M5.1 earthquake 104 km NE of Neiafu, Tonga
A magnitude 5.1 earthquake struck 104 km NE of Neiafu, Tonga on Sat, Jul 26, 1986, 8:07 AM GMT-12 (20:07 UTC), 33 km (21 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.1 (Mw, moment), moderate
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1986-07-26 20:07:02 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 18.066° S, 173.202° 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 |
|---|---|---|---|
| 5.1 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 5.07 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 5.1 | 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.: 7S, 11C Centroid Location: Origin Time 20:07: 6.7 1.9 Lat 17.44S 0.55 Lon 172.98W 0.34 Dep 15.0 FIX Half-duration 1.5 Moment Tensor; Scale 10**23 D-CM Mrr=-1.14 1.62 Mtt=5.01 1.68 Mff=-3.88 0.65 Mrt=0.20 1.76 Mrf=-1.45 2.94 Mtf=1.51 1.39 Principal Axes: (T) Val=5.26 Plg=0 Azm=171 (N) Val=-0.54 Plg=68 Azm=81 (P) Val=-4.73 Plg=22 Azm=261 Best Double Couple:Mo=5.0*10**23 NP1:Strike=303 Dip=74 Slip=-16 NP2:Strike=38 Dip=74 Slip=-164
From the USGS event page for usp0002wjj. 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
- OPERATOR_ASSIGNED
Nearby
Within 100 km, magnitude 2.1 and up: 7 in the 60 days after this one and 1 in the 30 days before it.
After
- 5.0143 km E of Neiafu, Tonga · 14680 days ago · 33 km deep · 93 km away
- 5.0130 km ENE of Neiafu, Tonga · 14680 days ago · 33 km deep · 48 km away
- 4.6133 km E of Neiafu, Tonga · 14680 days ago · 33 km deep · 66 km away
- 4.9126 km ENE of Neiafu, Tonga · 14680 days ago · 33 km deep · 32 km away
- 4.9118 km N of Neiafu, Tonga · 14645 days ago · 33 km deep · 88 km away
- 4.894 km ESE of Neiafu, Tonga · 14624 days ago · 33 km deep · 85 km away
- 4.793 km ESE of Neiafu, Tonga · 14622 days ago · 33 km deep · 88 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0002wjj (also filed as gcmtb072686a, gcmt19860726200703, iscgem491775). Read Mon, Oct 5, 2026, 8:11 AM UTC.