Early-est:     Near East Coast of Honshu, Japan    2026.06.24-22:30:17.67    q:B      mb:5.7    Mwp:6.9*    Mwpd:-    Td*T50Ex:3.1     fmamp_polarity:./hypo.1782340213727.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1782340213727.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1782340213727.mech.hash.thumb.jpg

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

Earthquake Details:
Magnitude: mb: 5.7 [153]    Mwp: 6.9* [20]    Mwpd: 7.1Xinv [21]
Region: Near East Coast of Honshu, Japan
Origin Time: 2026.06.24-22:30:17.67 UTC
Hypocenter: lat: 40.05°  lon: 142.28°  [+/-15km]    depth: 70km  [+/-28km]
Location Quality: qualityCode:  B     stdErr: 1.3s   assocPhases: 276   usedPhases: 207
minDist: 1.2°   maxDist: 158.7°   AzGap: 18°   2ndAzGap: 29°   atten: -1.14 [+/-0.16]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 15km   azMaxHorUnc: 112°
68%ConfEllipsoid:   semiMajorAxisLength: 31km   majorAxisAzimuth: 242°   majorAxisPlunge: 64°   semiIntermediateAxisLength: 18km   intermediateAxisAzimuth: 140°   intermediateAxisPlunge: 6°   semiMinorAxisLength: 12km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.6 [161]    Td: 5.4s [13]    Td*T50Ex: 3.1 [13]    To: 27.2s [160]
Closest plate boundaries:
   Pacific \ Okhotsk [subduction zone]: distance: ~170km
   Okhotsk / Pacific [subduction zone]: distance: ~200km
Subduction geometry:    Zone: Kamchatka/Kurils/Japan: DEBUG: error: [Errno 2] No such file or directory: 'gmt'    Slab depth at epicenter: error: evaluating slab depth: -999.9
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 YES (170km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   3.1
   3.1
   3.1
Td*To:
     146.9
     146.9
     146.9
Mwp magnitude:
       6.9*
       6.9*
       6.9*
Hypocenter depth:
       70km
       70km
       70km
Slab depth at epicenter:
       n/a
       -
       -
Tsunami and Rupture predictions (TEST!): No prediction: Event too small (Mwp<7.0) or too few Mwp readings (N<20)
./hypo.1782340213727.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):
Nodal Plane 1: strike: 273°   dip: 38°   rake: 141°
Nodal Plane 2: strike: 35°   dip: 67°   rake: 58°
Quality: azimuthalGap: -1°   stationPolarityCount: 161   misfitWeightCount: 29.4   misfit: 0.14   stationDistributionRatio: 0.62   meanDistP: 22.3   meanDistT: 18.4   qualityCode: B
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1782340213727.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 304°   dip: 35°   rake: 152°
Nodal Plane 2: strike: 58°   dip: 74°   rake: 58°
Quality: azimuthalGap: -1°   stationPolarityCount: 9   misfitWeightCount: 3.1   misfit: 0.00   stationDistributionRatio: 0.56   meanDistP: 51.7   meanDistT: 47.9   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity_waveform
./hypo.1782340213727.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 262°   dip: 29°   rake: 136°
Nodal Plane 2: strike: 33°   dip: 70°   rake: 68°
Quality: azimuthalGap: 38°   stationPolarityCount: 161   misfit: 0.21   stationDistributionRatio: 0.72   rmsAngDiffAccPref: 27.16   fracAcc30degPref: 0.75   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1782340213727.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1782340213727
Event info last updated: 2026.06.24-23:29:02 UTC
Event first association/location: 2026.06.24-22:37:03 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA