4.2

M4.2 Earthquake in the Alamagan region, Northern Mariana IslandsNovember 24, 2025

2025-11-24 23:29:04 UTC (2025-11-24) · approx. 9:29 AM UTC+10 local

MagnitudeM4.2(mb)
Time23:29 UTC9:29 AM UTC+10
Depth99.7 kmintermediate depth
Coordinates17.959°, 146.144°
Felt byNo felt reports
Status✓ Reviewed by USGS

On November 24, 2025 at 23:29 UTC, a magnitude 4.2 intermediate depth earthquake struck in the Alamagan region, Northern Mariana Islands, at a depth of 99.7 km and coordinates 17.9587°, 146.1439°.

Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 17.96°, 146.14°

Earthquake Details

Magnitude
4.2 mb
Depth
99.7 km
intermediate depth
Location
17.9587°N
146.1439°E

Technical Information

Event ID
us6000ru76
Event Type
earthquake
Status
✓ Reviewed
Significance
271
Stations Used
19
Azimuthal Gap
156.0°
Min Station Distance
2.724°
RMS Residual
0.39 sec
Last Updated
2026-02-20 16:07:39 UTC

Common Questions

How strong was the magnitude 4.2 earthquake in the Alamagan region, Northern Mariana Islands?

The magnitude 4.2 earthquake that struck in the Alamagan region, Northern Mariana Islands on November 24, 2025 at 23:29 UTC had a depth of 99.7 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.2 earthquakes can continue for several days and gradually diminish over time.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.

Authoritative source: USGS event page (event ID: us6000ru76). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, November 24, 2025). M4.2 Earthquake in the Alamagan region, Northern Mariana IslandsNovember 24, 2025. Retrieved May 25, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000ru76/