Early-est:     Western Honshu, Japan    2025.06.07-14:46:16.73    q:B      mb:4.2    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1749307576733.mech.fmamp_polarity.thumb.jpg     hash:./hypo.1749307576733.mech.hash.thumb.jpg     fmamp_amp_aref:./hypo.1749307576733.mech.fmamp_amp_aref.thumb.jpg     fmamp_amp_mwp:./hypo.1749307576733.mech.fmamp_amp_mwp.thumb.jpg

Automatic solution - this event has not been reviewed by a seismologist
Automatically determined event information may be incorrect!

Earthquake Details:
Magnitude: mb: 4.2 [13]    Mwp: 4.2X [2]    Mwpd: 5.5Xinv [1]
Region: Western Honshu, Japan
Origin Time: 2025.06.07-14:46:16.73 UTC
Hypocenter: lat: 35.87°  lon: 135.69°  [+/-24km]    depth: 348km  [+/-20km]
Location Quality: qualityCode:  B     stdErr: 0.7s   assocPhases: 48   usedPhases: 16
minDist: 1.2°   maxDist: 85.8°   AzGap: 40°   2ndAzGap: 66°   atten: -1.00 [+/-0.23]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 24km   azMaxHorUnc: 139°
68%ConfEllipsoid:   semiMajorAxisLength: 31km   majorAxisAzimuth: 139°   majorAxisPlunge: 21°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 297°   intermediateAxisPlunge: 68°   semiMinorAxisLength: 16km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.0 [5]    Td: -s [0]    Td*T50Ex: - [0]    To: 1.1Xs [1]
Closest plate boundaries:
Subduction geometry:    Zone: Kamchatka/Kurils/Japan    Slab depth at epicenter: 276km
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 no
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       348km
       348km
       348km
Slab depth at epicenter:
       276km
       -
       -
./hypo.1749307576733.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 228°   dip: 73°   rake: 4°
Nodal Plane 2: strike: 137°   dip: 86°   rake: 163°
Quality: azimuthalGap: -1°   stationPolarityCount: 18   misfitWeightCount: 11.6   misfit: 0.06   stationDistributionRatio: 0.40   meanDistP: 56.5   meanDistT: 30.3   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1749307576733.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 328°   dip: 76°   rake: -157°
Nodal Plane 2: strike: 232°   dip: 67°   rake: -15°
Quality: azimuthalGap: 84°   stationPolarityCount: 18   misfit: 0.19   stationDistributionRatio: 0.69   rmsAngDiffAccPref: 24.81   fracAcc30degPref: 0.81   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1749307576733.mech.hash.mechanism.jpg
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
./hypo.1749307576733.mech.fmamp_amp_aref.mechanism.jpg
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
./hypo.1749307576733.mech.fmamp_amp_mwp.mechanism.jpg

Event ID: smi:KOERI/ee/event/1749307576733
Event info last updated: 2025.06.07-15:46:31 UTC
Event first association/location: 2025.06.07-15:46:30 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI