M5.5 earthquake 75 km NNW of Port-Olry, Vanuatu
A magnitude 5.5 earthquake struck 75 km NNW of Port-Olry, Vanuatu on Mon, Feb 24, 1986, 5:28 AM GMT+11 (18:28 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M6.5 78 km W of Sola, Vanuatu. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.5 (Mw, moment), moderate
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1986-02-23 18:28:52 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 14.449° S, 166.722° E
- Region
- Vanuatu
- Strongest shaking
- IV, light shaking
- 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 |
|---|---|---|---|
| 5.5 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 5.44 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 5.4 | 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, 30C Centroid Location: Origin Time 18:28:56.7 0.5 Lat 14.54S 0.04 Lon 166.40E 0.04 Dep 48.9 2.6 Half-duration 1.9 Moment Tensor; Scale 10**24 D-CM Mrr=1.50 0.05 Mtt=0.49 0.09 Mff=-1.99 0.09 Mrt=0.22 0.07 Mrf=0.04 0.08 Mtf=-0.36 0.06 Principal Axes: (T) Val=1.54 Plg=78 Azm=3 (N) Val=0.50 Plg=12 Azm=189 (P) Val=-2.04 Plg=1 Azm=98 Best Double Couple:Mo=1.8*10**24 NP1:Strike=176 Dip=45 Slip=73 NP2:Strike=20 Dip=47 Slip=107
From the USGS event page for usp0002r8a. U.S. Geological Survey text and figures are in the public domain.
Shaking
The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.
- Strongest estimated
- IV, light shaking
- Peak ground acceleration
- 4.1% of gravity
- Peak ground velocity
- 1.0 cm/s
- Map
- Automatic
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 2.5 and up: 4 in the 60 days after this one and 3 in the 30 days before it.
After
- 3.913 km WNW of Port-Olry, Vanuatu · 14803 days ago · 33 km deep · 65 km away
- 5.251 km SSW of Sola, Vanuatu · 14799 days ago · 202 km deep · 65 km away
- 6.578 km W of Sola, Vanuatu · 14781 days ago · 29 km deep · 60 km away
- 4.823 km NE of Port-Olry, Vanuatu · 14778 days ago · 169 km deep · 77 km away
Before
Earthquakes todayVanuatu earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0002r8a (also filed as gcmtb022386a, gcmt19860223182852, iscgem504351). Read Thu, Oct 1, 2026, 7:38 PM UTC.