On 8 June, a major earthquake with a magnitude of 7.8 hit Sarangani and surrounding provinces, with an offshore epicenter located 32 kilometers west of Maasim, Sarangani, at an estimated depth of 33 kilometers.

According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS), the event may be attributed to subduction along the Cotabato Trench.

As of 8 a.m. on Friday, a total of 46 dead, 688 injured, and 38 missing persons were confirmed after validation and verification of reports.

Meanwhile, using the PHIVOLCS Earthquake Intensity Scale (PEIS), the highest reported intensity was PEIS VII, labeled as “destructive,” which was felt in General Santos City, and ground shaking was felt as far as Abuyog and Dulag in Leyte at PEIS II, which is “slightly felt.”

Aftershocks may be expected to continue for several days to weeks, and some may be felt in nearby provinces.

Alongside this, tsunami waves were recorded along the coasts of Kiamba and Maasim in Sarangani, and Kalamansig in Sultan Kudarat, with heights of approximately one meter based on data from DOST-PHIVOLCS Sea Level Monitoring Stations.

Tsunami waves less than one meter in height were also recorded in Mati City and Zamboanga City.

Following this, PHIVOLCS issued a Tsunami Warning for a destructive tsunami affecting the coasts of Sarangani, Davao Occidental, Tawi-Tawi, Sulu, Basilan, Zamboanga del Sur, Zamboanga Sibugay, Sultan Kudarat, and South Cotabato.

Other hazards

Earthquake-induced landslides, rockfalls, and other forms of mass movement may occur in mountainous and hilly areas.

Active river channels and coastal areas may also be vulnerable to seawater flood due to liquefaction-induced subsidence and changes in sea level, including sinkholes in areas underlain by limestone bedrock.

On the other hand, PHVOLCS reminded the public that earthquakes do not result from active volcanoes.

However, in line with standard monitoring protocols for moderate to great earthquakes occurring near active volcanoes, DOST-PHIVOLCS assured the public that it will continue to closely monitor the area for any volcanic activity that may be affected by the event.