Early-est:     Near East Coast of Honshu, Japan    2026.10.11-16:24:22.68    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 [5]    Mwp: - [0]    Mwpd: - [0] Region: Near East Coast of Honshu, Japan Origin Time: 2026.10.11-16:24:22.68 UTC Hypocenter: lat: 35.51°  lon: 140.83°  [+/-16km]    depth: 10km  [+/-28km] Location Quality: qualityCode:  C     stdErr: 1.6s   assocPhases: 14   usedPhases: 13 minDist: 2.4°   maxDist: 155.2°   AzGap: 74°   2ndAzGap: 102°   atten: -1.06 [+/-0.71] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 15km   maxHorUnc: 16km   azMaxHorUnc: 109° 68%ConfEllipsoid:   semiMajorAxisLength: 29km   majorAxisAzimuth: 228°   majorAxisPlunge: 76°   semiIntermediateAxisLength: 20km   intermediateAxisAzimuth: 118°   intermediateAxisPlunge: 5°   semiMinorAxisLength: 18km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.8X [2]    Td: -s [0]    Td*T50Ex: - [0]    To: -s [0] Closest plate boundaries:    Okhotsk - Philippine Sea [oceanic convergent boundary]: distance: ~100km    Pacific \ Okhotsk [subduction zone]: distance: ~120km    Philippine Sea / Pacific [subduction zone]: distance: ~170km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 36km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (120km)  YES (100km)  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        36km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 144°   dip: 9°   rake: -146° Nodal Plane 2: strike: 20°   dip: 85°   rake: -83° Quality: azimuthalGap: -1°   stationPolarityCount: 8   misfitWeightCount: 4.7   misfit: 0.13   stationDistributionRatio: 0.25   meanDistP: 42.9   meanDistT: 47.7   qualityCode: D 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: 193°   stationPolarityCount: 8   misfit: 0.99   stationDistributionRatio: 0.61   rmsAngDiffAccPref: 27.05   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: 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/1791735862680
Event info last updated: 2026.10.11-17:24:32 UTC
Event first association/location: 2026.10.11-17:24:32 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI