Early-est:     Kuril Islands    2026.09.28-04:42:57.44    q:B      mb:4.5*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1790570577213.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1790570577213.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1790570577213.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: 4.5* [21]    Mwp: 5.4X [1]    Mwpd: 5.6Xinv [1]
Region: Kuril Islands
Origin Time: 2026.09.28-04:42:57.44 UTC
Hypocenter: lat: 48.82°  lon: 151.75°  [+/-14km]    depth: 246km  [+/-18km]
Location Quality: qualityCode:  B     stdErr: 1.2s   assocPhases: 47   usedPhases: 28
minDist: 6.3°   maxDist: 78.9°   AzGap: 148°   2ndAzGap: 152°   atten: -0.90 [+/-0.37]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 8km   maxHorUnc: 14km   azMaxHorUnc: 135°
68%ConfEllipsoid:   semiMajorAxisLength: 19km   majorAxisAzimuth: 311°   majorAxisPlunge: 46°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 141°   intermediateAxisPlunge: 44°   semiMinorAxisLength: 10km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.0 [15]    Td: 0.6Xs [2]    Td*T50Ex: - [0]    To: 1.1s [15]
Closest plate boundaries:
   Okhotsk / Pacific [subduction zone]: distance: ~310km
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 (310km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       246km
       246km
       246km
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.1790570577213.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 283°   dip: 29°   rake: 172°
Nodal Plane 2: strike: 20°   dip: 86°   rake: 62°
Quality: azimuthalGap: -1°   stationPolarityCount: 24   misfitWeightCount: 7.3   misfit: 0.14   stationDistributionRatio: 0.61   meanDistP: 50.1   meanDistT: 46.2   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1790570577213.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.1790570577213.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 306°   dip: 27°   rake: -158°
Nodal Plane 2: strike: 197°   dip: 80°   rake: -65°
Quality: azimuthalGap: 125°   stationPolarityCount: 24   misfit: 0.24   stationDistributionRatio: 0.72   rmsAngDiffAccPref: 30.91   fracAcc30degPref: 0.75   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1790570577213.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1790570577213
Event info last updated: 2026.09.28-05:41:00 UTC
Event first association/location: 2026.09.28-04:50:01 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA