M5.5 Earthquake near Union, Philippines — 27 December 2024
A moderate earthquake of magnitude 5.5 was recorded near Union, Philippines on , with an epicentre 34 km southeast of Union, at a focal depth of 56.1 km.
Time (UTC): 2024-12-27 18:42:58
Time (your timezone): —
Magnitude: 5.5 (moderate)
Focal depth: 56.1 km (shallow)
Epicentre: 9.5628, 126.3600
Location: 34 km SE of Union, Philippines
USGS link to NOAA tsunami information: Not linked
Review status: Reviewed
Source: USGS event page
How strong was this earthquake?
Moderate earthquakes can damage poorly built or unreinforced structures near the epicentre, while well-engineered buildings typically escape serious harm. Shaking is often strong enough to wake sleeping residents over a wide area.
A magnitude 5.5 earthquake radiates roughly 2,682 tons of TNT equivalent in seismic energy.
The USGS assigns this earthquake a significance score of 469, which is below the USGS threshold of more than 600 for its significant-earthquake list. The ranking combines magnitude with available Did You Feel It responses and PAGER alert level; it is not a direct measurement of damage.
Where was the epicentre?
The epicentre was located at 9.5628, 126.3600 — 34 km southeast of Union. The closest other recorded event was a magnitude 4.9 earthquake 20 km south-southeast of here on 04 February 2026.
Why the 56 km depth matters
At 56 km this was a shallow earthquake. Shallow events release their energy close to the surface, so for a given magnitude they produce noticeably stronger shaking — and more damage — than deeper ones. Roughly three quarters of all earthquakes worldwide occur at shallow depths.
This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, an event this size can be felt widely and may cause minor local damage. Its shallow focus makes stronger surface shaking more likely than for a deeper event of the same magnitude.
What does the tsunami information flag mean?
The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M5.5 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.
How earthquakes generate tsunamis, and what the alert levels mean →
Aftershocks and local seismic history
No further earthquakes have been recorded within about 150 km of the epicentre in the seven days after this event.
103 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 6.1 event near Union on 16 October 2025. This M5.5 event released about 7.9 times less energy than that event.
How long aftershock sequences last, and how large they get →
Where this event sits in the record
This earthquake is part of the December 2024 worldwide record. Browse the full monthly archive to compare periods.
Nearest recorded earthquakes to this epicentre
- M4.9 earthquake near Cortes, Philippines — (20 km SSE)
- M4.8 earthquake near Union, Philippines — (24 km NW)
- M5.5 earthquake near Cortes, Philippines — (29 km S)
- M4.8 earthquake near Union, Philippines — (30 km NW)
- M6.1 earthquake near Union, Philippines — (35 km NW)
- M5.0 earthquake near La Paz, Philippines — (54 km SSE)
- M4.5 earthquake near Carmen, Philippines — (56 km SW)
- M4.5 earthquake near Bacolod, Philippines — (58 km SSE)
- M4.7 earthquake near Bacolod, Philippines — (58 km SSE)
- M4.8 earthquake near Libas, Philippines — (59 km NW)
Other magnitude 5 earthquakes worldwide
- M5.6 earthquake near Port McNeill, Canada —
- M5.5 earthquake near Mutsu, Japan —
- M5.6 earthquake near San Fernando, Peru —
- M5.4 earthquake near Abepura, Indonesia —
- M5.3 earthquake near Kokopo, Papua New Guinea —
- M5.6 earthquake near Pacific-Antarctic Ridge —
- M5.4 earthquake near Rapu-Rapu, Philippines —
- M5.4 earthquake near Tsunagi, Japan —
Questions about this earthquake
How strong is a magnitude 5.5 earthquake?
Moderate earthquakes can damage poorly built or unreinforced structures near the epicentre, while well-engineered buildings typically escape serious harm. Shaking is often strong enough to wake sleeping residents over a wide area. A magnitude 5.5 earthquake radiates roughly 2,682 tons of TNT equivalent in seismic energy.
How deep was the earthquake near Union?
At 56 km this was a shallow earthquake. Shallow events release their energy close to the surface, so for a given magnitude they produce noticeably stronger shaking — and more damage — than deeper ones. Roughly three quarters of all earthquakes worldwide occur at shallow depths.
Was the M5.5 earthquake near Union felt?
This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, an event this size can be felt widely and may cause minor local damage. Its shallow focus makes stronger surface shaking more likely than for a deeper event of the same magnitude.
What does the USGS tsunami field mean for this event?
The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M5.5 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.
Have there been aftershocks?
No further earthquakes have been recorded within about 150 km of the epicentre in the seven days after this event.
How often do earthquakes happen near Union?
103 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 6.1 event near Union on 16 October 2025. This M5.5 event released about 7.9 times less energy than that event.