Early-est:     Vanuatu Islands    2026.08.16-03:20:23.17    q:A      mb:5.4    Mwp:6.1*    Mwpd:-    Td*T50Ex:1.3     fmamp_polarity:./hypo.1786850425909.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1786850425909.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1786850425909.mech.hash.thumb.jpg

Automatic solution - this event has not been reviewed by a seismologist
Automatically determined event information may be incorrect!

Earthquake Details:
Magnitude: mb: 5.4 [81]    Mwp: 6.1* [50]    Mwpd: 6.1Xinv [48]
Region: Vanuatu Islands
Origin Time: 2026.08.16-03:20:23.17 UTC
Hypocenter: lat: -14.58°  lon: 167.25°  [+/-14km]    depth: 165km  [+/-18km]
Location Quality: qualityCode:  A     stdErr: 1.1s   assocPhases: 278   usedPhases: 149
minDist: 6.6°   maxDist: 168.9°   AzGap: 27°   2ndAzGap: 52°   atten: -1.26 [+/-0.17]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 11km   maxHorUnc: 14km   azMaxHorUnc: 89°
68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 113°   majorAxisPlunge: 65°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 263°   intermediateAxisPlunge: 22°   semiMinorAxisLength: 14km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.5 [69]    Td: 2.8s [27]    Td*T50Ex: 1.3 [27]    To: 3.5s [69]
Closest plate boundaries:
   New Hebrides - Pacific [continental convergent boundary]: distance: ~100km
   New Hebrides / Australia [subduction zone]: distance: ~110km
   Pacific / Australia [subduction zone]: distance: ~150km
Subduction geometry:    Zone: Santa Cruz Islands/Vanuatu/Loyalty Islands: DEBUG: error: [Errno 2] No such file or directory: 'gmt'    Slab depth at epicenter: error: evaluating slab depth: -999.9
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 YES (110km)
 YES (100km)
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   1.3
   1.3
   1.3
Td*To:
     9.8
     9.8
     9.8
Mwp magnitude:
       6.1*
       6.1*
       6.1*
Hypocenter depth:
       165km
       165km
       165km
Slab depth at epicenter:
       n/a
       -
       -
Tsunami and Rupture predictions (TEST!): No prediction: Event too small (Mwp<7.0) or too few Mwp readings (N<20)
./hypo.1786850425909.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):
Nodal Plane 1: strike: 59°   dip: 36°   rake: 87°
Nodal Plane 2: strike: 243°   dip: 54°   rake: 92°
Quality: azimuthalGap: -1°   stationPolarityCount: 72   misfitWeightCount: 20.9   misfit: 0.14   stationDistributionRatio: 0.67   meanDistP: 28.7   meanDistT: 19.9   qualityCode: B
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1786850425909.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 164°   dip: 27°   rake: 77°
Nodal Plane 2: strike: 357°   dip: 64°   rake: 96°
Quality: azimuthalGap: -1°   stationPolarityCount: 22   misfitWeightCount: 8.6   misfit: 0.00   stationDistributionRatio: 0.59   meanDistP: 39.2   meanDistT: 39.1   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity_waveform
./hypo.1786850425909.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 193°   dip: 33°   rake: 105°
Nodal Plane 2: strike: 355°   dip: 58°   rake: 80°
Quality: azimuthalGap: 52°   stationPolarityCount: 72   misfit: 0.14   stationDistributionRatio: 0.61   rmsAngDiffAccPref: 34.78   fracAcc30degPref: 0.58   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1786850425909.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1786850425909
Event info last updated: 2026.08.16-04:19:01 UTC
Event first association/location: 2026.08.16-03:24:01 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA