Early-est:     Off East Coast of Honshu, Japan    2025.11.09-14:41:17.44    q:B      mb:4.9    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: 4.9 [33]    Mwp: - [0]    Mwpd: - [0] Region: Off East Coast of Honshu, Japan Origin Time: 2025.11.09-14:41:17.44 UTC Hypocenter: lat: 39.85°  lon: 143.29°  [+/-15km]    depth: 10km  [+/-14km] Location Quality: qualityCode:  B     stdErr: 1.1s   assocPhases: 67   usedPhases: 41 minDist: 1.9°   maxDist: 142.0°   AzGap: 142°   2ndAzGap: 170°   atten: -0.66 [+/-0.16] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 15km   azMaxHorUnc: 106° 68%ConfEllipsoid:   semiMajorAxisLength: 19km   majorAxisAzimuth: 289°   majorAxisPlunge: 5°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 20°   intermediateAxisPlunge: 11°   semiMinorAxisLength: 14km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.5 [27]    Td: -s [0]    Td*T50Ex: - [0]    To: 19.9s [19] Closest plate boundaries:    Pacific \ Okhotsk [subduction zone]: distance: ~80km    Okhotsk / Pacific [subduction zone]: distance: ~150km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 19km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (80km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        10km        10km        10km Slab depth at epicenter:        19km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 64°   dip: 14°   rake: 36° Nodal Plane 2: strike: 299°   dip: 82°   rake: 102° Quality: azimuthalGap: -1°   stationPolarityCount: 40   misfitWeightCount: 5.6   misfit: 0.06   stationDistributionRatio: 0.29   meanDistP: 29.1   meanDistT: 35.3   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: 147°   dip: 82°   rake: -165° Nodal Plane 2: strike: 55°   dip: 75°   rake: -8° Quality: azimuthalGap: 142°   stationPolarityCount: 40   misfit: 0.32   stationDistributionRatio: 0.62   rmsAngDiffAccPref: 44.60   fracAcc30degPref: 0.45   qualityCode: D 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/1762699278209
Event info last updated: 2025.11.09-15:41:48 UTC
Event first association/location: 2025.11.09-14:53:13 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI