The Philippine Institute of Volcanology and Seismology (Phivolcs) on Monday said Taal Volcano continues to show signs of magmatic unrest that cause volcanic earthquakes and tremors.
Taal, which has been placed under Alert Level 3 since the phreatomagmatic explosion on July 1, also spewed high levels of volcanic sulfur dioxide or SO2 gas emissions and steam-rich plumes, according to Phivolcs.
In its Volcano Bulletin for Taal issued at 8 a.m., Monday, Phivolcs said the Taal Volcano Network recorded 186 volcanic earthquakes from 8 a.m. of July 11 to 8 a.m. of July 12.
It also recorded a total of 176 volcanic tremor events having durations of 1 to 16 minutes.
Meanwhile, high levels of volcanic sulfur dioxide or SO2 gas emissions and steam-rich plumes that rose 1,500 meters were generated from the Taal Main Crater. Sulfur dioxide (SO2) emission averaged 6,421 tonnes/day on 11 July 2021, according to Phivolcs.
At Alert Level 3, magma extruding from the Main Crater could drive explosive eruption. As such, Phivolcs maintained that the entire Taal Volcano Island, which is a Permanent Danger Zone (PDZ), should be kept a “no man’s land.”
It says entry into the island as well as into the high-risk barangays of Agoncillo and Laurel must be prohibited due to the hazards of pyroclastic density currents and volcanic tsunami should strong eruptions occur.
Phivolcs said all activities on Taal Lake should not be allowed at this time as the state agency monitoring volcanic activities nationwide warned communities around the Taal’s lakeshores against possible airborne ash and vog.
Since July 1, flying over Taal Volcano Island is prohibited as airborne ash and ballistic fragments from sudden explosions and pyroclastic density currents such as base surges may pose hazards to aircraft.
Taal Volcano last erupted in January 2020, which sent thousands of residents scampering away from the volcano for safety.