Early-est:     East of Kuril Islands    2025.08.04-04:20:54.41    q:B      mb:5.2    Mwp:6.3*    Mwpd:-    Td*T50Ex:4.8     fmamp_polarity:./hypo.1754281253572.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1754281253572.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1754281253572.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: 5.2 [96]    Mwp: 6.3* [76]    Mwpd: 6.5Xinv [63]
Region: East of Kuril Islands
Origin Time: 2025.08.04-04:20:54.41 UTC
Hypocenter: lat: 48.71°  lon: 156.14°  [+/-29km]    depth: 5km  [+/-31km]
Location Quality: qualityCode:  B     stdErr: 1.7s   assocPhases: 175   usedPhases: 86
minDist: 4.6°   maxDist: 150.7°   AzGap: 98°   2ndAzGap: 109°   atten: -0.93 [+/-0.20]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 26km   maxHorUnc: 29km   azMaxHorUnc: 105°
68%ConfEllipsoid:   semiMajorAxisLength: 37km   majorAxisAzimuth: 296°   majorAxisPlunge: 24°   semiIntermediateAxisLength: 33km   intermediateAxisAzimuth: 40°   intermediateAxisPlunge: 28°   semiMinorAxisLength: 28km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.7 [75]    Td: 6.9s [20]    Td*T50Ex: 4.8 [20]    To: 53.4s [72]
Closest plate boundaries:
   Okhotsk / Pacific [subduction zone]: distance: ~60km
   North America / Pacific [subduction zone]: distance: ~900km
   Okhotsk / North America [subduction zone]: distance: ~900km
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 (60km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   4.8
   4.8
   4.8
Td*To:
     368.5
     368.5
     368.5
Mwp magnitude:
       6.3*
       6.3*
       6.3*
Hypocenter depth:
       5km
       5km
       5km
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.1754281253572.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 174°   dip: 17°   rake: 42°
Nodal Plane 2: strike: 43°   dip: 79°   rake: 103°
Quality: azimuthalGap: -1°   stationPolarityCount: 76   misfitWeightCount: 10.6   misfit: 0.03   stationDistributionRatio: 0.64   meanDistP: 39.9   meanDistT: 29.8   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1754281253572.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 112°   dip: 17°   rake: 0°
Nodal Plane 2: strike: 21°   dip: 90°   rake: 107°
Quality: azimuthalGap: -1°   stationPolarityCount: 22   misfitWeightCount: 3.6   misfit: 0.00   stationDistributionRatio: 0.67   meanDistP: 45.7   meanDistT: 39.8   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity_waveform
./hypo.1754281253572.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):
Nodal Plane 1: strike: 137°   dip: 14°   rake: 7°
Nodal Plane 2: strike: 41°   dip: 88°   rake: 103°
Quality: azimuthalGap: 127°   stationPolarityCount: 77   misfit: 0.11   stationDistributionRatio: 0.69   rmsAngDiffAccPref: 21.44   fracAcc30degPref: 0.79   qualityCode: B
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1754281253572.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1754281253572
Event info last updated: 2025.08.04-05:19:03 UTC
Event first association/location: 2025.08.04-04:26:01 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA