Early-est:     Near East Coast of Honshu, Japan    2025.12.12-02:44:13.39    q:A      mb:5.7    Mwp:6.7    Mwpd:-    Td*T50Ex:3.0     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: 5.7 [267]    Mwp: 6.7 [212]    Mwpd: 6.9Xinv [196] Region: Near East Coast of Honshu, Japan Origin Time: 2025.12.12-02:44:13.39 UTC Hypocenter: lat: 40.78°  lon: 142.93°  [+/-6km]    depth: 15km  [+/-7km] Location Quality: qualityCode:  A     stdErr: 1.4s   assocPhases: 448   usedPhases: 336 minDist: 1.2°   maxDist: 161.2°   AzGap: 11°   2ndAzGap: 17°   atten: -1.20 [+/-0.14] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 5km   maxHorUnc: 6km   azMaxHorUnc: 94° 68%ConfEllipsoid:   semiMajorAxisLength: 7km   majorAxisAzimuth: 86°   majorAxisPlunge: 25°   semiIntermediateAxisLength: 7km   intermediateAxisAzimuth: 310°   intermediateAxisPlunge: 58°   semiMinorAxisLength: 5km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.6 [263]    Td: 5.1s [38]    Td*T50Ex: 3.0 [38]    To: 34.5s [246] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~130km    Okhotsk / Pacific [subduction zone]: distance: ~130km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 33km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (130km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    3.0    3.0    3.0 Td*To:      175.9      175.9      175.9 Mwp magnitude:        6.7        6.7        6.7 Hypocenter depth:        15km        15km        15km Slab depth at epicenter:        33km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY): Nodal Plane 1: strike: 124°   dip: 14°   rake: 36° Nodal Plane 2: strike: 359°   dip: 82°   rake: 102° Quality: azimuthalGap: -1°   stationPolarityCount: 320   misfitWeightCount: 51.1   misfit: 0.11   stationDistributionRatio: 0.59   meanDistP: 12.3   meanDistT: 11.0   qualityCode: A 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: 337°   dip: 80°   rake: 102° Nodal Plane 2: strike: 107°   dip: 16°   rake: 40° Quality: azimuthalGap: 11°   stationPolarityCount: 320   misfit: 0.14   stationDistributionRatio: 0.61   rmsAngDiffAccPref: 29.74   fracAcc30degPref: 0.64   qualityCode: C Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 169°   dip: 7°   rake: 80° Nodal Plane 2: strike: 359°   dip: 83°   rake: 91° Quality: azimuthalGap: -1°   stationPolarityCount: 226   misfitWeightCount: 34.3   misfit: 9999.90   stationDistributionRatio: 0.26   meanDistP: 34.4   meanDistT: 24.2   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_aref
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 137°   dip: 7°   rake: 52° Nodal Plane 2: strike: 355°   dip: 85°   rake: 94° Quality: azimuthalGap: -1°   stationPolarityCount: 197   misfitWeightCount: 27.5   misfit: 9999.90   stationDistributionRatio: 0.52   meanDistP: 34.6   meanDistT: 24.4   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_mwp

Event ID: smi:KOERI/ee/event/1765507458386
Event info last updated: 2025.12.12-03:45:59 UTC
Event first association/location: 2025.12.12-02:47:48 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI