M4.6 Earthquake 36 km NW of Saint John’s, Antigua and Barbuda — October 23, 2021
2021-10-23 22:47:27 UTC (2021-10-23) · approx. 6:47 PM UTC-4 local
Felt by 76 people across nearby locations.
On October 23, 2021 at 22:47 UTC, a magnitude 4.6 intermediate depth earthquake struck 36 km NW of Saint John’s, Antigua and Barbuda, at a depth of 94.0 km and coordinates 17.3061°, -62.1265°.
Physical scale: An earthquake of magnitude 4.6 releases seismic energy equivalent to roughly 120 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 899 m — a useful intuition for the size of the slip patch on the fault.
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 76 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
-62.1265°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.6 earthquake near Saint John’s, Antigua and Barbuda?
The magnitude 4.6 earthquake that struck 36 km NW of Saint John’s, Antigua and Barbuda on October 23, 2021 at 22:47 UTC had a depth of 94.0 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 17.3061°, -62.1265°, which is 36 km NW of Saint John’s, Antigua and Barbuda.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.6 earthquakes can continue for several days and gradually diminish over time.
Actions
Authoritative source: USGS event page (event ID: us6000fx3j). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 23, 2021). M4.6 Earthquake 36 km NW of Saint John’s, Antigua and Barbuda — October 23, 2021. Retrieved January 8, 2022 from https://www.earthquaketracker.org/earthquakes/event/us6000fx3j/