4.6

M4.6 Earthquake 91 km ESE of Hihifo, TongaJuly 19, 2026

2026-07-19 09:48:03 UTC (8 hours ago) · approx. 9:48 PM UTC-12 local

MagnitudeM4.6(mb)
Time09:48 UTC9:48 PM UTC-12
Depth10.0 kmshallow crustal
Coordinates-16.345°, -173.038°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 19, 2026 at 09:48 UTC, a magnitude 4.6 shallow crustal earthquake struck 91 km ESE of Hihifo, Tonga, at a depth of 10.0 km and coordinates -16.3454°, -173.0380°. This earthquake was detected by 34 seismic stations with excellent 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 -16.35°, -173.04°

Earthquake Details

Magnitude
4.6 mb
Depth
10.0 km
shallow crustal
Location
-16.3454°N
-173.0380°E

Technical Information

Event ID
us7000t1rx
Event Type
earthquake
Status
✓ Reviewed
Significance
326
Stations Used
34
Azimuthal Gap
74.0°
Min Station Distance
2.709°
RMS Residual
0.94 sec
Last Updated
2026-07-19 10:42:08 UTC

Common Questions

How strong was the magnitude 4.6 earthquake near Hihifo, Tonga?

The magnitude 4.6 earthquake that struck 91 km ESE of Hihifo, Tonga on July 19, 2026 at 09:48 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 -16.3454°, -173.0380°, which is 91 km ESE of Hihifo, 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: us7000t1rx). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, July 19, 2026). M4.6 Earthquake 91 km ESE of Hihifo, TongaJuly 19, 2026. Retrieved July 19, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000t1rx/