Early-est:     South Sandwich Islands Region    2025.12.08-18:41:16.62    q:A      mb:5.3    Mwp:-    Mwpd:-    Td*T50Ex:1.2     fmamp_polarity:     hash:     fmamp_amp_aref:     fmamp_amp_mwp:

Automatic solution - this event has not been reviewed by a seismologist
Automatically determined event information may be incorrect!

Earthquake Details: Magnitude: mb: 5.3 [59]    Mwp: - [0]    Mwpd: - [0] Region: South Sandwich Islands Region Origin Time: 2025.12.08-18:41:16.62 UTC Hypocenter: lat: -58.68°  lon: -25.14°  [+/-14km]    depth: 20km  [+/-14km] Location Quality: qualityCode:  A     stdErr: 1.4s   assocPhases: 127   usedPhases: 92 minDist: 10.1°   maxDist: 161.8°   AzGap: 36°   2ndAzGap: 46°   atten: -1.89 [+/-0.52] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 14km   azMaxHorUnc: 171° 68%ConfEllipsoid:   semiMajorAxisLength: 18km   majorAxisAzimuth: 351°   majorAxisPlunge: 1°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 261°   intermediateAxisPlunge: 1°   semiMinorAxisLength: 14km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.5 [53]    Td: 2.2s [5]    Td*T50Ex: 1.2 [5]    To: 26.2s [47] Closest plate boundaries:    Sandwich / South America [subduction zone]: distance: ~70km    Antarctica - South America [oceanic transform fault]: distance: ~200km    Sandwich - Antarctica [oceanic transform fault]: distance: ~200km Subduction geometry:    Zone: Scotia    Slab depth at epicenter: 20km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (70km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    1.2    1.2    1.2 Td*To:      57.6      57.6      57.6 Mwp magnitude:        -        -        - Hypocenter depth:        20km        20km        20km Slab depth at epicenter:        20km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 75°   dip: 21°   rake: -24° Nodal Plane 2: strike: 187°   dip: 82°   rake: -110° Quality: azimuthalGap: -1°   stationPolarityCount: 79   misfitWeightCount: 12.2   misfit: 0.18   stationDistributionRatio: 0.44   meanDistP: 21.9   meanDistT: 27.5   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 231°   dip: 69°   rake: -134° Nodal Plane 2: strike: 120°   dip: 48°   rake: -29° Quality: azimuthalGap: 36°   stationPolarityCount: 79   misfit: 0.33   stationDistributionRatio: 0.49   rmsAngDiffAccPref: 39.33   fracAcc30degPref: 0.50   qualityCode: D Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (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/_amp_aref
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (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/_amp_mwp

Event ID: smi:KOERI/ee/event/1765219278082
Event info last updated: 2025.12.08-19:41:31 UTC
Event first association/location: 2025.12.08-18:54:03 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI