4.4

M4.4 Earthquake 33 km NNE of Mejillones, ChileSeptember 16, 2025

2025-09-16 23:53:09 UTC (2025-09-16) · approx. 6:53 PM UTC-5 local

MagnitudeM4.4(mb)
Time23:53 UTC6:53 PM UTC-5
Depth35.0 kmshallow crustal
Coordinates-22.811°, -70.367°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 16, 2025 at 23:53 UTC, a magnitude 4.4 shallow crustal earthquake struck 33 km NNE of Mejillones, Chile, at a depth of 35.0 km and coordinates -22.8107°, -70.3668°.

Physical scale: An earthquake of magnitude 4.4 releases seismic energy equivalent to roughly 60 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 655 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -22.81°, -70.37°

Earthquake Details

Magnitude
4.4 mb
Depth
35.0 km
shallow crustal
Location
-22.8107°N
-70.3668°E

Technical Information

Event ID
us7000qwky
Event Type
earthquake
Status
✓ Reviewed
Significance
298
Stations Used
20
Azimuthal Gap
153.0°
Min Station Distance
0.741°
RMS Residual
0.36 sec
Last Updated
2025-12-03 03:58:47 UTC

Common Questions

How strong was the magnitude 4.4 earthquake near Mejillones, Chile?

The magnitude 4.4 earthquake that struck 33 km NNE of Mejillones, Chile on September 16, 2025 at 23:53 UTC had a depth of 35.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.4 earthquakes can continue for several days and gradually diminish over time.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.

Authoritative source: USGS event page (event ID: us7000qwky). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, September 16, 2025). M4.4 Earthquake 33 km NNE of Mejillones, ChileSeptember 16, 2025. Retrieved May 28, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000qwky/