Early-est:     Off East Coast of Honshu, Japan    2025.11.09-22:04:17.89    q:B      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 [34]    Mwp: 5.2X [2]    Mwpd: - [0] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.09-22:04:17.89 UTC Hypocenter: lat: 39.28°  lon: 143.52°  [+/-14km]    depth: 10km  [+/-14km] Location Quality: qualityCode:  B     stdErr: 1.0s   assocPhases: 73   usedPhases: 41 minDist: 2.4°   maxDist: 151.6°   AzGap: 97°   2ndAzGap: 147°   atten: -0.96 [+/-0.20] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 11km   maxHorUnc: 14km   azMaxHorUnc: 92° 68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 94°   majorAxisPlunge: 9°   semiIntermediateAxisLength: 15km   intermediateAxisAzimuth: 193°   intermediateAxisPlunge: 46°   semiMinorAxisLength: 13km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.4 [29]    Td: 2.3Xs [2]    Td*T50Ex: - [0]    To: 18.3s [21] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~60km    Okhotsk / Pacific [subduction zone]: distance: ~190km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 13km 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:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        13km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 117°   dip: 13°   rake: 24° Nodal Plane 2: strike: 4°   dip: 85°   rake: 102° Quality: azimuthalGap: -1°   stationPolarityCount: 41   misfitWeightCount: 6.6   misfit: 0.10   stationDistributionRatio: 0.60   meanDistP: 33.9   meanDistT: 32.4   qualityCode: C 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: 224°   dip: 66°   rake: -146° Nodal Plane 2: strike: 119°   dip: 60°   rake: -28° Quality: azimuthalGap: 97°   stationPolarityCount: 41   misfit: 0.30   stationDistributionRatio: 0.61   rmsAngDiffAccPref: 32.91   fracAcc30degPref: 0.73   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/1762725858540
Event info last updated: 2025.11.09-23:02:26 UTC
Event first association/location: 2025.11.09-22:13:19 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI