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BULUSAN VOLCANO BULLETIN 30 December 2016 8:00 A.M. PDF Print
Friday, 30 December 2016 07:42

Bulusan Volcano generated a phreatic eruption from its southeast vent yesterday, 29 December, at 2:40 PM. The event was recorded as an explosion-type earthquake that lasted approximately 16 minutes based on the seismic record. This event produced a grayish to dirty white ash plume 2 kilometers high that drifted towards the general west-southwest direction. Thin ash fell on the Barangays of Cogon, Tinampo, Bolos, Umagom, Gulang-gulang and Monbon of Irosin and Caladgao and Guruyan of Juban, Sorsogon Province. Sufuric smell was experienced in Brgys. Guruyan, Juban and Monbon and Tinampo, Irosin. In addition, Bulusan’s seismic network recorded a total of twenty-two (22) volcanic earthquakes during the past 24 hours. Sulfur dioxide (SO2) emission was measured at an average of 60 tonnes/day on December 24, 2016. Precise leveling data obtained on October 17-23, 2016 indicated inflationary changes of the edifice relative to August 2016. Inflation was also recorded by continuous GPS measurements as of December 2, 2016, indicating pressurization beneath the volcano edifice.

Alert Level 1 (abnormal) remains in effect over Bulusan Volcano. This indicates that hydrothermal processes are underway beneath the volcano that may lead to 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.