4.6

M4.6 Earthquake 107 km NW of Nuku‘alofa, TongaJuly 11, 2022

2022-07-11 20:09:02 UTC (2022-07-11) · approx. 8:09 AM UTC-12 local

MagnitudeM4.6(mb)
Time20:09 UTC8:09 AM UTC-12
Depth187.8 kmintermediate depth
Coordinates-20.372°, -175.833°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 11, 2022 at 20:09 UTC, a magnitude 4.6 intermediate depth earthquake struck 107 km NW of Nuku‘alofa, Tonga, at a depth of 187.8 km and coordinates -20.3720°, -175.8333°. This earthquake was detected by 29 seismic stations with good location accuracy and was assigned a USGS significance rating of 326, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.6 releases seismic energy equivalent to roughly 120 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 899 m — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Tonga, a region characterized by the Tonga-Kermadec subduction zone, where the Pacific Plate descends at up to 240 mm per year — the fastest plate convergence on Earth. The nearest mapped fault system is the Tonga Trench. View all earthquakes in Tonga.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at -20.37°, -175.83°

Earthquake Details

Magnitude
4.6 mb
Depth
187.8 km
intermediate depth
Location
-20.3720°N
-175.8333°E

Technical Information

Event ID
us6000i3nz
Event Type
earthquake
Status
✓ Reviewed
Significance
326
Stations Used
29
Azimuthal Gap
148.0°
Min Station Distance
7.503°
RMS Residual
0.52 sec
Last Updated
2022-09-24 21:25:55 UTC

Common Questions

How strong was the magnitude 4.6 earthquake near Nuku‘alofa, Tonga?

The magnitude 4.6 earthquake that struck 107 km NW of Nuku‘alofa, Tonga on July 11, 2022 at 20:09 UTC had a depth of 187.8 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at -20.3720°, -175.8333°, which is 107 km NW of Nuku‘alofa, Tonga. View all earthquakes in Tonga.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.6 earthquakes can continue for several days and gradually diminish over time.

Has Tonga had earthquakes this big before?

The largest recorded earthquake in Tonga was the M8.1 Tonga Trench earthquake of June 26, 1917. Today's magnitude 4.6 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000i3nz). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, July 11, 2022). M4.6 Earthquake 107 km NW of Nuku‘alofa, TongaJuly 11, 2022. Retrieved September 24, 2022 from https://www.earthquaketracker.org/earthquakes/event/us6000i3nz/