4.4

M4.4 Earthquake 120 km S of Isangel, VanuatuOctober 11, 2023

2023-10-11 20:07:17 UTC (2023-10-11) · approx. 7:07 AM UTC+11 local

MagnitudeM4.4(mb)
Time20:07 UTC7:07 AM UTC+11
Depth52.9 kmshallow crustal
Coordinates-20.631°, 169.367°
Felt byNo felt reports
Status✓ Reviewed by USGS

On October 11, 2023 at 20:07 UTC, a magnitude 4.4 shallow crustal earthquake struck 120 km S of Isangel, Vanuatu, at a depth of 52.9 km and coordinates -20.6313°, 169.3672°.

Physical scale: An earthquake of magnitude 4.4 releases seismic energy equivalent to roughly 60 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 655 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 3 days ago 87 km S of Isangel, Vanuatu. 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.

Map showing earthquake epicenter at -20.63°, 169.37°

Earthquake Details

Magnitude
4.4 mb
Depth
52.9 km
shallow crustal
Location
-20.6313°N
169.3672°E

Technical Information

Event ID
us6000lg5s
Event Type
earthquake
Status
✓ Reviewed
Significance
298
Stations Used
22
Azimuthal Gap
80.0°
Min Station Distance
2.661°
RMS Residual
0.87 sec
Last Updated
2023-12-16 22:13:09 UTC

Common Questions

How strong was the magnitude 4.4 earthquake near Isangel, Vanuatu?

The magnitude 4.4 earthquake that struck 120 km S of Isangel, Vanuatu on October 11, 2023 at 20:07 UTC had a depth of 52.9 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 4.4 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 4.4 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier 87 km S of Isangel, Vanuatu. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

Understanding This Data

Magnitude 4.4 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000lg5s). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, October 11, 2023). M4.4 Earthquake 120 km S of Isangel, VanuatuOctober 11, 2023. Retrieved December 16, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000lg5s/