Early-est: Andreanof Islands, Aleutian Is. 2025.12.15-18:03:52.86 q:B mb:5.0 Mwp:- Mwpd:- Td*T50Ex:- 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: 5.0 [58] Mwp: - [0] Mwpd: - [0]
Region:	Andreanof Islands, Aleutian Is.
Origin Time:	2025.12.15-18:03:52.86 UTC
Hypocenter:	lat: 51.34° lon: -176.32° [+/-15km] depth: 18km [+/-15km]
Location Quality:	qualityCode: B stdErr: 1.7s assocPhases: 104 usedPhases: 72 minDist: 3.2° maxDist: 155.5° AzGap: 95° 2ndAzGap: 112° atten: -1.26 [+/-0.18]
Location Uncertainty:	68%ConfEllipse: minHorUnc: 13km maxHorUnc: 15km azMaxHorUnc: 9° 68%ConfEllipsoid: semiMajorAxisLength: 19km majorAxisAzimuth: 10° majorAxisPlunge: 13° semiIntermediateAxisLength: 16km intermediateAxisAzimuth: 103° intermediateAxisPlunge: 12° semiMinorAxisLength: 15km

Tsunamigeneic Assesment:

Discriminants:

Prob Underwater: >99%
T50Ex: 0.4 [36]    Td: 1.6Xs [2]    Td*T50Ex: - [0]    To: 1.9s [28]
Closest plate boundaries:
   North America / Pacific [subduction zone]: distance: ~80km
Subduction geometry:    Zone: Alaska-Aleutians    Slab depth at epicenter: 32km

Decision table (TEST!):

Event type:

Subduction Zone

Other Thrust/Normal

Strike-slip

Compatible close plate boundary?:

YES (80km)

Prob underwater:

>99%

Td*T50Ex:

Td*To:

Mwp magnitude:

Hypocenter depth:

18km

Slab depth at epicenter:

32km

First-motion Focal Mechanism (FMAMP_POLARITY): (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1:	strike: 45° dip: 46° rake: -64°
Nodal Plane 2:	strike: 189° dip: 50° rake: -115°
Quality:	azimuthalGap: -1° stationPolarityCount: 68 misfitWeightCount: 10.7 misfit: 0.25 stationDistributionRatio: 0.53 meanDistP: 29.6 meanDistT: 38.6 qualityCode: C
Method:	methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity

./hypo.1765821836512.mech.fmamp_polarity.mechanism.jpg

First-motion Focal Mechanism (HASH): (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1:	strike: 199° dip: 78° rake: 164°
Nodal Plane 2:	strike: 292° dip: 74° rake: 12°
Quality:	azimuthalGap: 94° stationPolarityCount: 68 misfit: 0.36 stationDistributionRatio: 0.58 rmsAngDiffAccPref: 30.49 fracAcc30degPref: 0.86 qualityCode: C
Method:	methodID: smi:gov.usgs/focalmec/HASH_1.2

./hypo.1765821836512.mech.hash.mechanism.jpg

First-motion Focal Mechanism (FMAMP_AMP_AREF): (No solution available)
Nodal Plane 1:	strike: 0° dip: 0° rake: nan°
Nodal Plane 2:	strike: nan° dip: nan° rake: nan°
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

./hypo.1765821836512.mech.fmamp_amp_aref.mechanism.jpg

First-motion Focal Mechanism (FMAMP_AMP_MWP): (No solution available)
Nodal Plane 1:	strike: 0° dip: 0° rake: nan°
Nodal Plane 2:	strike: nan° dip: nan° rake: nan°
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

./hypo.1765821836512.mech.fmamp_amp_mwp.mechanism.jpg

Event ID: smi:KOERI/ee/event/1765821836512
Event info last updated: 2025.12.15-19:04:02 UTC
Event first association/location: 2025.12.15-18:11:17 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI

Early-est: Andreanof Islands, Aleutian Is. 2025.12.15-18:03:52.86 q:B mb:5.0 Mwp:- Mwpd:- Td*T50Ex:- 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!

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