4.2

M4.2 Earthquake 123 km WNW of Hihifo, TongaApril 9, 2023

2023-04-09 22:18:32 UTC (2023-04-09) · approx. 10:18 AM UTC-12 local

MagnitudeM4.2(mb)
Time22:18 UTC10:18 AM UTC-12
Depth268.6 kmintermediate depth
Coordinates-15.679°, -174.915°
Felt byNo felt reports
Status✓ Reviewed by USGS

On April 9, 2023 at 22:18 UTC, a magnitude 4.2 intermediate depth earthquake struck 123 km WNW of Hihifo, Tonga, at a depth of 268.6 km and coordinates -15.6790°, -174.9149°.

Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -15.68°, -174.91°

Earthquake Details

Magnitude
4.2 mb
Depth
268.6 km
intermediate depth
Location
-15.6790°N
-174.9149°E

Technical Information

Event ID
us6000k4h3
Event Type
earthquake
Status
✓ Reviewed
Significance
271
Stations Used
20
Azimuthal Gap
56.0°
Min Station Distance
3.080°
RMS Residual
0.60 sec
Last Updated
2023-06-17 21:36:53 UTC

Common Questions

How strong was the magnitude 4.2 earthquake near Hihifo, Tonga?

The magnitude 4.2 earthquake that struck 123 km WNW of Hihifo, Tonga on April 9, 2023 at 22:18 UTC had a depth of 268.6 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 4.2 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.2 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000k4h3). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, April 9, 2023). M4.2 Earthquake 123 km WNW of Hihifo, TongaApril 9, 2023. Retrieved June 17, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000k4h3/