7.6

M7.6 Earthquake 82 km WNW of Hihifo, TongaMay 10, 2023

2023-05-10 16:02:00 UTC (2023-05-10) · approx. 4:02 AM UTC-12 local

Felt by 26 people across nearby locations. Maximum shaking intensity MMI 6.0 (strong).

MagnitudeM7.6(mww)
Time16:02 UTC4:02 AM UTC-12
Depth210.0 kmintermediate depth
Coordinates-15.628°, -174.493°
Felt by26DYFI responses· max MMI 6.0
Status✓ Reviewed by USGS· Tsunami evaluation· green PAGER
green Alertno significant casualties or damage expected
Tsunami Warning Issued

On May 10, 2023 at 16:02 UTC, a magnitude 7.6 intermediate depth earthquake struck 82 km WNW of Hihifo, Tonga, at a depth of 210.0 km and coordinates -15.6278°, -174.4925°. The earthquake was reported felt by 26 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 6.0 (strong). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 380 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 910, making it one of the more significant events of the week. The nearest populated place is Hihifo (population 815).

Physical scale: An earthquake of magnitude 7.6 releases seismic energy equivalent to roughly 3.8 megatons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 106 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

Nearest Populated Places

Hihifopop. 815
MMI 6.0 (strong)
Gataivaipop. 1,141
MMI 4.4 (moderate)
Asaupop. 6,643
MMI 4.4 (moderate)
Vailoapop. 769
MMI 4.4 (moderate)
Mata-Utupop. 1,200
MMI 4.4 (moderate)
Leulumoegapop. 1,458
MMI 4.4 (moderate)
Map showing earthquake epicenter at -15.63°, -174.49°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M7.6 earthquake near 82 km WNW of Hihifo, Tonga

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 26 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M7.6 earthquake near 82 km WNW of Hihifo, Tonga

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Population exposure (USGS PAGER)

Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.

Shaking intensity (MMI)DescriptionPopulation exposed
MMI 3weak233
MMI 4light278,430
MMI 5moderate4,375
MMI 6strong521

Earthquake Details

Magnitude
7.6 mww
Depth
210.0 km
intermediate depth
Location
-15.6278°N
-174.4925°E
Felt Reports
26
DYFI responses
Intensity (MMI)
6.0
strong
Community Intensity
8.1
CDI from reports

Technical Information

Event ID
us6000kawn
Event Type
earthquake
Status
✓ Reviewed
Significance
910
Stations Used
380
Azimuthal Gap
15.0°
Min Station Distance
3.744°
RMS Residual
0.70 sec
Last Updated
2023-07-22 19:16:37 UTC

Common Questions

How strong was the magnitude 7.6 earthquake near Hihifo, Tonga?

The magnitude 7.6 earthquake that struck 82 km WNW of Hihifo, Tonga on May 10, 2023 at 16:02 UTC had a depth of 210.0 km. It was felt by 26 people with maximum shaking intensity of MMI 6.0 (strong). For context, this was a strong earthquake capable of causing significant damage.

Where did the earthquake occur?

The earthquake epicenter was located at -15.6278°, -174.4925°, which is 82 km WNW of Hihifo, Tonga. The nearest populated place is Hihifo (population 815). View all earthquakes in Tonga.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 7.6 earthquakes can continue for months to years 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 7.6 event is within one magnitude unit of that historical record.

Authoritative source: USGS event page (event ID: us6000kawn). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, May 10, 2023). M7.6 Earthquake 82 km WNW of Hihifo, TongaMay 10, 2023. Retrieved July 22, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000kawn/