Early-est:     Northern Sumatra, Indonesia    2025.01.31-11:03:46.04    q:A      mb:5.4    Mwp:5.7    Mwpd:-    Td*T50Ex:1.0     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: 5.4 [186]    Mwp: 5.7 [45]    Mwpd: 6.0Xinv [38] Region: Northern Sumatra, Indonesia Origin Time: 2025.01.31-11:03:46.04 UTC Hypocenter: lat: 3.38°  lon: 97.07°  [+/-17km]    depth: 80km  [+/-19km] Location Quality: qualityCode:  A     stdErr: 1.0s   assocPhases: 338   usedPhases: 258 minDist: 6.3°   maxDist: 172.2°   AzGap: 13°   2ndAzGap: 26°   atten: -1.06 [+/-0.22] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 11km   maxHorUnc: 17km   azMaxHorUnc: 11° 68%ConfEllipsoid:   semiMajorAxisLength: 22km   majorAxisAzimuth: 190°   majorAxisPlunge: 32°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 20°   intermediateAxisPlunge: 58°   semiMinorAxisLength: 14km Tsunamigeneic Assesment: Discriminants: Prob Underwater: 94% T50Ex: 0.6 [177]    Td: 1.8s [11]    Td*T50Ex: 1.0 [11]    To: 38.1s [167] Closest plate boundaries:    Sunda - Burma [continental rift boundary]: distance: ~60km    Burma / Australia [subduction zone]: distance: ~240km    Sunda / Australia [subduction zone]: distance: ~250km Subduction geometry:    Zone: Sumatra-Java    Slab depth at epicenter: 70km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (240km)  no  no Prob underwater:  94%  94%  94% Td*T50Ex:    1.0    1.0    1.0 Td*To:      68.6      68.6      68.6 Mwp magnitude:        5.7        5.7        5.7 Hypocenter depth:        80km        80km        80km Slab depth at epicenter:        70km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY): Nodal Plane 1: strike: 26°   dip: 48°   rake: -144° Nodal Plane 2: strike: 270°   dip: 64°   rake: -48° Quality: azimuthalGap: -1°   stationPolarityCount: 236   misfitWeightCount: 44.4   misfit: 0.21   stationDistributionRatio: 0.49   meanDistP: 23.0   meanDistT: 25.5   qualityCode: B 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: 102°   dip: 25°   rake: -90° Nodal Plane 2: strike: 282°   dip: 65°   rake: -90° Quality: azimuthalGap: 25°   stationPolarityCount: 236   misfit: 0.24   stationDistributionRatio: 0.63   rmsAngDiffAccPref: 31.87   fracAcc30degPref: 0.64   qualityCode: C Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 69°   dip: 19°   rake: -104° Nodal Plane 2: strike: 264°   dip: 72°   rake: -85° Quality: azimuthalGap: -1°   stationPolarityCount: 81   misfitWeightCount: 15.0   misfit: 9999.90   stationDistributionRatio: 0.68   meanDistP: 23.1   meanDistT: 30.1   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_aref
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 23°   dip: 35°   rake: -154° Nodal Plane 2: strike: 271°   dip: 75°   rake: -58° Quality: azimuthalGap: -1°   stationPolarityCount: 40   misfitWeightCount: 7.7   misfit: 9999.90   stationDistributionRatio: 0.51   meanDistP: 24.5   meanDistT: 26.5   qualityCode: C Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_mwp

Event ID: smi:KOERI/ee/event/1738321427796
Event info last updated: 2025.01.31-12:04:15 UTC
Event first association/location: 2025.01.31-11:08:25 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI