4.0

M4.0 Earthquake 51 km NE of Calama, ChileNovember 3, 2025

2025-11-03 21:22:01 UTC (2025-11-03) · approx. 4:22 PM UTC-5 local

MagnitudeM4.0(mb)
Time21:22 UTC4:22 PM UTC-5
Depth121.8 kmintermediate depth
Coordinates-22.094°, -68.617°
Felt byNo felt reports
Status✓ Reviewed by USGS

On November 3, 2025 at 21:22 UTC, a magnitude 4.0 intermediate depth earthquake struck 51 km NE of Calama, Chile, at a depth of 121.8 km and coordinates -22.0936°, -68.6170°.

Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — a useful intuition for the size of the slip patch on the fault.

This earthquake is part of an ongoing aftershock sequence following the magnitude 6.9 mainshock that occurred 8 hours ago 29 km ENE of Calama, Chile. Since the mainshock, the USGS has recorded 4 aftershocks in this area. Aftershock activity is expected to continue for weeks to months as stresses on surrounding faults redistribute.

Map showing earthquake epicenter at -22.09°, -68.62°

Earthquake Details

Magnitude
4.0 mb
Depth
121.8 km
intermediate depth
Location
-22.0936°N
-68.6170°E

Technical Information

Event ID
us6000rl8x
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Stations Used
19
Azimuthal Gap
85.0°
Min Station Distance
0.651°
RMS Residual
0.70 sec
Last Updated
2026-01-27 17:59:07 UTC

Common Questions

How strong was the magnitude 4.0 earthquake near Calama, Chile?

The magnitude 4.0 earthquake that struck 51 km NE of Calama, Chile on November 3, 2025 at 21:22 UTC had a depth of 121.8 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 4.0 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M6.9 one earlier?

No. This magnitude 4.0 earthquake is an aftershock of the larger magnitude 6.9 mainshock that occurred earlier 29 km ENE of Calama, Chile. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

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: us6000rl8x). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, November 3, 2025). M4.0 Earthquake 51 km NE of Calama, ChileNovember 3, 2025. Retrieved May 26, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000rl8x/