M4.9 Earthquake near Southwest Indian Ridge — October 23, 2021
2021-10-23 14:17:52 UTC (2021-10-23) · approx. 5:17 PM UTC+3 local
On October 23, 2021 at 14:17 UTC, a magnitude 4.9 shallow crustal earthquake struck near Southwest Indian Ridge, at a depth of 10.0 km and coordinates -37.5156°, 50.9295°.
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.
Earthquake Details
50.9295°E
Technical Information
Common Questions
How strong was the magnitude 4.9 earthquake near Southwest Indian Ridge?
The magnitude 4.9 earthquake that struck near Southwest Indian Ridge on October 23, 2021 at 14:17 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 -37.5156°, 50.9295°, which is near Southwest Indian Ridge.
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.
Actions
Location
Authoritative source: USGS event page (event ID: us6000fx15). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 23, 2021). M4.9 Earthquake near Southwest Indian Ridge — October 23, 2021. Retrieved January 8, 2022 from https://www.earthquaketracker.org/earthquakes/event/us6000fx15/