Tsunami waves were recorded in six coastal areas in Mindanao following the magnitude 7.8 earthquake that struck off Sarangani province on Monday morning, according to Phivolcs.
The agency said the waves were observed in Maasim and Kiamba in Sarangani, Kalamansig in Sultan Kudarat, Mati City in Davao Oriental, Zamboanga City, and Tandag City in Surigao del Sur.
Wave arrival times ranged from 7:42 a.m. to 8:45 a.m., with Maasim recording the earliest surge and Tandag City the latest based on monitoring data.
Phivolcs said wave heights differed per area, with the highest reaching up to 1.4 meters above normal sea level.
The agency maintained that the tsunami advisory remained in effect as of the latest bulletin, with no lifting announced.
Meanwhile, aftershocks continued to follow the quake, with Phivolcs logging 138 tremors as of 11 a.m.
Only nine of the aftershocks were felt by residents, with magnitudes ranging from 1.3 to 6.7.
The Philippines, situated along the Pacific Ring of Fire, remains prone to frequent earthquakes and related seismic activity due to constant tectonic movement.
