M4.9 Earthquake near West Chile Rise — September 20, 2023
2023-09-20 00:27:17 UTC (2023-09-20) · approx. 6:27 PM UTC-6 local
On September 20, 2023 at 00:27 UTC, a magnitude 4.9 shallow crustal earthquake struck near West Chile Rise, at a depth of 10.0 km and coordinates -36.4701°, -96.9030°. This earthquake was detected by 52 seismic stations with good location accuracy and was assigned a USGS significance rating of 369, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 4.9 releases seismic energy equivalent to roughly 338 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.4 km — a useful intuition for the size of the slip patch on the fault.
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
Earthquake Details
-96.9030°E
Technical Information
Common Questions
How strong was the magnitude 4.9 earthquake near West Chile Rise?
The magnitude 4.9 earthquake that struck near West Chile Rise on September 20, 2023 at 00:27 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at -36.4701°, -96.9030°, which is near West Chile Rise. View all earthquakes in Chile.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.9 earthquakes can continue for several days and gradually diminish over time.
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 4.9 event is significantly smaller than that historical record.
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Location
Authoritative source: USGS event page (event ID: us7000kwuf). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, September 20, 2023). M4.9 Earthquake near West Chile Rise — September 20, 2023. Retrieved December 2, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kwuf/