M4.6 Earthquake in the Chagos Archipelago region — August 9, 2021
2021-08-09 18:02:04 UTC (2021-08-09) · approx. 11:02 PM UTC+5 local
On August 9, 2021 at 18:02 UTC, a magnitude 4.6 shallow crustal earthquake struck in the Chagos Archipelago region, at a depth of 10.0 km and coordinates -5.7320°, 69.7984°.
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.

Earthquake Details
69.7984°E
Technical Information
Common Questions
How strong was the magnitude 4.6 earthquake in the Chagos Archipelago region?
The magnitude 4.6 earthquake that struck in the Chagos Archipelago region on August 9, 2021 at 18:02 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 -5.7320°, 69.7984°, which is in the Chagos Archipelago region.
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: us6000f7zf). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, August 9, 2021). M4.6 Earthquake in the Chagos Archipelago region — August 9, 2021. Retrieved October 23, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000f7zf/