M5.6 earthquake 299 km SW of Vaini, Tonga
A magnitude 5.6 earthquake struck 299 km SW of Vaini, Tonga on Thu, Jan 14, 1988, 4:38 AM GMT+13 (15:38 UTC), 109 km (68 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.6 (Mw, moment), moderate
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1988-01-13 15:38:15 UTC
- Depth
- 109.1 km (67.8 mi), intermediate-depth
- Epicenter
- 23.275° S, 177.033° W
- Region
- Tonga
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Magnitude estimates
Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.
| Mag. | Scale | Computed by | Notes |
|---|---|---|---|
| 5.6 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 5.55 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 5.5 | Mwc, centroid moment | Global CMT project | Preliminary |
What happened
The USGS’s account of the effects of this earthquake.
CENTROID, MOMENT TENSOR (HRV) Data Used: GDSN L.P.B.: 13S, 25C Centroid Location: Origin Time 15:38:24.9 0.5 Lat 23.25S 0.05 Lon 176.63W 0.04 Dep 142.7 1.4 Half-duration 2.3 Moment Tensor; Scale 10**17 Nm Mrr=-0.42 0.08 Mtt=0.28 0.12 Mff=0.14 0.12 Mrt=-1.29 0.08 Mrf=-2.19 0.09 Mtf=0.68 0.13 Principal Axes: (T) Val=2.82 Plg=38 Azm=128 (N) Val=-0.36 Plg=9 Azm=31 (P) Val=-2.47 Plg=51 Azm=290 Best Double Couple:Mo=2.6*10**17 NP1:Strike=263 Dip=11 Slip=-37 NP2:Strike=30 Dip=84 Slip=-99
From the USGS event page for usp0003c18. U.S. Geological Survey text and figures are in the public domain.
Did you feel it?
No one has reported feeling this quake to the USGS.
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.6 and up: 2 in the 60 days after this one and 1 in the 30 days before it.
After
- 5.3south of the Fiji Islands · 14134 days ago · 202 km deep · 49 km away
- 5.5south of the Fiji Islands · 14087 days ago · 266 km deep · 90 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0003c18 (also filed as gcmtb011388g, gcmt19880113153824, iscgem447828). Read Mon, Oct 5, 2026, 1:34 AM UTC.