M4.2 Earthquake 45 km WSW of La Ligua, Chile — July 23, 2026
2026-07-23 07:48:53 UTC (3 hours ago) · approx. 2:48 AM UTC-5 local
On July 23, 2026 at 07:48 UTC, a magnitude 4.2 shallow crustal earthquake struck 45 km WSW of La Ligua, Chile, at a depth of 40.5 km and coordinates -32.6230°, -71.6697°.
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 8 days ago 52 km NNW of Valparaíso, Chile. Since the mainshock, the USGS has recorded 4 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
Earthquake Details
-71.6697°E
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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 45 km WSW of La Ligua, Chile on July 23, 2026 at 07:48 UTC had a depth of 40.5 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: us7000t2mq). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, July 23, 2026). M4.2 Earthquake 45 km WSW of La Ligua, Chile — July 23, 2026. Retrieved July 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000t2mq/