Early-est:     Kuril Islands    2025.12.10-09:25:30.92    q:C      mb:4.4    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: 4.4 [17]    Mwp: - [0]    Mwpd: - [0] Region: Kuril Islands Origin Time: 2025.12.10-09:25:30.92 UTC Hypocenter: lat: 48.75°  lon: 153.75°  [+/-13km]    depth: 137km  [+/-17km] Location Quality: qualityCode:  C     stdErr: 0.6s   assocPhases: 55   usedPhases: 18 minDist: 5.3°   maxDist: 126.4°   AzGap: 114°   2ndAzGap: 145°   atten: -0.92 [+/-0.22] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 10km   maxHorUnc: 13km   azMaxHorUnc: 97° 68%ConfEllipsoid:   semiMajorAxisLength: 17km   majorAxisAzimuth: 98°   majorAxisPlunge: 52°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 275°   intermediateAxisPlunge: 38°   semiMinorAxisLength: 13km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.0 [6]    Td: -s [0]    Td*T50Ex: - [0]    To: 1.0Xs [3] Closest plate boundaries:    Okhotsk / Pacific [subduction zone]: distance: ~190km Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 79km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (190km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        137km        137km        137km Slab depth at epicenter:        79km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 108°   dip: 27°   rake: -154° Nodal Plane 2: strike: 355°   dip: 78°   rake: -65° Quality: azimuthalGap: -1°   stationPolarityCount: 17   misfitWeightCount: 4.3   misfit: 0.08   stationDistributionRatio: 0.62   meanDistP: 33.2   meanDistT: 39.3   qualityCode: D 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: 157°   dip: 22°   rake: -96° Nodal Plane 2: strike: 344°   dip: 68°   rake: -87° Quality: azimuthalGap: 114°   stationPolarityCount: 17   misfit: 0.18   stationDistributionRatio: 0.62   rmsAngDiffAccPref: 37.81   fracAcc30degPref: 0.48   qualityCode: C 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/1765358730921
Event info last updated: 2025.12.10-10:25:35 UTC
Event first association/location: 2025.12.10-10:15:35 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI