LEGAZPI CITY, Philippines — Citing a decline in Bulusan Volcano’s abnormal parameters in the past weeks, the Philippine Institute of Volcanology and Seismology (Phivolcs) lowered its alert alevel from one to zero yesterday.
Phivolcs said Bulusan’s earthquake activity dropped to baseline levels of two to three per day from July 1 to Aug. 17, with a total of 109 weak events recorded.
“This indicates that rock fracturing within the volcanic system associated with shallow hydrothermal activity has diminished,” the agency said in its latest bulletin.
It said ground deformation indicates short-term inflation since July 2020, but measured horizontal changes indicate that it is being driven by tectonic processes rather than ascending magma.
Sulfur dioxiode emission had its last significant record of 48 tons per day in May.
Phivolcs said emission of steam plumes has been very weak to weak, which means diminished hydrothermal activity.
Phivolcs said it would elevate Bulusan’s status again if abnormal parameters would be observed.