M4.5 Earthquake 87 km NNW of San Antonio de los Cobres, Argentina — December 6, 2024
2024-12-06 21:52:06 UTC (2024-12-06) · approx. 5:52 PM UTC-4 local
Aftershock of the M5.3 mainshock.
On December 6, 2024 at 21:52 UTC, a magnitude 4.5 intermediate depth earthquake struck 87 km NNW of San Antonio de los Cobres, Argentina, at a depth of 227.8 km and coordinates -23.5003°, -66.6774°. This earthquake was detected by 21 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 312, placing it among routine seismic activity.
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.
This earthquake is part of an ongoing aftershock sequence following the magnitude 5.3 mainshock that occurred 10 days ago 44 km NW of San Antonio de los Cobres, Argentina. Since the mainshock, the USGS has recorded 2 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.

Earthquake Details
-66.6774°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.5 earthquake near San Antonio de los Cobres, Argentina?
The magnitude 4.5 earthquake that struck 87 km NNW of San Antonio de los Cobres, Argentina on December 6, 2024 at 21:52 UTC had a depth of 227.8 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at -23.5003°, -66.6774°, which is 87 km NNW of San Antonio de los Cobres, Argentina.
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.
Is this the same earthquake as the M5.3 one earlier?
No. This magnitude 4.5 earthquake is an aftershock of the larger magnitude 5.3 mainshock that occurred earlier 44 km NW of San Antonio de los Cobres, Argentina. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
Authoritative source: USGS event page (event ID: us7000nwr5). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2024, December 6, 2024). M4.5 Earthquake 87 km NNW of San Antonio de los Cobres, Argentina — December 6, 2024. Retrieved February 15, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000nwr5/