Early-est:     Off East Coast of Honshu, Japan    2025.11.12-19:08:54.81    q:B      mb:4.7    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: 4.7 [12]    Mwp: - [0]    Mwpd: - [0] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.12-19:08:54.81 UTC Hypocenter: lat: 39.21°  lon: 143.96°  [+/-14km]    depth: 18km  [+/-13km] Location Quality: qualityCode:  B     stdErr: 0.9s   assocPhases: 49   usedPhases: 16 minDist: 2.9°   maxDist: 143.5°   AzGap: 178°   2ndAzGap: 202°   atten: -0.99 [+/-0.35] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 14km   azMaxHorUnc: 119° 68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 120°   majorAxisPlunge: 2°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 210°   intermediateAxisPlunge: 1°   semiMinorAxisLength: 13km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.4 [12]    Td: 0.7Xs [1]    Td*T50Ex: - [0]    To: 10.5s [8] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~20km    Okhotsk / Pacific [subduction zone]: distance: ~190km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 9km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (20km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        18km        18km        18km Slab depth at epicenter:        9km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 146°   dip: 9°   rake: -129° Nodal Plane 2: strike: 5°   dip: 83°   rake: -85° Quality: azimuthalGap: -1°   stationPolarityCount: 16   misfitWeightCount: 5.5   misfit: 0.09   stationDistributionRatio: 0.39   meanDistP: 36.5   meanDistT: 45.4   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
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: 204°   stationPolarityCount: 16   misfit: 0.99   stationDistributionRatio: 0.00   rmsAngDiffAccPref: 0.00   fracAcc30degPref: 0.00   qualityCode: E 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/1762974534794
Event info last updated: 2025.11.12-20:09:18 UTC
Event first association/location: 2025.11.12-19:45:50 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI