Early-est:     Fiji Islands Region    2026.10.09-08:11:48.26    q:B      mb:4.3    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1791533508120.mech.fmamp_polarity.thumb.jpg     hash:./hypo.1791533508120.mech.hash.thumb.jpg     fmamp_amp_aref:./hypo.1791533508120.mech.fmamp_amp_aref.thumb.jpg     fmamp_amp_mwp:./hypo.1791533508120.mech.fmamp_amp_mwp.thumb.jpg

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

Earthquake Details:
Magnitude: mb: 4.3 [19]    Mwp: 5.9X [1]    Mwpd: 6.0Xinv [1]
Region: Fiji Islands Region
Origin Time: 2026.10.09-08:11:48.26 UTC
Hypocenter: lat: -17.61°  lon: -178.37°  [+/-16km]    depth: 555km  [+/-18km]
Location Quality: qualityCode:  B     stdErr: 0.8s   assocPhases: 42   usedPhases: 25
minDist: 3.4°   maxDist: 150.2°   AzGap: 129°   2ndAzGap: 226°   atten: -1.31 [+/-0.36]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 16km   azMaxHorUnc: 148°
68%ConfEllipsoid:   semiMajorAxisLength: 21km   majorAxisAzimuth: 127°   majorAxisPlunge: 38°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 7°   intermediateAxisPlunge: 32°   semiMinorAxisLength: 14km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.0 [11]    Td: 1.4Xs [1]    Td*T50Ex: - [0]    To: 1.0s [8]
Closest plate boundaries:
   Niuafo'ou - Australia [continental transform fault]: distance: ~170km
Subduction geometry:    Zone: Kermadec-Tonga    Slab depth at epicenter: 550km
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 no
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       555km
       555km
       555km
Slab depth at epicenter:
       550km
       -
       -
./hypo.1791533508120.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 21°   dip: 33°   rake: 21°
Nodal Plane 2: strike: 273°   dip: 79°   rake: 121°
Quality: azimuthalGap: -1°   stationPolarityCount: 21   misfitWeightCount: 5.1   misfit: 0.15   stationDistributionRatio: 0.67   meanDistP: 31.5   meanDistT: 46.4   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1791533508120.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (HASH):    (No solution available)
Nodal Plane 1: strike: 999°   dip: 99°   rake: 999°
Nodal Plane 2: strike: 324°   dip: 13°   rake: 135°
Quality: azimuthalGap: 178°   stationPolarityCount: 22   misfit: 0.99   stationDistributionRatio: 0.54   rmsAngDiffAccPref: 39.19   fracAcc30degPref: 0.00   qualityCode: E
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1791533508120.mech.hash.mechanism.jpg
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (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/_amp_aref
./hypo.1791533508120.mech.fmamp_amp_aref.mechanism.jpg
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (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/_amp_mwp
./hypo.1791533508120.mech.fmamp_amp_mwp.mechanism.jpg

Event ID: smi:KOERI/ee/event/1791533508120
Event info last updated: 2026.10.09-09:12:06 UTC
Event first association/location: 2026.10.09-08:18:02 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI