M4.3 Earthquake 78 km WNW of Coquimbo, Chile — October 1, 2025
2025-10-01 16:08:04 UTC (2025-10-01) · approx. 11:08 AM UTC-5 local
On October 1, 2025 at 16:08 UTC, a magnitude 4.3 shallow crustal earthquake struck 78 km WNW of Coquimbo, Chile, at a depth of 21.9 km and coordinates -29.6153°, -72.0580°.
Physical scale: An earthquake of magnitude 4.3 releases seismic energy equivalent to roughly 43 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 558 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 5.0 mainshock that occurred 12 days ago 96 km NW of Coquimbo, Chile. Since the mainshock, the USGS has recorded 1 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
Earthquake Details
-72.0580°E
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Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.3 earthquake near Coquimbo, Chile?
The magnitude 4.3 earthquake that struck 78 km WNW of Coquimbo, Chile on October 1, 2025 at 16:08 UTC had a depth of 21.9 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 4.3 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.0 one earlier?
No. This magnitude 4.3 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier 96 km NW of Coquimbo, Chile. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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Understanding This Data
Magnitude 4.3 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000re0g). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, October 1, 2025). M4.3 Earthquake 78 km WNW of Coquimbo, Chile — October 1, 2025. Retrieved December 19, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000re0g/