3.8

M3.8 Earthquake 67 km E of Cruz Bay, U.S. Virgin Islands — March 11, 2021

2021-03-11 21:57:32 UTC (2021-03-11) · approx. 5:57 PM UTC-4 local

MagnitudeM3.8(md)
Time21:57 UTC≈ 5:57 PM UTC-4
Depth79.0 kmintermediate depth
Coordinates18.245°, -64.160°
Felt byNo felt reports
Status✓ Reviewed by USGS

On March 11, 2021 at 21:57 UTC, a magnitude 3.8 intermediate depth earthquake struck 67 km E of Cruz Bay, U.S. Virgin Islands, at a depth of 79.0 km and coordinates 18.2455°, -64.1596°.

Physical scale: An earthquake of magnitude 3.8 releases seismic energy equivalent to roughly 8.1 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 260 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 18.25°, -64.16°

Earthquake Details

Magnitude
3.8 md
Depth
79.0 km
intermediate depth
Location
18.2455°N
-64.1596°E

Technical Information

Event ID
pr2021070007
Event Type
earthquake
Status
✓ Reviewed
Significance
224
Stations Used
14
Azimuthal Gap
187.0°
Min Station Distance
1.102°
RMS Residual
0.70 sec
Last Updated
2021-05-21 19:49:36 UTC

Common Questions

How strong was the magnitude 3.8 earthquake near Cruz Bay, U.S. Virgin Islands?

The magnitude 3.8 earthquake that struck 67 km E of Cruz Bay, U.S. Virgin Islands on March 11, 2021 at 21:57 UTC had a depth of 79.0 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.8 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.8 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: pr2021070007). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, March 11, 2021). M3.8 Earthquake 67 km E of Cruz Bay, U.S. Virgin Islands — March 11, 2021. Retrieved May 21, 2021 from https://www.earthquaketracker.org/earthquakes/event/pr2021070007/