Early-est:     Volcano Islands, Japan Region    2026.10.12-00:53:12.99    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 [12]    Mwp: - [0]    Mwpd: - [0] Region: Volcano Islands, Japan Region Origin Time: 2026.10.12-00:53:12.99 UTC Hypocenter: lat: 25.14°  lon: 141.03°  [+/-20km]    depth: 202km  [+/-21km] Location Quality: qualityCode:  B     stdErr: 1.4s   assocPhases: 49   usedPhases: 20 minDist: 2.2°   maxDist: 151.4°   AzGap: 103°   2ndAzGap: 125°   atten: -1.32 [+/-0.38] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 20km   azMaxHorUnc: 86° 68%ConfEllipsoid:   semiMajorAxisLength: 27km   majorAxisAzimuth: 84°   majorAxisPlunge: 30°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 301°   intermediateAxisPlunge: 54°   semiMinorAxisLength: 15km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.3 [10]    Td: -s [0]    Td*T50Ex: - [0]    To: 0.9s [6] Closest plate boundaries:    Philippine Sea / Pacific [subduction zone]: distance: ~210km Subduction geometry:    Zone: Izu-Bonin    Slab depth at epicenter: 176km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (210km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        202km        202km        202km Slab depth at epicenter:        176km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 154°   dip: 44°   rake: -20° Nodal Plane 2: strike: 258°   dip: 76°   rake: -132° Quality: azimuthalGap: -1°   stationPolarityCount: 19   misfitWeightCount: 6.8   misfit: 0.06   stationDistributionRatio: 0.56   meanDistP: 35.9   meanDistT: 34.6   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: 282°   dip: 60°   rake: -105° Nodal Plane 2: strike: 130°   dip: 33°   rake: -66° Quality: azimuthalGap: 94°   stationPolarityCount: 19   misfit: 0.30   stationDistributionRatio: 0.76   rmsAngDiffAccPref: 40.59   fracAcc30degPref: 0.46   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/1791766391711
Event info last updated: 2026.10.12-01:54:02 UTC
Event first association/location: 2026.10.12-01:02:17 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI