Early-est:     Fiji Islands Region    2025.12.13-11:46:42.27    q:B      mb:4.4    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1765626402328.mech.fmamp_polarity.thumb.jpg     hash:./hypo.1765626402328.mech.hash.thumb.jpg     fmamp_amp_aref:./hypo.1765626402328.mech.fmamp_amp_aref.thumb.jpg     fmamp_amp_mwp:./hypo.1765626402328.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: 4.4 [34]    Mwp: - [0]    Mwpd: - [0]
Region: Fiji Islands Region
Origin Time: 2025.12.13-11:46:42.27 UTC
Hypocenter: lat: -18.08°  lon: -178.74°  [+/-19km]    depth: 534km  [+/-18km]
Location Quality: qualityCode:  B     stdErr: 1.3s   assocPhases: 107   usedPhases: 66
minDist: 3.1°   maxDist: 153.2°   AzGap: 75°   2ndAzGap: 114°   atten: -0.98 [+/-0.23]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 19km   azMaxHorUnc: 6°
68%ConfEllipsoid:   semiMajorAxisLength: 24km   majorAxisAzimuth: 5°   majorAxisPlunge: 13°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 262°   intermediateAxisPlunge: 44°   semiMinorAxisLength: 17km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.2 [10]    Td: -s [0]    Td*T50Ex: - [0]    To: 1.1s [10]
Closest plate boundaries:
Subduction geometry:    Zone: Kermadec-Tonga    Slab depth at epicenter: 568km
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:
       534km
       534km
       534km
Slab depth at epicenter:
       568km
       -
       -
./hypo.1765626402328.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):
Nodal Plane 1: strike: 3°   dip: 19°   rake: -5°
Nodal Plane 2: strike: 98°   dip: 88°   rake: -109°
Quality: azimuthalGap: -1°   stationPolarityCount: 73   misfitWeightCount: 19.5   misfit: 0.22   stationDistributionRatio: 0.58   meanDistP: 24.9   meanDistT: 23.4   qualityCode: B
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1765626402328.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 249°   dip: 49°   rake: 164°
Nodal Plane 2: strike: 350°   dip: 78°   rake: 43°
Quality: azimuthalGap: 77°   stationPolarityCount: 73   misfit: 0.39   stationDistributionRatio: 0.50   rmsAngDiffAccPref: 27.30   fracAcc30degPref: 0.79   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1765626402328.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.1765626402328.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.1765626402328.mech.fmamp_amp_mwp.mechanism.jpg

Event ID: smi:KOERI/ee/event/1765626402328
Event info last updated: 2025.12.13-12:47:09 UTC
Event first association/location: 2025.12.13-11:52:25 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI