4.5

M4.5 Earthquake 19 km W of Laylay, PhilippinesOctober 3, 2021

2021-10-03 18:33:50 UTC (2021-10-03) · approx. 2:33 AM UTC+8 local

MagnitudeM4.5(mb)
Time18:33 UTC2:33 AM UTC+8
Depth10.0 kmshallow crustal
Coordinates13.440°, 121.637°
Felt byNo felt reports
Status✓ Reviewed by USGS

On October 3, 2021 at 18:33 UTC, a magnitude 4.5 shallow crustal earthquake struck 19 km W of Laylay, Philippines, at a depth of 10.0 km and coordinates 13.4399°, 121.6374°.

Physical scale: An earthquake of magnitude 4.5 releases seismic energy equivalent to roughly 85 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 767 m — 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

Map showing earthquake epicenter at 13.44°, 121.64°

Earthquake Details

Magnitude
4.5 mb
Depth
10.0 km
shallow crustal
Location
13.4399°N
121.6374°E

Technical Information

Event ID
us6000fsp4
Event Type
earthquake
Status
✓ Reviewed
Significance
312
Azimuthal Gap
88.0°
Min Station Distance
8.774°
RMS Residual
0.84 sec
Last Updated
2021-12-10 21:14:19 UTC

Common Questions

How strong was the magnitude 4.5 earthquake near Laylay, Philippines?

The magnitude 4.5 earthquake that struck 19 km W of Laylay, Philippines on October 3, 2021 at 18:33 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 13.4399°, 121.6374°, which is 19 km W of Laylay, Philippines. View all earthquakes in Philippines.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.5 earthquakes can continue for several days 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 4.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000fsp4). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, October 3, 2021). M4.5 Earthquake 19 km W of Laylay, PhilippinesOctober 3, 2021. Retrieved December 10, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000fsp4/