Magnitude 5.6 quake jolts Surigao del Sur; aftershock of earlier tremor — Phivolcs
By Jel Santos
A magnitude 5.6 earthquake struck off the coast of Cagwait, Surigao del Sur, on Saturday night, Oct. 18, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
In its Earthquake Information No. 1, the agency said the quake occurred at 8:31 p.m.
“This is an aftershock of the 2025 October 11 Mw6.0 Offshore Surigao del Sur earthquake,” it stated.
It had a depth of 20 kilometers, Phivolcs added.
The agency said the tremor’s epicenter was about 23 kilometers southeast of Cagwait, Surigao del Sur.
Per Phivolcs, the quake was tectonic in origin, meaning it was caused by the movement of rock layers beneath the Earth’s crust.
Reported intensities were Intensity IV in the City of Bislig, Surigao del Sur, and Intensity I in the City of Davao.
Instrumental intensities were Intensity III in the City of Cabadbaran, Agusan del Norte; City of Digos, Davao del Sur; Nabunturan, Davao de Oro; and the cities of Bislig and Tandag in Surigao del Sur.
The agency said that while it expects no aftershocks, minor damage may still occur.