Early-est:     Northern Sumatra, Indonesia    2025.12.09-07:02:58.71    q:B      mb:5.1    Mwp:5.6    Mwpd:-    Td*T50Ex:1.4     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: 5.1 [59]    Mwp: 5.6 [11]    Mwpd: 6.0Xinv [5] Region: Northern Sumatra, Indonesia Origin Time: 2025.12.09-07:02:58.71 UTC Hypocenter: lat: 2.71°  lon: 96.05°  [+/-18km]    depth: 34km  [+/-26km] Location Quality: qualityCode:  B     stdErr: 1.1s   assocPhases: 103   usedPhases: 76 minDist: 2.9°   maxDist: 148.7°   AzGap: 73°   2ndAzGap: 74°   atten: -1.10 [+/-0.21] Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 18km   azMaxHorUnc: 57° 68%ConfEllipsoid:   semiMajorAxisLength: 30km   majorAxisAzimuth: 51°   majorAxisPlunge: 53°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 284°   intermediateAxisPlunge: 24°   semiMinorAxisLength: 15km Tsunamigeneic Assesment: Discriminants: Prob Underwater: 27% T50Ex: 0.6 [38]    Td: 2.5s [12]    Td*T50Ex: 1.4 [12]    To: 29.4s [29] Closest plate boundaries:    Sunda - Burma [continental rift boundary]: distance: ~80km    Burma / Australia [subduction zone]: distance: ~110km    India - Australia [oceanic convergent boundary]: distance: ~140km    Burma / India [subduction zone]: distance: ~140km    Sunda / Australia [subduction zone]: distance: ~150km    India \ Burma [subduction zone]: distance: ~630km Subduction geometry:    Zone: Sumatra-Java    Slab depth at epicenter: 22km Decision table (TEST!): Event type: Subduction Zone Other Thrust/Normal Strike-slip Compatible close plate boundary?:  YES (110km)  no  no Prob underwater:  27%  27%  27% Td*T50Ex:    1.4    1.4    1.4 Td*To:      73.5      73.5      73.5 Mwp magnitude:        5.6        5.6        5.6 Hypocenter depth:        34km        34km        34km Slab depth at epicenter:        22km        -        -

First-motion Focal Mechanism (FMAMP_POLARITY):    (Warning: Unreliable solution, qualityCode=C) Nodal Plane 1: strike: 266°   dip: 11°   rake: 49° Nodal Plane 2: strike: 128°   dip: 82°   rake: 97° Quality: azimuthalGap: -1°   stationPolarityCount: 58   misfitWeightCount: 13.8   misfit: 0.10   stationDistributionRatio: 0.59   meanDistP: 35.2   meanDistT: 17.9   qualityCode: C 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: 214°   dip: 23°   rake: 14° Nodal Plane 2: strike: 111°   dip: 85°   rake: 112° Quality: azimuthalGap: 72°   stationPolarityCount: 58   misfit: 0.20   stationDistributionRatio: 0.66   rmsAngDiffAccPref: 26.79   fracAcc30degPref: 0.85   qualityCode: C Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
First-motion Focal Mechanism (FMAMP_AMP_AREF):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 44°   dip: 19°   rake: 145° Nodal Plane 2: strike: 167°   dip: 79°   rake: 74° Quality: azimuthalGap: -1°   stationPolarityCount: 16   misfitWeightCount: 3.8   misfit: 9999.90   stationDistributionRatio: 0.82   meanDistP: 42.3   meanDistT: 31.0   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_aref
First-motion Focal Mechanism (FMAMP_AMP_MWP):    (Warning: VERY UNRELIABLE SOLUTION, qualityCode=D) Nodal Plane 1: strike: 249°   dip: 39°   rake: 49° Nodal Plane 2: strike: 117°   dip: 61°   rake: 118° Quality: azimuthalGap: -1°   stationPolarityCount: 9   misfitWeightCount: 4.9   misfit: 9999.90   stationDistributionRatio: 0.40   meanDistP: 47.3   meanDistT: 27.8   qualityCode: D Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_amp_mwp

Event ID: smi:KOERI/ee/event/1765263775305
Event info last updated: 2025.12.09-08:03:03 UTC
Event first association/location: 2025.12.09-07:10:20 UTC
Software: Early-est 1.2.0 (2016.06.27)
Agency: KOERI