Early-est:     Tonga Islands    2025.02.03-10:32:03.84    q:A      mb:4.9    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: 4.9 [26]    Mwp: - [0]    Mwpd: - [0] Region: Tonga Islands Origin Time: 2025.02.03-10:32:03.84 UTC Hypocenter: lat: -20.38°  lon: -174.23°  [+/-12km]    depth: 110km  [+/-15km] Location Quality: qualityCode:  A     stdErr: 1.1s   assocPhases: 70   usedPhases: 24 minDist: 4.3°   maxDist: 154.7°   AzGap: 62°   2ndAzGap: 90°   atten: -2.21 [+/-0.18] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 10km   maxHorUnc: 12km   azMaxHorUnc: 179° 68%ConfEllipsoid:   semiMajorAxisLength: 16km   majorAxisAzimuth: 11°   majorAxisPlunge: 57°   semiIntermediateAxisLength: 13km   intermediateAxisAzimuth: 164°   intermediateAxisPlunge: 30°   semiMinorAxisLength: 12km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.5 [17]    Td: 2.2Xs [1]    Td*T50Ex: - [0]    To: 2.4s [8] Closest plate boundaries:    Tonga / Pacific [subduction zone]: distance: ~90km    Tonga - Niuafo'ou [continental convergent boundary]: distance: ~130km    Tonga - Australia [oceanic transform fault]: distance: ~200km Subduction geometry:    Zone: Kermadec-Tonga    Slab depth at epicenter: 35km 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:        110km        110km        110km Slab depth at epicenter:        35km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 86°   dip: 51°   rake: -5° Nodal Plane 2: strike: 179°   dip: 86°   rake: -141° Quality: azimuthalGap: -1°   stationPolarityCount: 23   misfitWeightCount: 8.5   misfit: 0.08   stationDistributionRatio: 0.50   meanDistP: 21.8   meanDistT: 42.7   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH): Nodal Plane 1: strike: 184°   dip: 76°   rake: -153° Nodal Plane 2: strike: 87°   dip: 64°   rake: -16° Quality: azimuthalGap: 62°   stationPolarityCount: 24   misfit: 0.14   stationDistributionRatio: 0.59   rmsAngDiffAccPref: 12.20   fracAcc30degPref: 1.00   qualityCode: B 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: 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
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

Event ID: smi:KOERI/ee/event/1738578723210
Event info last updated: 2025.02.03-11:32:49 UTC
Event first association/location: 2025.02.03-10:37:05 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI