M5.7 earthquake 79 km N of Hihifo, Tonga
A magnitude 5.7 earthquake struck 79 km N of Hihifo, Tonga on Thu, May 19, 1988, 10:17 PM GMT-11 (09:17 UTC), 101 km (62 mi) below the surface.
A larger quake followed: M6.3 111 km NNE of Hihifo, Tonga. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.7 (Mw, moment), moderate
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1988-05-20 09:17:27 UTC
- Depth
- 100.5 km (62.4 mi), intermediate-depth
- Epicenter
- 15.241° S, 173.892° 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 |
|---|---|---|---|
| 5.7 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 5.67 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 5.7 | 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.: 14S, 34C Centroid Location: Origin Time 09:17:33.5 0.5 Lat 14.75S 0.05 Lon 173.97W 0.05 Dep 90.1 2.8 Half-duration 2.6 Moment Tensor; Scale 10**17 Nm Mrr=-0.14 0.10 Mtt=2.44 0.15 Mff=-2.30 0.17 Mrt=-2.35 0.08 Mrf=-1.99 0.08 Mtf=-0.56 0.14 Principal Axes: (T) Val=3.88 Plg=33 Azm=173 (N) Val=0.09 Plg=38 Azm=53 (P) Val=-3.97 Plg=35 Azm=290 Best Double Couple:Mo=3.9*10**17 NP1:Strike=320 Dip=38 Slip=-2 NP2:Strike=52 Dip=89 Slip=-128
From the USGS event page for usp0003g4f. 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.
How well it is located
Reviewed by a seismologist.
- Depth from
- CONSTRAINED_BY_DEPTH_PHASES
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.7 and up: 1 in the 60 days after this one and 0 in the 30 days before it.
After
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0003g4f (also filed as gcmtb052088b, gcmt19880520091726, iscgem438313). Read Sun, Oct 4, 2026, 8:56 PM UTC.