Early-est:     Southwestern Ryukyu Isl., Japan    2026.10.05-13:30:47.26    q:B      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 [40]    Mwp: - [0]    Mwpd: - [0] Region: Southwestern Ryukyu Isl., Japan Origin Time: 2026.10.05-13:30:47.26 UTC Hypocenter: lat: 24.97°  lon: 123.39°  [+/-15km]    depth: 163km  [+/-16km] Location Quality: qualityCode:  B     stdErr: 0.9s   assocPhases: 67   usedPhases: 48 minDist: 0.6°   maxDist: 91.3°   AzGap: 79°   2ndAzGap: 85°   atten: -1.00 [+/-0.21] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 15km   azMaxHorUnc: 38° 68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 31°   majorAxisPlunge: 8°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 295°   intermediateAxisPlunge: 36°   semiMinorAxisLength: 16km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.0 [12]    Td: -s [0]    Td*T50Ex: - [0]    To: 1.1s [10] Closest plate boundaries:    Yangtze - Okinawa [continental rift boundary]: distance: ~20km    Okinawa - Philippine Sea [oceanic convergent boundary]: distance: ~170km    Philippine Sea - Yangtze [continental transform fault]: distance: ~190km    Okinawa / Philippine Sea [subduction zone]: distance: ~280km Subduction geometry:    Zone: Ryukyu    Slab depth at epicenter: 100km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (280km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        163km        163km        163km Slab depth at epicenter:        100km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 40°   dip: 29°   rake: -179° Nodal Plane 2: strike: 309°   dip: 89°   rake: -61° Quality: azimuthalGap: -1°   stationPolarityCount: 43   misfitWeightCount: 15.5   misfit: 0.21   stationDistributionRatio: 0.49   meanDistP: 26.4   meanDistT: 28.2   qualityCode: C 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: 215°   dip: 21°   rake: -54° Nodal Plane 2: strike: 358°   dip: 73°   rake: -103° Quality: azimuthalGap: 40°   stationPolarityCount: 43   misfit: 0.35   stationDistributionRatio: 0.77   rmsAngDiffAccPref: 33.53   fracAcc30degPref: 0.58   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: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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: nan° Nodal Plane 2: strike: nan°   dip: nan°   rake: nan° 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/1791207044628
Event info last updated: 2026.10.05-14:31:03 UTC
Event first association/location: 2026.10.05-13:35:36 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI