M3.9 Earthquake in the Pagan region, Northern Mariana Islands — March 15, 2025
2025-03-15 20:41:03 UTC (2025-03-15) · approx. 6:41 AM UTC+10 local
On March 15, 2025 at 20:41 UTC, a magnitude 3.9 intermediate depth earthquake struck in the Pagan region, Northern Mariana Islands, at a depth of 146.7 km and coordinates 18.4857°, 145.7622°.
Physical scale: An earthquake of magnitude 3.9 releases seismic energy equivalent to roughly 11 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 296 m — 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 13 days ago in the Pagan region, Northern Mariana Islands. 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
145.7622°E
Technical Information
Common Questions
How strong was the magnitude 3.9 earthquake in the Pagan region, Northern Mariana Islands?
The magnitude 3.9 earthquake that struck in the Pagan region, Northern Mariana Islands on March 15, 2025 at 20:41 UTC had a depth of 146.7 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 3.9 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 3.9 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier in the Pagan region, Northern Mariana Islands. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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Understanding This Data
Magnitude 3.9 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us7000pmaa). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, March 15, 2025). M3.9 Earthquake in the Pagan region, Northern Mariana Islands — March 15, 2025. Retrieved May 17, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000pmaa/