Early-est:     Santa Cruz Islands Region    2026.08.10-11:50:27.38    q:A      mb:4.8*    Mwp:-    Mwpd:-    Td*T50Ex:0.4     fmamp_polarity:./hypo.1786362627204.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1786362627204.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1786362627204.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: 4.8* [48]    Mwp: - [0]    Mwpd: - [0]
Region: Santa Cruz Islands Region
Origin Time: 2026.08.10-11:50:27.38 UTC
Hypocenter: lat: -12.92°  lon: 168.97°  [+/-14km]    depth: 655km  [+/-17km]
Location Quality: qualityCode:  A     stdErr: 1.0s   assocPhases: 89   usedPhases: 59
minDist: 8.6°   maxDist: 146.7°   AzGap: 48°   2ndAzGap: 53°   atten: -1.86 [+/-0.18]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 14km   azMaxHorUnc: 58°
68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 227°   majorAxisPlunge: 44°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 106°   intermediateAxisPlunge: 27°   semiMinorAxisLength: 16km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.3 [34]    Td: 1.4s [6]    Td*T50Ex: 0.4 [6]    To: 1.2s [34]
Closest plate boundaries:
   New Hebrides - Pacific [continental rift boundary]: distance: ~80km
   Pacific / Australia [subduction zone]: distance: ~320km
   New Hebrides / Australia [subduction zone]: distance: ~320km
Subduction geometry: none or not available
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 YES (320km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   0.4
   0.4
   0.4
Td*To:
     1.7
     1.7
     1.7
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       655km
       655km
       655km
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.1786362627204.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 15°   dip: 53°   rake: 136°
Nodal Plane 2: strike: 135°   dip: 57°   rake: 46°
Quality: azimuthalGap: -1°   stationPolarityCount: 48   misfitWeightCount: 17.5   misfit: 0.19   stationDistributionRatio: 0.54   meanDistP: 25.8   meanDistT: 39.2   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1786362627204.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.1786362627204.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 183°   dip: 86°   rake: 101°
Nodal Plane 2: strike: 290°   dip: 12°   rake: 18°
Quality: azimuthalGap: 73°   stationPolarityCount: 48   misfit: 0.27   stationDistributionRatio: 0.66   rmsAngDiffAccPref: 23.25   fracAcc30degPref: 0.74   qualityCode: C
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1786362627204.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1786362627204
Event info last updated: 2026.08.10-12:49:03 UTC
Event first association/location: 2026.08.10-11:55:00 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA