Early-est:     Hokkaido, Japan Region    2025.11.09-04:16:41.87    q:C      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 [16]    Mwp: - [0]    Mwpd: - [0] Region: Hokkaido, Japan Region Origin Time: 2025.11.09-04:16:41.87 UTC Hypocenter: lat: 42.24°  lon: 142.16°  [+/-14km]    depth: 27km  [+/-16km] Location Quality: qualityCode:  C     stdErr: 0.9s   assocPhases: 24   usedPhases: 21 minDist: 0.8°   maxDist: 146.0°   AzGap: 137°   2ndAzGap: 138°   atten: -0.59 [+/-0.17] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 14km   azMaxHorUnc: 78° 68%ConfEllipsoid:   semiMajorAxisLength: 19km   majorAxisAzimuth: 95°   majorAxisPlunge: 41°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 189°   intermediateAxisPlunge: 5°   semiMinorAxisLength: 14km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.7 [7]    Td: -s [0]    Td*T50Ex: - [0]    To: 0.8Xs [3] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~250km    Okhotsk / Pacific [subduction zone]: distance: ~250km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 75km 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:        27km        27km        27km Slab depth at epicenter:        75km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 128°   dip: 25°   rake: -172° Nodal Plane 2: strike: 31°   dip: 87°   rake: -65° Quality: azimuthalGap: -1°   stationPolarityCount: 18   misfitWeightCount: 1.2   misfit: 0.06   stationDistributionRatio: 0.36   meanDistP: 49.1   meanDistT: 53.8   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 85°   dip: 29°   rake: 146° Nodal Plane 2: strike: 205°   dip: 75°   rake: 66° Quality: azimuthalGap: 136°   stationPolarityCount: 18   misfit: 0.31   stationDistributionRatio: 0.68   rmsAngDiffAccPref: 48.53   fracAcc30degPref: 0.30   qualityCode: D 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/1762661801852
Event info last updated: 2025.11.09-05:16:05 UTC
Event first association/location: 2025.11.09-04:30:37 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI