M4.2 Earthquake 68 km W of La Ligua, Chile — September 28, 2025
2025-09-28 21:31:07 UTC (2025-09-28) · approx. 4:31 PM UTC-5 local
On September 28, 2025 at 21:31 UTC, a magnitude 4.2 shallow crustal earthquake struck 68 km W of La Ligua, Chile, at a depth of 30.2 km and coordinates -32.3472°, -71.9528°.
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 3 days ago 52 km NNW of Valparaíso, Chile. Since the mainshock, the USGS has recorded 3 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-71.9528°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.2 earthquake near La Ligua, Chile?
The magnitude 4.2 earthquake that struck 68 km W of La Ligua, Chile on September 28, 2025 at 21:31 UTC had a depth of 30.2 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 52 km NNW of Valparaíso, 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: us6000rdhs). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, September 28, 2025). M4.2 Earthquake 68 km W of La Ligua, Chile — September 28, 2025. Retrieved December 11, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000rdhs/