Early-est:     Volcano Islands, Japan Region    2026.10.04-11:12:49.71    q:B      mb:5.1*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1791112368351.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1791112368351.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1791112368351.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: 5.1* [50]    Mwp: 5.5X [2]    Mwpd: 6.0Xinv [2]
Region: Volcano Islands, Japan Region
Origin Time: 2026.10.04-11:12:49.71 UTC
Hypocenter: lat: 22.75°  lon: 144.62°  [+/-17km]    depth: 9km  [+/-14km]
Location Quality: qualityCode:  B     stdErr: 1.7s   assocPhases: 97   usedPhases: 64
minDist: 4.9°   maxDist: 149.2°   AzGap: 44°   2ndAzGap: 54°   atten: -0.70 [+/-0.21]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 17km   azMaxHorUnc: 40°
68%ConfEllipsoid:   semiMajorAxisLength: 21km   majorAxisAzimuth: 40°   majorAxisPlunge: 6°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 308°   intermediateAxisPlunge: 16°   semiMinorAxisLength: 13km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.5 [47]    Td: 3.7Xs [3]    Td*T50Ex: - [0]    To: 27.5s [43]
Closest plate boundaries:
   Mariana / Pacific [subduction zone]: distance: ~60km
   Philippine Sea - Mariana [oceanic spreading ridge]: distance: ~180km
   Philippine Sea / Pacific [subduction zone]: distance: ~210km
Subduction geometry:    Zone: Izu-Bonin: 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 (60km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       9km
       9km
       9km
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.1791112368351.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 116°   dip: 9°   rake: -9°
Nodal Plane 2: strike: 215°   dip: 89°   rake: -99°
Quality: azimuthalGap: -1°   stationPolarityCount: 40   misfitWeightCount: 7.2   misfit: 0.21   stationDistributionRatio: 0.42   meanDistP: 51.9   meanDistT: 48.0   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1791112368351.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (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/_polarity_waveform
./hypo.1791112368351.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 297°   dip: 66°   rake: -166°
Nodal Plane 2: strike: 201°   dip: 77°   rake: -24°
Quality: azimuthalGap: 82°   stationPolarityCount: 40   misfit: 0.31   stationDistributionRatio: 0.74   rmsAngDiffAccPref: 32.50   fracAcc30degPref: 0.79   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1791112368351.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1791112368351
Event info last updated: 2026.10.04-12:11:01 UTC
Event first association/location: 2026.10.04-11:21:02 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA