Early-est:     Santa Cruz Islands    2026.08.08-18:28:28.97    q:C      mb:4.5*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1786213710420.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1786213710420.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1786213710420.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* [9]    Mwp: - [0]    Mwpd: - [0]
Region: Santa Cruz Islands
Origin Time: 2026.08.08-18:28:28.97 UTC
Hypocenter: lat: -10.64°  lon: 165.59°  [+/-22km]    depth: 93km  [+/-25km]
Location Quality: qualityCode:  C     stdErr: 1.2s   assocPhases: 36   usedPhases: 13
minDist: 10.0°   maxDist: 141.8°   AzGap: 81°   2ndAzGap: 159°   atten: -2.00 [+/-0.37]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 14km   maxHorUnc: 22km   azMaxHorUnc: 15°
68%ConfEllipsoid:   semiMajorAxisLength: 33km   majorAxisAzimuth: 194°   majorAxisPlunge: 42°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 94°   intermediateAxisPlunge: 11°   semiMinorAxisLength: 16km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.3 [5]    Td: -s [0]    Td*T50Ex: - [0]    To: 2.6s [5]
Closest plate boundaries:
   Pacific / Australia [subduction zone]: distance: ~90km
Subduction geometry: none or not available
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 YES (90km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       93km
       93km
       93km
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.1786213710420.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 38°   dip: 1°   rake: -49°
Nodal Plane 2: strike: 177°   dip: 89°   rake: -91°
Quality: azimuthalGap: -1°   stationPolarityCount: 9   misfitWeightCount: 5.0   misfit: 0.00   stationDistributionRatio: 0.52   meanDistP: 45.1   meanDistT: 45.3   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1786213710420.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.1786213710420.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 237°   dip: 34°   rake: 176°
Nodal Plane 2: strike: 330°   dip: 88°   rake: 56°
Quality: azimuthalGap: 147°   stationPolarityCount: 9   misfit: 0.26   stationDistributionRatio: 0.68   rmsAngDiffAccPref: 40.17   fracAcc30degPref: 0.57   qualityCode: D
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1786213710420.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1786213710420
Event info last updated: 2026.08.08-19:27:00 UTC
Event first association/location: 2026.08.08-18:41:02 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA