5.5

M5.5 Earthquake 61 km N of Namuac, PhilippinesJune 17, 2023

2023-06-17 10:15:20 UTC (2023-06-17) · approx. 6:15 PM UTC+8 local

Maximum shaking intensity MMI 4.1 (moderate).

MagnitudeM5.5(mww)
Time10:15 UTC6:15 PM UTC+8
Depth36.3 kmshallow crustal
Coordinates19.162°, 121.204°
Felt byNo felt reports
Status✓ Reviewed by USGS· green PAGER
green Alertno significant casualties or damage expected

On June 17, 2023 at 10:15 UTC, a magnitude 5.5 shallow crustal earthquake struck 61 km N of Namuac, Philippines, at a depth of 36.3 km and coordinates 19.1623°, 121.2038°. The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 127 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 465, placing it among routine seismic activity. The nearest populated place is Claveria (population 10,618).

Physical scale: An earthquake of magnitude 5.5 releases seismic energy equivalent to roughly 3 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 3.8 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Philippines, a region characterized by the Manila Trench and Philippine Trench subduction systems, where the Philippine Sea Plate overrides the Eurasian Plate. The nearest mapped fault system is the Philippine Fault. View all earthquakes in Philippines.

Learn more: Magnitude scale · Aftershock sequences

Nearest Populated Places

Claveriapop. 10,618
MMI 3.5 (light)
Namuacpop. 3,037
MMI 3.5 (light)
Santa Cruzpop. 2,295
MMI 3.4 (light)
Abulugpop. 2,412
MMI 3.4 (light)
Pamplonapop. 2,133
MMI 3.4 (light)
Pagudpudpop. 4,945
MMI 3.4 (light)
Map showing earthquake epicenter at 19.16°, 121.20°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M5.5 earthquake near 61 km N of Namuac, Philippines

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Population exposure (USGS PAGER)

Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.

Shaking intensity (MMI)DescriptionPopulation exposed
MMI 3weak3,161,930
MMI 4light75,310

Earthquake Details

Magnitude
5.5 mww
Depth
36.3 km
shallow crustal
Location
19.1623°N
121.2038°E
Intensity (MMI)
4.1
moderate

Technical Information

Event ID
us7000k96f
Event Type
earthquake
Status
✓ Reviewed
Significance
465
Stations Used
127
Azimuthal Gap
39.0°
Min Station Distance
3.639°
RMS Residual
0.49 sec
Last Updated
2023-08-21 04:19:18 UTC

Common Questions

How strong was the magnitude 5.5 earthquake near Namuac, Philippines?

The magnitude 5.5 earthquake that struck 61 km N of Namuac, Philippines on June 17, 2023 at 10:15 UTC had a depth of 36.3 km. For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 19.1623°, 121.2038°, which is 61 km N of Namuac, Philippines. The nearest populated place is Claveria (population 10,618). View all earthquakes in Philippines.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.5 earthquakes can continue for days to weeks and gradually diminish over time.

Has Philippines had earthquakes this big before?

The largest recorded earthquake in Philippines was the M8.0 Mindanao earthquake of August 17, 1976. Today's magnitude 5.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000k96f). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, June 17, 2023). M5.5 Earthquake 61 km N of Namuac, PhilippinesJune 17, 2023. Retrieved August 21, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000k96f/