M4.8 Earthquake 23 km SW of San Antonio, Chile — October 12, 2026
2026-10-12 18:17:18 UTC (1 hour ago) · approx. 1:17 PM UTC-5 local
Felt by 8 people across nearby locations. Aftershock of the M5.2 mainshock.
On October 12, 2026 at 18:17 UTC, a magnitude 4.8 shallow crustal earthquake struck 23 km SW of San Antonio, Chile, at a depth of 33.6 km and coordinates -33.7210°, -71.8113°. This earthquake was detected by 47 seismic stations with good location accuracy and was assigned a USGS significance rating of 358, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 km — 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 5.2 mainshock that occurred 17 days ago 69 km SW of San Antonio, 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.
The epicenter is located in Chile, a region characterized by the Peru-Chile Trench, where the Nazca Plate subducts beneath South America at 65-80 mm per year. The nearest mapped fault system is the Peru-Chile Trench. View all earthquakes in Chile.
Learn more: Magnitude scale · Aftershock sequences
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 8 citizen responses 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
-71.8113°E
Technical Information
Common Questions
How strong was the magnitude 4.8 earthquake near San Antonio, Chile?
The magnitude 4.8 earthquake that struck 23 km SW of San Antonio, Chile on October 12, 2026 at 18:17 UTC had a depth of 33.6 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at -33.7210°, -71.8113°, which is 23 km SW of San Antonio, Chile. View all earthquakes in Chile.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.2 one earlier?
No. This magnitude 4.8 earthquake is an aftershock of the larger magnitude 5.2 mainshock that occurred earlier 69 km SW of San Antonio, Chile. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
Has Chile had earthquakes this big before?
The largest recorded earthquake in Chile was the M9.5 Great Chilean earthquake of May 22, 1960. Today's magnitude 4.8 event is significantly smaller than that historical record.
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Location
Authoritative source: USGS event page (event ID: us6000u1uq). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, October 12, 2026). M4.8 Earthquake 23 km SW of San Antonio, Chile — October 12, 2026. Retrieved October 12, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000u1uq/