Early-est:     Off East Coast of Honshu, Japan    2025.11.10-00:40:09.37    q:B      mb:4.8    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: 4.8 [24]    Mwp: - [0]    Mwpd: - [0] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.10-00:40:09.37 UTC Hypocenter: lat: 39.49°  lon: 143.20°  [+/-17km]    depth: 10km  [+/-15km] Location Quality: qualityCode:  B     stdErr: 1.2s   assocPhases: 56   usedPhases: 33 minDist: 2.1°   maxDist: 152.8°   AzGap: 73°   2ndAzGap: 135°   atten: -1.10 [+/-0.25] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 12km   maxHorUnc: 17km   azMaxHorUnc: 105° 68%ConfEllipsoid:   semiMajorAxisLength: 22km   majorAxisAzimuth: 104°   majorAxisPlunge: 12°   semiIntermediateAxisLength: 15km   intermediateAxisAzimuth: 3°   intermediateAxisPlunge: 41°   semiMinorAxisLength: 14km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.4 [14]    Td: -s [0]    Td*T50Ex: - [0]    To: 21.4s [10] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~90km    Okhotsk / Pacific [subduction zone]: distance: ~180km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 18km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (90km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        18km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 73°   dip: 30°   rake: -45° Nodal Plane 2: strike: 204°   dip: 69°   rake: -112° Quality: azimuthalGap: -1°   stationPolarityCount: 28   misfitWeightCount: 5.8   misfit: 0.12   stationDistributionRatio: 0.50   meanDistP: 33.9   meanDistT: 43.3   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH): Nodal Plane 1: strike: 238°   dip: 70°   rake: -144° Nodal Plane 2: strike: 134°   dip: 57°   rake: -25° Quality: azimuthalGap: 72°   stationPolarityCount: 28   misfit: 0.21   stationDistributionRatio: 0.60   rmsAngDiffAccPref: 14.66   fracAcc30degPref: 0.99   qualityCode: B 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/1762735209695
Event info last updated: 2025.11.10-01:40:33 UTC
Event first association/location: 2025.11.10-00:51:51 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI