M4.8 Earthquake near Mid-Indian Ridge — July 21, 2026
2026-07-21 03:19:54 UTC (2026-07-21) · approx. 8:19 AM UTC+5 local
Aftershock of the M5.0 mainshock.
On July 21, 2026 at 03:19 UTC, a magnitude 4.8 shallow crustal earthquake struck near Mid-Indian Ridge, at a depth of 10.0 km and coordinates -27.9680°, 74.1519°. This earthquake was detected by 31 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 354, 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 5.0 mainshock that occurred 19 days ago near Mid-Indian Ridge. Since the mainshock, the USGS has recorded 0 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
Earthquake Details
74.1519°E
Technical Information
Common Questions
How strong was the magnitude 4.8 earthquake near Mid-Indian Ridge?
The magnitude 4.8 earthquake that struck near Mid-Indian Ridge on July 21, 2026 at 03:19 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 -27.9680°, 74.1519°, which is near Mid-Indian Ridge.
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 M5.0 one earlier?
No. This magnitude 4.8 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier near Mid-Indian Ridge. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
Actions
Location
Authoritative source: USGS event page (event ID: us6000tg3i). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, July 21, 2026). M4.8 Earthquake near Mid-Indian Ridge — July 21, 2026. Retrieved August 3, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000tg3i/