4.8

M4.8 Earthquake southeast of the Loyalty IslandsJuly 18, 2023

2023-07-18 01:09:18 UTC (2023-07-18) · approx. 12:09 PM UTC+11 local

MagnitudeM4.8(mb)
Time01:09 UTC12:09 PM UTC+11
Depth113.1 kmintermediate depth
Coordinates-22.137°, 171.219°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 18, 2023 at 01:09 UTC, a magnitude 4.8 intermediate depth earthquake struck southeast of the Loyalty Islands, at a depth of 113.1 km and coordinates -22.1367°, 171.2191°. This earthquake was detected by 82 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 354, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 km — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -22.14°, 171.22°

Earthquake Details

Magnitude
4.8 mb
Depth
113.1 km
intermediate depth
Location
-22.1367°N
171.2191°E

Technical Information

Event ID
us7000kghy
Event Type
earthquake
Status
✓ Reviewed
Significance
354
Stations Used
82
Azimuthal Gap
63.0°
Min Station Distance
3.524°
RMS Residual
0.50 sec
Last Updated
2023-09-28 21:33:42 UTC

Common Questions

How strong was the magnitude 4.8 earthquake southeast of the Loyalty Islands?

The magnitude 4.8 earthquake that struck southeast of the Loyalty Islands on July 18, 2023 at 01:09 UTC had a depth of 113.1 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at -22.1367°, 171.2191°, which is southeast of the Loyalty Islands.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 earthquakes can continue for several days and gradually diminish over time.

Authoritative source: USGS event page (event ID: us7000kghy). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, July 18, 2023). M4.8 Earthquake southeast of the Loyalty IslandsJuly 18, 2023. Retrieved September 28, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kghy/