4.0

M4.0 Earthquake 55 km NNE of Calama, Chile — December 20, 2020

2020-12-20 22:20:03 UTC (2020-12-20) · approx. 5:20 PM UTC-5 local

MagnitudeM4.0(mb)
Time22:20 UTC≈ 5:20 PM UTC-5
Depth121.3 kmintermediate depth
Coordinates-22.005°, -68.683°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 20, 2020 at 22:20 UTC, a magnitude 4.0 intermediate depth earthquake struck 55 km NNE of Calama, Chile, at a depth of 121.3 km and coordinates -22.0051°, -68.6830°.

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.

Map showing earthquake epicenter at -22.01°, -68.68°

Earthquake Details

Magnitude
4.0 mb
Depth
121.3 km
intermediate depth
Location
-22.0051°N
-68.6830°E

Technical Information

Event ID
us7000csse
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Azimuthal Gap
46.0°
Min Station Distance
0.559°
RMS Residual
0.64 sec
Last Updated
2021-02-27 23:26:40 UTC

Common Questions

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

The magnitude 4.0 earthquake that struck 55 km NNE of Calama, Chile on December 20, 2020 at 22:20 UTC had a depth of 121.3 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.

Understanding This Data

Magnitude 4.0 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000csse). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2020, December 20, 2020). M4.0 Earthquake 55 km NNE of Calama, Chile — December 20, 2020. Retrieved February 27, 2021 from https://www.earthquaketracker.org/earthquakes/event/us7000csse/