Early-est:     Off East Coast of Honshu, Japan    2025.11.08-22:15:08.71    q:A      mb:5.3    Mwp:6.0    Mwpd:-    Td*T50Ex:2.1     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: 5.3 [162]    Mwp: 6.0 [63]    Mwpd: 6.2Xinv [52] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.08-22:15:08.71 UTC Hypocenter: lat: 39.37°  lon: 143.44°  [+/-8km]    depth: 10km  [+/-7km] Location Quality: qualityCode:  A     stdErr: 1.1s   assocPhases: 216   usedPhases: 193 minDist: 2.3°   maxDist: 160.2°   AzGap: 42°   2ndAzGap: 54°   atten: -1.19 [+/-0.14] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 7km   maxHorUnc: 8km   azMaxHorUnc: 139° 68%ConfEllipsoid:   semiMajorAxisLength: 10km   majorAxisAzimuth: 319°   majorAxisPlunge: 8°   semiIntermediateAxisLength: 8km   intermediateAxisAzimuth: 229°   intermediateAxisPlunge: 0°   semiMinorAxisLength: 7km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.8 [136]    Td: 2.7s [15]    Td*T50Ex: 2.1 [15]    To: 62.7s [120] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~70km    Okhotsk / Pacific [subduction zone]: distance: ~190km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 14km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (70km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    2.1    2.1    2.1 Td*To:      169.3      169.3      169.3 Mwp magnitude:        6.0        6.0        6.0 Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        14km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 112°   dip: 22°   rake: 32° Nodal Plane 2: strike: 353°   dip: 79°   rake: 109° Quality: azimuthalGap: -1°   stationPolarityCount: 160   misfitWeightCount: 21.2   misfit: 0.20   stationDistributionRatio: 0.65   meanDistP: 35.1   meanDistT: 23.2   qualityCode: C 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: 330°   dip: 56°   rake: 114° Nodal Plane 2: strike: 112°   dip: 41°   rake: 59° Quality: azimuthalGap: 41°   stationPolarityCount: 160   misfit: 0.19   stationDistributionRatio: 0.61   rmsAngDiffAccPref: 44.13   fracAcc30degPref: 0.35   qualityCode: D Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 301°   dip: 43°   rake: 98° Nodal Plane 2: strike: 110°   dip: 47°   rake: 83° Quality: azimuthalGap: -1°   stationPolarityCount: 61   misfitWeightCount: 6.1   misfit: 9999.90   stationDistributionRatio: 0.74   meanDistP: 48.1   meanDistT: 30.1   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_aref
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 137°   dip: 30°   rake: 40° Nodal Plane 2: strike: 12°   dip: 71°   rake: 114° Quality: azimuthalGap: -1°   stationPolarityCount: 55   misfitWeightCount: 5.2   misfit: 9999.90   stationDistributionRatio: 0.77   meanDistP: 41.1   meanDistT: 29.0   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_mwp

Event ID: smi:KOERI/ee/event/1762640109291
Event info last updated: 2025.11.08-23:15:09 UTC
Event first association/location: 2025.11.08-22:21:16 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI