M4.9 Earthquake in the Mariana Islands region — October 31, 2023
2023-10-31 20:26:15 UTC (2023-10-31) · approx. 6:26 AM UTC+10 local
On October 31, 2023 at 20:26 UTC, a magnitude 4.9 shallow crustal earthquake struck in the Mariana Islands region, at a depth of 10.0 km and coordinates 20.0752°, 147.6871°. This earthquake was detected by 180 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 369, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 4.9 releases seismic energy equivalent to roughly 338 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.4 km — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
147.6871°E
Technical Information
Common Questions
How strong was the magnitude 4.9 earthquake in the Mariana Islands region?
The magnitude 4.9 earthquake that struck in the Mariana Islands region on October 31, 2023 at 20:26 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 20.0752°, 147.6871°, which is in the Mariana Islands region.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.9 earthquakes can continue for several days and gradually diminish over time.
Actions
Authoritative source: USGS event page (event ID: us7000l7x8). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, October 31, 2023). M4.9 Earthquake in the Mariana Islands region — October 31, 2023. Retrieved January 10, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000l7x8/