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Sarangani Experiences Another Magnitudes 5.5 and 5.6 Aftershocks

July 18, 2026

5–7 minutes

Quick Facts

First Event

Parameter	Details
Magnitude	5.5
Date & Time	18 Jul 2026 – 12:12:48 AM
Epicenter	10 kilometers SW of Balut Island
Depth	17 kilometers
Origin	Tectonic
Reported Intensities
Expected Damage	None
Expected Aftershocks	No
Tsunami Threat	None indicated by PHIVOLCS

Second Event

Parameter	Details
Magnitude	5.6
Date & Time	18 Jul 2026 – 10:23:45 AM
Epicenter	102 kilometers SW of Balut Island
Depth	15 kilometers
Origin	Tectonic
Reported Intensities
Expected Damage	None
Expected Aftershocks	No
Tsunami Threat	None indicated by PHIVOLCS

What Happened?

A magnitude 5.5 tectonic earthquake struck the Province of Davao Occidental at 12:12 a.m. July 18, according to the Philippine Institute of Volcanology and Seismology (PHIVOLCS). The earthquake occurred at a depth of 17 kilometers, with its epicenter located 10 kilometers southwest of Balut Island in the said Province.

PHIVOLCS reported that the earthquake was tectonic in origin, meaning it resulted from the sudden movement of rocks along an active fault beneath the Earth’s surface. Based on the agency’s initial assessment, there were no damage and no aftershocks are to be expected.

At the time of publication, no official reports of casualties or significant structural damage had been released.

A second shaking was reported with a magnitude of 5.6 that struck at 10:23 a.m., 102 kilometers southwest of the same Municipality. It had a depth of 15 kilometers and also tectonic in origin.

No damage and no aftershocks were also expected.

According to Phivolcs, both events are aftershocks of the June 2026 magnitude 7.8 offshore Sarangani quake and that of the magnitude 6.5 offshore Davao Occidental earthquake.

Earthquake Details

First Event

Parameter	Value
Magnitude	5.5
Origin	Tectonic
Depth	17 km
Epicenter	10 km SW of Balut Island (Sarangani)
Coordinates	05.37°N, 125.35°E
Reported Intensities

Second Event

Parameter	Value
Magnitude	5.6
Origin	Tectonic
Depth	15 km
Epicenter	102 km SW of Balut Island (Sarangani)
Coordinates	04.81°N, 124.73°E
Reported Intensities

AI-Assisted Content Disclosure:

The information below was generated with the assistance of artificial intelligence and is provided for general informational and educational purposes only. While every effort has been made to ensure accuracy and clarity, AI-generated content may contain errors, omissions, or interpretations that do not reflect the latest scientific findings or official guidance.

This content should not be considered a definitive or authoritative source for earthquake-related information. Readers are encouraged to verify important details with official agencies such as PHIVOLCS, the Office of Civil Defense (OCD), and other relevant government or scientific institutions before making decisions or taking action.

Always rely on official advisories during emergencies and disaster situations.

What Does Magnitude 5.6 Mean?

A magnitude 5.6 earthquake is classified as a moderate earthquake. It is capable of producing moderate to strong ground shaking over a wide area and may cause light to moderate damage, particularly in communities close to the epicenter and in older or poorly constructed buildings.

People near the epicenter are likely to experience strong shaking that can topple unsecured objects, crack walls, and damage vulnerable structures. Well-designed buildings generally perform well during earthquakes of this size, although some non-structural damage—such as broken windows, fallen ceiling materials, or damaged masonry—may still occur.

Although a magnitude 5.6 earthquake may seem only slightly larger than a magnitude 5.0 event, the difference is substantial. Because the earthquake magnitude scale is logarithmic, a magnitude 5.6 earthquake releases about eight times more energy than a magnitude 5.0 earthquake. While considerably less powerful than a magnitude 6.6 earthquake, it is still capable of causing localized damage, especially if it is shallow and occurs near populated areas.

The severity of an earthquake’s impact depends on more than its magnitude alone. Factors such as the earthquake’s depth, distance from communities, local soil conditions, and the quality of buildings and infrastructure all influence how strongly the earthquake is felt and the extent of any resulting damage.

For comparison, magnitude 5 earthquakes occur regularly in the Philippines. Most cause only minor damage, but shallow events occurring close to populated areas can still disrupt communities and serve as an important reminder that earthquake preparedness should remain a year-round priority.

Why Did This Earthquake Happen?

According to PHIVOLCS, this earthquake was an aftershock associated with the June 2026 magnitude 7.8 offshore Sarangani earthquake and the magnitude 6.5 offshore Davao Occidental earthquake.

After a powerful earthquake, the rocks surrounding the ruptured fault do not immediately return to a stable condition. The main earthquake changes the distribution of stress within the Earth’s crust, causing nearby sections of the fault and surrounding rock formations to readjust. These adjustments produce smaller earthquakes known as aftershocks.

The magnitude 6.5 Davao Occidental earthquake formed part of the continuing seismic sequence following the magnitude 7.8 Sarangani event. The more recent earthquakes represent further adjustments within the same affected offshore region as the crust continues to respond to the stress changes caused by the earlier, larger earthquakes.

Aftershocks can continue for weeks, months, or even longer following a major earthquake. They generally become less frequent and weaker over time, although some may still be strong enough to be widely felt and potentially cause additional damage, particularly to structures already weakened by previous shaking.

These earthquakes do not necessarily indicate that a new major earthquake is developing. Instead, they reflect the continuing geological adjustment of the area following the June 2026 earthquake sequence.

Is There a Tsunami Threat?

Based on the initial PHIVOLCS bulletin, no tsunami warning or advisory was issued for this earthquake.

Most inland earthquakes and many moderate offshore earthquakes do not generate tsunamis. Tsunami warnings are issued only when an earthquake has the characteristics capable of significantly disturbing the seafloor and producing hazardous sea waves.

Residents should always rely on official advisories from PHIVOLCS if an earthquake occurs near the coast.

Could Aftershocks Occur?

If PHIVOLCS indicates aftershocks are expected, residents should anticipate additional earthquakes in the coming hours or days. Aftershocks are a normal part of the earthquake cycle as the Earth’s crust adjusts following the main event.

Most aftershocks are smaller than the main earthquake, although some may still be strong enough to be felt.

Could This Trigger Other Earthquakes?

There is no evidence that this earthquake will trigger a major earthquake elsewhere in the country.

Moderate earthquakes can redistribute stress on nearby faults, but scientists cannot predict whether another earthquake will occur or exactly where it might happen. Each earthquake should be evaluated independently unless geological evidence later establishes a connection.

Key Takeaway

This earthquake serves as another reminder that the Philippines is one of the most seismically active countries in the world. While earthquakes cannot be predicted or prevented, their impacts can be greatly reduced through preparedness, resilient construction, and public awareness.

Residents are encouraged to monitor official updates from PHIVOLCS and local authorities as more information becomes available.