M7.1 earthquake 69 km SSW of Port-Vila, Vanuatu
A magnitude 7.1 earthquake struck 69 km SSW of Port-Vila, Vanuatu on Tue, Mar 6, 1990, 4:38 AM GMT+12 (16:38 UTC), 21 km (13 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 7.1 (Mw, moment), major
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1990-03-05 16:38:12 UTC
- Depth
- 20.7 km (12.9 mi), shallow
- Epicenter
- 18.318° S, 168.063° E
- Region
- Vanuatu
- Strongest shaking
- VI, strong 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 |
|---|---|---|---|
| 7.1 | Mw, moment | USGS National Earthquake Information Center | Preferred · Reviewed |
| 6.96 | Mw, moment | ISC-GEM global catalog | Final · ±0.1 |
| 7.0 | Mwc, centroid moment | Global CMT project | Preliminary |
| 6.48 | Me, energy | Choy, USGS energy magnitude | Reviewed |
| 7.0 | Mww, W-phase moment | Duputel, W-phase inversion | Preliminary |
What happened
The USGS’s account of the effects of this earthquake.
Felt (V) at Port Vila. Depth from broadband displacement seismograms. FAULT PLANE SOLUTION: P-Waves NP1:Strike=155 Dip=70 Slip=45 NP2:Strike=46 Dip=48 Slip=153 Principal Axes: (T) Plg=45 Azm=20 (P) Plg=13 Azm=276 Comment: The focal mechanism is poorly controlled and corresponds to reverse faulting with a large strike-slip component. The preferred fault plane is not determined. RADIATED ENERGY No. of sta: 8 Focal mech. C Energy 1.3+0.3*10**14 Nm MOMENT TENSOR SOLUTION Dep 22 No. of sta: 16 Moment Tensor; Scale 10**19 Nm Mrr=0.95 Mtt=3.74 Mff=-4.69 Mrt=2.05 Mrf=-0.75 Mtf=-2.21 Principal axes: (T) Val=5.35 Plg=26 Azm=14 (N) Val=-0.11 Plg=64 Azm=189 (P) Val=-5.25 Plg=2 Azm=283 Best Double Couple:Mo=5.3*10**19 NP1:Strike=56 Dip=70 Slip=162 NP2:Strike=152 Dip=73 Slip=21 CENTROID, MOMENT TENSOR (HRV) Data Used: GDSN L.P.B.: 17S, 49C M.W.: 11S, 29C Centroid Location: Origin Time 16:38:21.8 0.2 Lat 18.35S 0.01 Lon 168.04E 0.01 Dep 36.9 0.7 Half-duration 9.0 Moment Tensor; Scale 10**19 Nm Mrr=2.76 0.03 Mtt=-0.32 0.02 Mff=-2.43 0.03 Mrt=1.07 0.07 Mrf=-1.65 0.07 Mtf=0.77 0.02 Principal Axes: (T) Val=3.42 Plg=71 Azm=47 (N) Val=-0.13 Plg=7 Azm=157 (P) Val=-3.29 Plg=18 Azm=249 Best Double Couple:Mo=3.3*10**19 NP1:Strike=350 Dip=28 Slip=104 NP2:Strike=153 Dip=63 Slip=83
From the USGS event page for usp000467e. 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
- VI, strong shaking
- Peak ground acceleration
- 11.6% of gravity
- Peak ground velocity
- 2.6 cm/s
- Map
- Automatic
Did you feel it?
No one has reported feeling this quake to the USGS.
Fault motion and ground failure
How the rock slipped, from the moment tensor, and the USGS estimate of landslides and liquefaction.
- Faulting
- Reverse (thrust)
- Moment magnitude
- 7.0 Mww
- Nodal plane 1
- Strike 337°, dip 21°, rake 80°
- Nodal plane 2
- Strike 167°, dip 69°, rake 93°
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 4.1 and up: 12 in the 60 days after this one and 1 in the 30 days before it.
After
- 4.755 km SSW of Port-Vila, Vanuatu · 13359 days ago · 33 km deep · 14 km away
- 5.475 km SSW of Port-Vila, Vanuatu · 13359 days ago · 34 km deep · 7 km away
- 4.458 km SSW of Port-Vila, Vanuatu · 13359 days ago · 45 km deep · 14 km away
- 4.482 km SSW of Port-Vila, Vanuatu · 13359 days ago · 10 km deep · 13 km away
- 4.950 km SSW of Port-Vila, Vanuatu · 13358 days ago · 33 km deep · 22 km away
- 4.9Vanuatu · 13358 days ago · 33 km deep · 37 km away
- 5.285 km SSW of Port-Vila, Vanuatu · 13356 days ago · 17 km deep · 17 km away
- 4.683 km SSW of Port-Vila, Vanuatu · 13339 days ago · 33 km deep · 17 km away
- 4.684 km SSW of Port-Vila, Vanuatu · 13335 days ago · 33 km deep · 15 km away
- 4.680 km S of Port-Vila, Vanuatu · 13327 days ago · 41 km deep · 24 km away
- 5.539 km SSW of Port-Vila, Vanuatu · 13326 days ago · 36 km deep · 31 km away
- 4.878 km S of Port-Vila, Vanuatu · 13309 days ago · 56 km deep · 34 km away
Before
Earthquakes todayVanuatu earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp000467e (also filed as choy19900305163812, gcmtc030590a, gcmt19900305163815, duputel030590a, atlas19900305163814, iscgem374735). Read Thu, Oct 1, 2026, 12:40 PM UTC.