steam-laden plumes rose between 50 and 300 meters above the Main Crater before drifting west-northwest, it added.

It also reported a sulfur dioxide flux of 5,094 tons per day since May 13.

Although the background levels of volcanic earthquake activity and ground deformation detected at Taal indicate that unrest is unlikely to progress into a magmatic eruption.

Phivolcs said Alert Level 1 is maintained, which means that areas within its vicinity could still be threatened by sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas.

The Taal Volcano is still in “abnormal condition” and should not be interpreted to have ceased unrest nor ceased the threat of eruptive activity, it added.

Moreover, Phivolcs reminded the public of the prohibition of entry into Taal's Permanent Danger Zone (PDZ), particularly in the vicinities of the Main Crater and the Daang Kastila fissure.