Early-est:     Hokkaido, Japan Region    2025.12.11-22:09:17.85    q:A      mb:5.2    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: 5.2 [93]    Mwp: - [0]    Mwpd: - [0] Region: Hokkaido, Japan Region Origin Time: 2025.12.11-22:09:17.85 UTC Hypocenter: lat: 41.07°  lon: 143.13°  [+/-11km]    depth: 11km  [+/-8km] Location Quality: qualityCode:  A     stdErr: 1.6s   assocPhases: 153   usedPhases: 107 minDist: 0.9°   maxDist: 151.8°   AzGap: 99°   2ndAzGap: 157°   atten: -0.85 [+/-0.14] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 6km   maxHorUnc: 11km   azMaxHorUnc: 118° 68%ConfEllipsoid:   semiMajorAxisLength: 13km   majorAxisAzimuth: 297°   majorAxisPlunge: 9°   semiIntermediateAxisLength: 8km   intermediateAxisAzimuth: 197°   intermediateAxisPlunge: 47°   semiMinorAxisLength: 6km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.5 [67]    Td: 2.3Xs [3]    Td*T50Ex: - [0]    To: 5.6s [58] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~110km    Okhotsk / Pacific [subduction zone]: distance: ~110km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 31km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (110km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        11km        11km        11km Slab depth at epicenter:        31km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 36°   dip: 54°   rake: 157° Nodal Plane 2: strike: 140°   dip: 72°   rake: 38° Quality: azimuthalGap: -1°   stationPolarityCount: 97   misfitWeightCount: 10.4   misfit: 0.19   stationDistributionRatio: 0.30   meanDistP: 36.4   meanDistT: 33.0   qualityCode: C 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: 154°   stationPolarityCount: 97   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: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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/1765490961259
Event info last updated: 2025.12.11-23:09:48 UTC
Event first association/location: 2025.12.11-22:16:04 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI