Early-est:     Fiji Islands Region    2026.10.10-12:21:04.58    q:B      mb:4.4    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:     hash:     fmamp_amp_aref:     fmamp_amp_mwp:

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

Earthquake Details: Magnitude: mb: 4.4 [15]    Mwp: - [0]    Mwpd: - [0] Region: Fiji Islands Region Origin Time: 2026.10.10-12:21:04.58 UTC Hypocenter: lat: -19.68°  lon: -177.49°  [+/-20km]    depth: 576km  [+/-16km] Location Quality: qualityCode:  B     stdErr: 0.7s   assocPhases: 43   usedPhases: 21 minDist: 4.6°   maxDist: 149.8°   AzGap: 108°   2ndAzGap: 196°   atten: -1.12 [+/-0.36] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 20km   azMaxHorUnc: 11° 68%ConfEllipsoid:   semiMajorAxisLength: 25km   majorAxisAzimuth: 10°   majorAxisPlunge: 12°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 277°   intermediateAxisPlunge: 15°   semiMinorAxisLength: 15km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.0 [11]    Td: -s [0]    Td*T50Ex: - [0]    To: 0.8s [10] Closest plate boundaries:    Niuafo'ou - Australia [oceanic transform fault]: distance: ~110km    Tonga - Australia [oceanic transform fault]: distance: ~140km    Tonga - Niuafo'ou [continental convergent boundary]: distance: ~160km    Tonga / Pacific [subduction zone]: distance: ~430km Subduction geometry:    Zone: Kermadec-Tonga    Slab depth at epicenter: 449km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (430km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        576km        576km        576km Slab depth at epicenter:        449km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 1°   dip: 14°   rake: -74° Nodal Plane 2: strike: 164°   dip: 77°   rake: -94° Quality: azimuthalGap: -1°   stationPolarityCount: 14   misfitWeightCount: 4.2   misfit: 0.10   stationDistributionRatio: 0.55   meanDistP: 31.7   meanDistT: 39.2   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 64°   dip: 26°   rake: -86° Nodal Plane 2: strike: 240°   dip: 64°   rake: -92° Quality: azimuthalGap: 119°   stationPolarityCount: 14   misfit: 0.35   stationDistributionRatio: 0.51   rmsAngDiffAccPref: 35.37   fracAcc30degPref: 0.62   qualityCode: D Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (No solution available) Nodal Plane 1: strike: 0°   dip: 0°   rake: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (No solution available) Nodal Plane 1: strike: 0°   dip: 0°   rake: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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

Event ID: smi:KOERI/ee/event/1791634864723
Event info last updated: 2026.10.10-13:22:02 UTC
Event first association/location: 2026.10.10-12:27:29 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI