M5.5 earthquake 119 km W of Neiafu, Vavau, Tonga
A magnitude 5.5 earthquake struck 119 km W of Neiafu, Vavau, Tonga at 17:38 local time (04:38 UTC) on 12 Oct 2026, at a depth of 180 km, according to USGS, GFZ and INGV.
Reported by 3 agencies · revised from M5.8 · 1 reports to USGS “Did You Feel It?”
Data: USGS, GFZ, INGV · updated 2026-10-29 22:53 UTC · reviewed
- Magnitude
- 5.5moderate
moment magnitude (W phase) (mww)
revised from 5.8 - Depth
- 179.9 km
- Status
- Reviewed
- Origin time
- 2026-10-12 04:38:11 UTC
- Local: 12 Oct 2026, 17:38:11 (Pacific/Tongatapu)
- Epicentre
- 18.575° S, 175.110° W
Circles show this event and others within 71 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map
Nearby places
| Place | Distance | Est. shaking |
|---|---|---|
| NeiafuVavau, Tonga · pop. 3,825 | 119 km | IIIWeak |
Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 124 km.
Every agency's solution
Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS, which has been reviewed by an analyst.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| GFZGFZ via GEOFON, GFZ Helmholtz Centre for Geosciences | 5.5 Mwwas 5.5 | 176.3 km | 18.66° S, 175.15° W | +0.0 s | Automatic · 5 revisions |
| USGSheadlineUSGS NEIC via U.S. Geological Survey | 5.5 mww | 179.9 km | 18.57° S, 175.11° W | – | Reviewed · 2 revisions |
| INGVSURVEY-INGV-A via Istituto Nazionale di Geofisica e Vulcanologia | 5.8 Mwp | 183.6 km | 18.77° S, 174.87° W | +0.3 s | Automatic |
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How big was it?
Felt by most people over a wide area. Can damage poorly built structures close to the epicentre.
It released roughly the energy of 2.7 kt of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 180 km this was a intermediate-depth earthquake, which spreads shaking over a wider area but less intensely.
M5.5 releases about 32× the energy of M4.5, and its waves are about 10× taller on a seismogram. Energy: 2.7 kt of TNT vs 85 t of TNT.
Each square is the energy of one M4.5. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
1 later earthquake within 71 km; the largest was M4.5 13 days ago. 1 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M5.5
1 later earthquake nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 106.47 | 4.5 | 257 |
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Reports close 14 days after an earthquake.
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Event id gfz2026tzgc. First recorded here 12 Oct 2026, 04:45:58 UTC. Solutions: GFZ (geofon:gfz2026tzgc); USGS (usgs:us6000u1pl); INGV (ingv:47513282). Cite as: SeismoAtlas, “M5.5 earthquake 119 km W of Neiafu, Vavau, Tonga”, https://seismoatlas.com/earthquake/gfz2026tzgc-m5-5-earthquake-119-km-w-of-neiafu-vavau-tonga, data from USGS, GFZ, INGV.
JSON: /api/v1/events/gfz2026tzgc. SeismoAtlas is not an official warning service.