Bulusan Volcano’s seismic monitoring network did not detect any volcanic earthquake during the past 24 hours. Degassing at the active vents could not be observed due to thick clouds covering the summit. Sulfur dioxide (SO2) emission was measured at an average of 115 tonnes/day on September 24, 2017. Precise leveling data obtained on August 23 to September 1, 2017 indicated inflationary changes relative to June 2017. Continuous GPS measurements also indicate inflationary trend since July 2016.
Alert Level 1 (abnormal) status remains in effect over Bulusan Volcano, which means that it is currently in a state of unrest probably driven by hydrothermal processes that could generate steam driven or phreatic eruptions. Local government units and the public are reminded that entry into the 4-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited and that vigilance in the Extended Danger Zone (EDZ) must be exercised due to the increased possibilities of sudden and hazardous phreatic eruptions. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden phreatic eruption can be hazardous to aircraft. Furthermore, people living within valleys and along river/stream channels especially on the southeast, southwest and northwest sector of the edifice should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall. DOST-PHIVOLCS is closely monitoring Bulusan Volcano’s condition and any new development will be communicated to all concerned stakeholders.
