Early-est:     West of Macquarie Island    2026.08.13-17:39:39.38    q:C      mb:4.7*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1786642774269.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1786642774269.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1786642774269.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: 4.7* [11]    Mwp: - [0]    Mwpd: - [0]
Region: West of Macquarie Island
Origin Time: 2026.08.13-17:39:39.38 UTC
Hypocenter: lat: -56.85°  lon: 147.51°  [+/-13km]    depth: 90km  [+/-20km]
Location Quality: qualityCode:  C     stdErr: 0.9s   assocPhases: 18   usedPhases: 15
minDist: 19.3°   maxDist: 147.1°   AzGap: 144°   2ndAzGap: 200°   atten: -1.30 [+/-0.55]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 11km   maxHorUnc: 13km   azMaxHorUnc: 5°
68%ConfEllipsoid:   semiMajorAxisLength: 20km   majorAxisAzimuth: 351°   majorAxisPlunge: 68°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 193°   intermediateAxisPlunge: 21°   semiMinorAxisLength: 14km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.5 [10]    Td: -s [0]    Td*T50Ex: - [0]    To: 15.0s [8]
Closest plate boundaries:
   Australia - Antarctica [oceanic transform fault]: distance: ~30km
Subduction geometry: none or not available
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 no
 no
 YES (30km)
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       90km
       90km
       90km
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.1786642774269.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 27°   dip: 53°   rake: -37°
Nodal Plane 2: strike: 141°   dip: 62°   rake: -137°
Quality: azimuthalGap: -1°   stationPolarityCount: 12   misfitWeightCount: 2.8   misfit: 0.09   stationDistributionRatio: 0.45   meanDistP: 54.5   meanDistT: 53.4   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1786642774269.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.1786642774269.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (No solution available)
Nodal Plane 1: strike: 999°   dip: 99°   rake: 999°
Nodal Plane 2: strike: 324°   dip: 13°   rake: 135°
Quality: azimuthalGap: 171°   stationPolarityCount: 12   misfit: 0.99   stationDistributionRatio: 0.00   rmsAngDiffAccPref: 0.00   fracAcc30degPref: 0.00   qualityCode: E
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1786642774269.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1786642774269
Event info last updated: 2026.08.13-18:38:00 UTC
Event first association/location: 2026.08.13-17:50:00 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA