File photo of Taal Volcano. —INQUIRER/GRIG C. MONTEGRANDE
LUCENA CITY — After four days of calmness, Taal Volcano in Batangas province recorded five tremors over the last 24 hours, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported on Wednesday, May 29.
In its bulletin, the state volcanologist said the volcanic tremors lasted two to 13 minutes.
Volcanic tremors are “continuous seismic signals with regular or irregular sine wave appearance and low frequencies.”
The volcano has been calm and without earthquakes since May 24.
READ: Phivolcs Taal Volcano update: 8 volcanic quakes in 24 hours
The last sign of unrest around the volcano was on May 23 when the Phivolcs detected three earthquakes accompanied by a volcanic tremor that lasted six minutes.
The state seismologist defined volcanic earthquakes as those that come from an active volcano and are distinguished by their “mode of arrivals, periods, amplitudes, etc.”
In its latest update, Phivolcs reported the emission of 3,164 metric tons (MT) of sulfur dioxide, which rose 900 meters tall on Tuesday, May 28.
However, despite the “moderate emission,” the state volcanologist still observed an “upwelling of hot volcanic fluids in the Main Crater Lake” of Taal Volcano Island (TVI), locally known as “Pulo,” which sits in the middle of Taal Lake.
Taal Volcano is still under alert level 1 (low level of volcanic unrest), Phivolcs said.
The agency reminded the public that Taal Volcano remained in an “abnormal condition” and “should not be interpreted to have ceased unrest nor ceased the threat of eruptive activity.”