Early-est:     Vanuatu Islands    2026.03.31-10:03:53.11    q:B      mb:4.5*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1774951434360.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1774951434360.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1774951434360.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: 4.5* [12]    Mwp: - [0]    Mwpd: - [0]
Region: Vanuatu Islands
Origin Time: 2026.03.31-10:03:53.11 UTC
Hypocenter: lat: -16.74°  lon: 167.70°  [+/-21km]    depth: 90km  [+/-28km]
Location Quality: qualityCode:  B     stdErr: 0.8s   assocPhases: 18   usedPhases: 16
minDist: 4.7°   maxDist: 145.7°   AzGap: 120°   2ndAzGap: 199°   atten: -2.27 [+/-0.23]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 12km   maxHorUnc: 21km   azMaxHorUnc: 155°
68%ConfEllipsoid:   semiMajorAxisLength: 34km   majorAxisAzimuth: 153°   majorAxisPlunge: 47°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 352°   intermediateAxisPlunge: 41°   semiMinorAxisLength: 15km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.4 [8]    Td: -s [0]    Td*T50Ex: - [0]    To: 2.3s [8]
Closest plate boundaries:
   New Hebrides / Australia [subduction zone]: distance: ~90km
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 (90km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       90km
       90km
       90km
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.1774951434360.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 0°   dip: 42°   rake: -56°
Nodal Plane 2: strike: 138°   dip: 56°   rake: -117°
Quality: azimuthalGap: -1°   stationPolarityCount: 10   misfitWeightCount: 2.6   misfit: 0.05   stationDistributionRatio: 0.27   meanDistP: 51.6   meanDistT: 54.0   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1774951434360.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (No solution available)
Nodal Plane 1: strike: 0°   dip: 0°   rake: 0°
Nodal Plane 2: strike: 270°   dip: 90°   rake: 90°
Quality: azimuthalGap: -1°   stationPolarityCount: 0   misfitWeightCount: -1.0   misfit: -1.00   stationDistributionRatio: -1.00   meanDistP: -1.0   meanDistT: -1.0   qualityCode: X
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity_waveform
./hypo.1774951434360.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 305°   dip: 71°   rake: 159°
Nodal Plane 2: strike: 42°   dip: 70°   rake: 20°
Quality: azimuthalGap: 144°   stationPolarityCount: 10   misfit: 0.49   stationDistributionRatio: 0.37   rmsAngDiffAccPref: 50.25   fracAcc30degPref: 0.27   qualityCode: D
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1774951434360.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1774951434360
Event info last updated: 2026.03.31-11:02:00 UTC
Event first association/location: 2026.03.31-10:10:02 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA