The Philippine Institute of Volcanology and Seismology (Phivolcs) has urged residents of Bohol to remain vigilant against potential earthquakes, warning that unlike typhoons, tremors cannot be predicted in advance.
Nolan Evangelista, Phivolcs Bohol provincial head, said the public should stay alert at all times since no technology currently exists that can accurately forecast when or where an earthquake will strike.
He noted that even the magnitude 7.8 earthquake that struck Mindanao was not anticipated by experts, despite it being among the strongest to hit the Philippines in the past 50 years, killing dozens and injuring scores of people.
Evangelista said Bohol remains at high risk because the province sits atop several fault systems, including the one responsible for the deadly 2013 earthquake that killed more than 200 people and damaged centuries-old churches across the province.
He added that other faults in Bohol have yet to move and could generate the province’s next major earthquake.
According to Evangelista, the southern part of Bohol contains numerous dormant fault lines that could be activated at any time, including a notable fault affecting towns from Anda to Maribojoc.
He also pointed to offshore trenches near Bohol’s coastline capable of generating strong earthquakes and, in some cases, tsunamis.
His warning comes as Phivolcs separately cautioned that communities near six major active trenches nationwide — the Philippine Trench, East Luzon Trough, Manila Trench, Negros Trench, Sulu Trench and Cotabato Trench — could experience earthquakes as strong as magnitude 8.2.
Phivolcs Director Teresito Bacolcol said any segment of these trenches could generate a powerful quake depending on tectonic plate movement beneath the seabed.
The nationwide alert followed the magnitude 7.8 earthquake that struck offshore Sarangani on June 8, 2026 which Phivolcs attributed to movement along the Cotabato Trench.
The Philippines sits along the Pacific Ring of Fire, a zone of intense seismic and volcanic activity where thousands of tremors — most too weak to be felt — are recorded annually.
Phivolcs urged local governments and residents in earthquake-prone areas, including Bohol, to strengthen preparedness measures such as emergency response plans and public awareness campaigns.