Early-est:     Off East Coast of Honshu, Japan    2025.11.08-20:29:16.68    q:A      mb:5.2    Mwp:5.5    Mwpd:-    Td*T50Ex:0.8     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: 5.2 [124]    Mwp: 5.5 [10]    Mwpd: 5.7Xinv [6] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.08-20:29:16.68 UTC Hypocenter: lat: 39.39°  lon: 143.49°  [+/-9km]    depth: 10km  [+/-8km] Location Quality: qualityCode:  A     stdErr: 1.3s   assocPhases: 156   usedPhases: 140 minDist: 2.3°   maxDist: 146.4°   AzGap: 99°   2ndAzGap: 102°   atten: -1.12 [+/-0.16] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 7km   maxHorUnc: 9km   azMaxHorUnc: 150° 68%ConfEllipsoid:   semiMajorAxisLength: 11km   majorAxisAzimuth: 150°   majorAxisPlunge: 1°   semiIntermediateAxisLength: 9km   intermediateAxisAzimuth: 241°   intermediateAxisPlunge: 25°   semiMinorAxisLength: 8km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.5 [112]    Td: 1.7s [9]    Td*T50Ex: 0.8 [9]    To: 24.9s [98] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~60km    Okhotsk / Pacific [subduction zone]: distance: ~180km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 14km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (60km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    0.8    0.8    0.8 Td*To:      42.3      42.3      42.3 Mwp magnitude:        5.5        5.5        5.5 Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        14km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 235°   dip: 84°   rake: 5° Nodal Plane 2: strike: 145°   dip: 85°   rake: 174° Quality: azimuthalGap: -1°   stationPolarityCount: 120   misfitWeightCount: 16.5   misfit: 0.20   stationDistributionRatio: 0.29   meanDistP: 39.5   meanDistT: 58.2   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 146°   dip: 89°   rake: 170° Nodal Plane 2: strike: 236°   dip: 80°   rake: 1° Quality: azimuthalGap: 101°   stationPolarityCount: 120   misfit: 0.44   stationDistributionRatio: 0.64   rmsAngDiffAccPref: 34.19   fracAcc30degPref: 0.71   qualityCode: C 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/1762633754600
Event info last updated: 2025.11.08-21:30:30 UTC
Event first association/location: 2025.11.08-20:34:14 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI