M5.3 earthquake 82 km ESE of Pangai, Tonga
A magnitude 5.3 earthquake struck 82 km ESE of Pangai, Tonga on Fri, Oct 23, 1987, 2:10 AM GMT+13 (13:10 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
- 5.3 (Mw, moment), moderate
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1987-10-22 13:10:33 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 20.131° S, 173.639° 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 |
|---|---|---|---|
| 5.3 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 5.26 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 5.3 | 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.: 15S, 26C Centroid Location: Origin Time 13:10:27.4 1.9 Lat 19.87S 0.12 Lon 174.23W 0.18 Dep 15.0 FIX Half-duration 1.7 Moment Tensor; Scale 10**16 Nm Mrr=-2.21 0.40 Mtt=-0.76 0.46 Mff=2.97 0.52 Mrt=4.90 0.92 Mrf=8.08 1.27 Mtf=1.83 0.41 Principal Axes: (T) Val=10.61 Plg=36 Azm=297 (N) Val=-1.39 Plg=5 Azm=31 (P) Val=-9.22 Plg=53 Azm=127 Best Double Couple:Mo=9.9*10**16 NP1:Strike=2 Dip=10 Slip=-119 NP2:Strike=212 Dip=82 Slip=-85
From the USGS event page for usp00039ge. 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
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.3 and up: 3 in the 60 days after this one and 1 in the 30 days before it.
After
- 4.473 km E of Pangai, Tonga · 14216 days ago · 33 km deep · 23 km away
- 4.6117 km SSE of Pangai, Tonga · 14169 days ago · 33 km deep · 65 km away
- 4.9131 km ENE of ‘Ohonua, Tonga · 14165 days ago · 33 km deep · 90 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp00039ge (also filed as gcmtb102287e, gcmt19871022131033, iscgem455939). Read Thu, Oct 1, 2026, 6:18 AM UTC.