Early-est:     Leeward Islands    2026.03.31-09:22:39.31    q:C      mb:4.6*    Mwp:-    Mwpd:-    Td*T50Ex:-     fmamp_polarity:./hypo.1774948959124.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1774948959124.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1774948959124.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: 4.6* [17]    Mwp: 6.2X [1]    Mwpd: - [0]
Region: Leeward Islands
Origin Time: 2026.03.31-09:22:39.31 UTC
Hypocenter: lat: 19.23°  lon: -63.45°  [+/-32km]    depth: 15km  [+/-22km]
Location Quality: qualityCode:  C     stdErr: 2.4s   assocPhases: 22   usedPhases: 20
minDist: 2.2°   maxDist: 148.8°   AzGap: 126°   2ndAzGap: 165°   atten: -2.67 [+/-0.16]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 16km   maxHorUnc: 32km   azMaxHorUnc: 35°
68%ConfEllipsoid:   semiMajorAxisLength: 40km   majorAxisAzimuth: 213°   majorAxisPlunge: 15°   semiIntermediateAxisLength: 24km   intermediateAxisAzimuth: 109°   intermediateAxisPlunge: 44°   semiMinorAxisLength: 17km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.5 [14]    Td: 0.8Xs [1]    Td*T50Ex: - [0]    To: 28.8s [14]
Closest plate boundaries:
   Caribbean - North America [oceanic transform fault]: distance: ~50km
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 (50km)
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   -
   -
   -
Td*To:
     -
     -
     -
Mwp magnitude:
       -
       -
       -
Hypocenter depth:
       15km
       15km
       15km
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.1774948959124.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 1°   dip: 7°   rake: -105°
Nodal Plane 2: strike: 196°   dip: 84°   rake: -88°
Quality: azimuthalGap: -1°   stationPolarityCount: 18   misfitWeightCount: 3.3   misfit: 0.03   stationDistributionRatio: 0.69   meanDistP: 47.4   meanDistT: 49.2   qualityCode: D
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1774948959124.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.1774948959124.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D)
Nodal Plane 1: strike: 304°   dip: 35°   rake: -111°
Nodal Plane 2: strike: 149°   dip: 58°   rake: -76°
Quality: azimuthalGap: 125°   stationPolarityCount: 18   misfit: 0.23   stationDistributionRatio: 0.70   rmsAngDiffAccPref: 40.44   fracAcc30degPref: 0.47   qualityCode: D
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1774948959124.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1774948959124
Event info last updated: 2026.03.31-10:21:00 UTC
Event first association/location: 2026.03.31-09:32:02 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA