An official from the Philippine Institute of Volcanology and Seismology (Phivolcs) has urged authorities to check the structural integrity of infrastructures in Samar and Leyte after multiple earthquakes occurred off the coast of Eastern Samar.

Dr. Winchelle Ian Sevilla, Chief Science Research Specialist of Phivolcs' Volcano Monitoring and Eruption Prediction Division, emphasized the importance of residents inspecting their homes to ensure they have not been damaged by the offshore earthquakes.

“Residents must be aware of potential aftershocks, follow the local government's instructions, and consult with local engineers,” Sevilla said in a phone interview.

Last Sunday night, the state seismology agency recorded two magnitude 4 aftershocks, following a magnitude 5.3 earthquake that occurred on the evening of Friday, 14 February.

Initial inspections by the Local Disaster Risk Reduction and Management Office (LDRRMO) of Hernani revealed minimal cracks in various establishments in the area.

Sevilla explained that the earthquake was triggered by the Philippine Trench, a 1,320-kilometer-long trench extending from the east of Luzon to Indonesia.

“It is normal for trenches to generate earthquakes, although more frequent tremors tend to occur along fault lines,” the state seismologist added.

Since the 14 February earthquake, Phivolcs has recorded 129 tremors, of which 74 were plotted.

The strongest aftershock occurred at 9:18 a.m. on 15 February, with a magnitude of 5.2, felt across the Samar provinces, Leyte, Masbate, and Sorsogon.

Phivolcs also noted that the aftershocks, primarily in the areas of Maydolong and Hernani in Eastern Samar, are all tectonic in origin.