4.0

M4.0 Earthquake 27 km SE of Saipan, Northern Mariana IslandsJuly 8, 2023

2023-07-08 20:51:55 UTC (2023-07-08) · approx. 6:51 AM UTC+10 local

MagnitudeM4.0(mb)
Time20:51 UTC6:51 AM UTC+10
Depth107.0 kmintermediate depth
Coordinates15.039°, 145.940°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 8, 2023 at 20:51 UTC, a magnitude 4.0 intermediate depth earthquake struck 27 km SE of Saipan, Northern Mariana Islands, at a depth of 107.0 km and coordinates 15.0390°, 145.9403°.

Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 15.04°, 145.94°

Earthquake Details

Magnitude
4.0 mb
Depth
107.0 km
intermediate depth
Location
15.0390°N
145.9403°E

Technical Information

Event ID
us7000kfrd
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Stations Used
11
Azimuthal Gap
250.0°
Min Station Distance
0.248°
RMS Residual
0.53 sec
Last Updated
2024-01-18 20:25:58 UTC

Common Questions

How strong was the magnitude 4.0 earthquake near Saipan, Northern Mariana Islands?

The magnitude 4.0 earthquake that struck 27 km SE of Saipan, Northern Mariana Islands on July 8, 2023 at 20:51 UTC had a depth of 107.0 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 4.0 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.0 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000kfrd). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, July 8, 2023). M4.0 Earthquake 27 km SE of Saipan, Northern Mariana IslandsJuly 8, 2023. Retrieved January 18, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000kfrd/