4.9

M4.9 Earthquake 147 km SE of Hihifo, TongaAugust 15, 2022

2022-08-15 22:17:34 UTC (2022-08-15) · approx. 10:17 AM UTC-12 local

MagnitudeM4.9(mb)
Time22:17 UTC10:17 AM UTC-12
Depth10.0 kmshallow crustal
Coordinates-16.795°, -172.722°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 15, 2022 at 22:17 UTC, a magnitude 4.9 shallow crustal earthquake struck 147 km SE of Hihifo, Tonga, at a depth of 10.0 km and coordinates -16.7949°, -172.7220°. This earthquake was detected by 36 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.

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 -16.79°, -172.72°

Earthquake Details

Magnitude
4.9 mb
Depth
10.0 km
shallow crustal
Location
-16.7949°N
-172.7220°E

Technical Information

Event ID
us7000i22u
Event Type
earthquake
Status
✓ Reviewed
Significance
369
Stations Used
36
Azimuthal Gap
70.0°
Min Station Distance
2.210°
RMS Residual
0.57 sec
Last Updated
2022-10-28 02:27:50 UTC

Common Questions

How strong was the magnitude 4.9 earthquake near Hihifo, Tonga?

The magnitude 4.9 earthquake that struck 147 km SE of Hihifo, Tonga on August 15, 2022 at 22:17 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 -16.7949°, -172.7220°, which is 147 km SE of Hihifo, Tonga. View all earthquakes in Tonga.

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.

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 4.9 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000i22u). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, August 15, 2022). M4.9 Earthquake 147 km SE of Hihifo, TongaAugust 15, 2022. Retrieved October 28, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000i22u/