On  26  December 2024,  a magnitude (Mw) 5.3  earthquake with  a depth of 12  km struck Talacogon, Agusan del Sur in Eastern Mindanao. This was followed by several aftershocks, of which, the magnitude (Mw) 4.6  with a depth of 7 km was the largest, so far  (Figure 1).

The magnitude  5.3  earthquake was reported to  have been felt  with  a maximum intensity of PHIVOLCS  Earthquake Intensity Scale (PEIS) IV (Moderately Strong) in the City of Bislig and Hinatuan, Surigao del Sur.  The magnitude 4.6  aftershock was also felt with a maximum  intensity of PEIS   IV (Moderately Strong) in Talacogon, Agusan  del  Sur,  and the City  of  Bislig,  Surigao  del Sur.   Based on  SWIFT-CMT solutions, both  earthquakes exhibited strike-slip faulting (horizontal motion along the fault), with the Philippine Fault - Agusan Marsh segment identified as the likely source.

Figure 1. A map displaying the epicentral locations of the magnitude 5.3 and magnitude 4.6 earthquakes on 26 December 2024, as recorded by the DOST-PHIVOLCS Philippine Seismic Network.

The Philippine Fault - Agusan Marsh segment is part of the larger Philippine Fault system that runs through Agusan del Sur. Earthquakes along this segment can also impact neighboring provinces, highlighting the importance of preparedness across the region. While it is not possible to predict the exact timing and magnitude of future earthquakes, these risks should be approached with caution and readiness rather than fear.

DOST-PHIVOLCS continues to monitor the earthquake activity. In the event of a strongly felt earthquake, remember to DUCK (DROP), COVER, AND HOLD.

DUCK (DROP): Get down on the ground to avoid being knocked over.
COVER: Take shelter under a sturdy table, or protect your head and neck with your arms. Stay away from windows, glass, and heavy objects.
HOLD: Hold on to your position until the shaking stops.

Stay alert for aftershocks and the future occurrence of strong earthquakes. Seek technical assistance in the conduct of building inspection to ensure structural safety. Regularly review and test your emergency and contingency plans, identify safe evacuation areas, secure objects indoors so they will not topple or fall on you, prepare an emergency kit or go-bag, and stay informed through reliable sources, such as DOST-PHIVOLCS, Office of Civil Defense (OCD), and your Local Disaster Risk Reduction and Management Offices (LDRRMO).

A recent study of DOST-PHIVOLCS, published on Temblor.net, highlights tectonic stress increases along the Philippine Fault in Mindanao, potentially influenced by recent earthquakes along the Philippine Trench. These findings reinforce the importance of disaster preparedness and encourage communities to prioritize proactive safety measures in their daily lives.

For additional information about the faults and trenches in Mindanao, visit this link.

https://temblor.net/temblor/stress-releases-seismic-gaps-eastern-mindanao-philippines-16147/

https://bit.ly/AgusanDSeq_Dec2024_Eng