M4.2 Earthquake 33 km NNW of La Serena, Chile — September 23, 2026
2026-09-23 03:07:08 UTC (1 hour ago) · approx. 10:07 PM UTC-5 local
On September 23, 2026 at 03:07 UTC, a magnitude 4.2 shallow crustal earthquake struck 33 km NNW of La Serena, Chile, at a depth of 62.4 km and coordinates -29.6195°, -71.3758°.
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 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 5.1 mainshock that occurred 19 days ago 26 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
-71.3758°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.2 earthquake near La Serena, Chile?
The magnitude 4.2 earthquake that struck 33 km NNW of La Serena, Chile on September 23, 2026 at 03:07 UTC had a depth of 62.4 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 4.2 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.1 one earlier?
No. This magnitude 4.2 earthquake is an aftershock of the larger magnitude 5.1 mainshock that occurred earlier 26 km NW of Coquimbo, Chile. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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Understanding This Data
Magnitude 4.2 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000tx0f). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, September 23, 2026). M4.2 Earthquake 33 km NNW of La Serena, Chile — September 23, 2026. Retrieved September 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000tx0f/