Early-est:     Mariana Islands Region    2025.01.28-18:03:47.76    q:A      mb:4.5    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: 4.5 [43]    Mwp: - [0]    Mwpd: - [0] Region: Mariana Islands Region Origin Time: 2025.01.28-18:03:47.76 UTC Hypocenter: lat: 21.49°  lon: 143.31°  [+/-16km]    depth: 285km  [+/-16km] Location Quality: qualityCode:  A     stdErr: 1.0s   assocPhases: 77   usedPhases: 56 minDist: 5.7°   maxDist: 149.9°   AzGap: 34°   2ndAzGap: 59°   atten: -1.50 [+/-0.21] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 12km   maxHorUnc: 16km   azMaxHorUnc: 92° 68%ConfEllipsoid:   semiMajorAxisLength: 20km   majorAxisAzimuth: 92°   majorAxisPlunge: 0°   semiIntermediateAxisLength: 16km   intermediateAxisAzimuth: 1°   intermediateAxisPlunge: 79°   semiMinorAxisLength: 15km Tsunamigeneic Assesment: Discriminants: Prob Underwater: >99% T50Ex: 0.3 [27]    Td: -s [0]    Td*T50Ex: - [0]    To: 1.3s [18] Closest plate boundaries:    Philippine Sea - Mariana [oceanic spreading ridge]: distance: ~20km    Mariana / Pacific [subduction zone]: distance: ~240km    Philippine Sea / Pacific [subduction zone]: distance: ~320km Subduction geometry:    Zone: Izu-Bonin    Slab depth at epicenter: 236km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (240km)  no  no Prob underwater:  >99%  >99%  >99% Td*T50Ex:    -    -    - Td*To:      -      -      - Mwp magnitude:        -        -        - Hypocenter depth:        285km        285km        285km Slab depth at epicenter:        236km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 3°   dip: 38°   rake: -44° Nodal Plane 2: strike: 131°   dip: 65°   rake: -119° Quality: azimuthalGap: -1°   stationPolarityCount: 47   misfitWeightCount: 12.7   misfit: 0.19   stationDistributionRatio: 0.64   meanDistP: 24.8   meanDistT: 43.9   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
First-motion Focal Mechanism (HASH):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 356°   dip: 35°   rake: -58° Nodal Plane 2: strike: 138°   dip: 61°   rake: -111° Quality: azimuthalGap: 33°   stationPolarityCount: 47   misfit: 0.31   stationDistributionRatio: 0.68   rmsAngDiffAccPref: 30.79   fracAcc30degPref: 0.62   qualityCode: C 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/1738087429387
Event info last updated: 2025.01.28-19:04:03 UTC
Event first association/location: 2025.01.28-18:08:49 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI