Early-est:     North of Halmahera, Indonesia    2026.02.13-14:57:03.03    q:A      mb:5.2    Mwp:5.8*    Mwpd:-    Td*T50Ex:2.0     fmamp_polarity:./hypo.1770994624344.mech.fmamp_polarity.thumb.jpg     fmamp_polarity_waveform:./hypo.1770994624344.mech.fmamp_polarity_waveform.thumb.jpg     hash:./hypo.1770994624344.mech.hash.thumb.jpg

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

Earthquake Details:
Magnitude: mb: 5.2 [52]    Mwp: 5.8* [31]    Mwpd: 6.0Xinv [27]
Region: North of Halmahera, Indonesia
Origin Time: 2026.02.13-14:57:03.03 UTC
Hypocenter: lat: 4.21°  lon: 128.30°  [+/-15km]    depth: 30km  [+/-20km]
Location Quality: qualityCode:  A     stdErr: 1.2s   assocPhases: 117   usedPhases: 68
minDist: 3.6°   maxDist: 167.7°   AzGap: 67°   2ndAzGap: 77°   atten: -0.85 [+/-0.24]
Location Uncertainty: 68%ConfEllipse:   minHorUnc: 13km   maxHorUnc: 15km   azMaxHorUnc: 98°
68%ConfEllipsoid:   semiMajorAxisLength: 22km   majorAxisAzimuth: 278°   majorAxisPlunge: 53°   semiIntermediateAxisLength: 17km   intermediateAxisAzimuth: 98°   intermediateAxisPlunge: 37°   semiMinorAxisLength: 16km
Tsunamigeneic Assesment:
Discriminants: Prob Underwater: >99%
T50Ex: 0.6 [49]    Td: 3.5s [24]    Td*T50Ex: 2.0 [24]    To: 30.7s [47]
Closest plate boundaries:
   Philippine Sea \ Sunda [subduction zone]: distance: ~20km
Subduction geometry: none or not available
Decision table (TEST!):
Event type: Subduction Zone Other Thrust/Normal Strike-slip
Compatible close plate boundary?:
 YES (20km)
 no
 no
Prob underwater:
 >99%
 >99%
 >99%
Td*T50Ex:
   2.0
   2.0
   2.0
Td*To:
     107.5
     107.5
     107.5
Mwp magnitude:
       5.8*
       5.8*
       5.8*
Hypocenter depth:
       30km
       30km
       30km
Slab depth at epicenter:
       n/a
       -
       -
Tsunami and Rupture predictions (TEST!): No prediction: Event too small (Mwp<7.0) or too few Mwp readings (N<20)
./hypo.1770994624344.map.jpg

First-motion Focal Mechanism (FMAMP_POLARITY):
Nodal Plane 1: strike: 151°   dip: 10°   rake: 51°
Nodal Plane 2: strike: 10°   dip: 82°   rake: 96°
Quality: azimuthalGap: -1°   stationPolarityCount: 58   misfitWeightCount: 15.4   misfit: 0.14   stationDistributionRatio: 0.45   meanDistP: 29.8   meanDistT: 29.4   qualityCode: B
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity
./hypo.1770994624344.mech.fmamp_polarity.mechanism.jpg
First-motion Focal Mechanism (FMAMP_POLARITY_WAVEFORM):    (Warning: Unreliable solution, qualityCode=C)
Nodal Plane 1: strike: 159°   dip: 14°   rake: 18°
Nodal Plane 2: strike: 52°   dip: 86°   rake: 104°
Quality: azimuthalGap: -1°   stationPolarityCount: 14   misfitWeightCount: 4.2   misfit: 0.00   stationDistributionRatio: 0.77   meanDistP: 43.8   meanDistT: 36.2   qualityCode: C
Method: methodID: smi:net.alomax/focalmec/fmamp_0.0.5X_2016.06.14/_polarity_waveform
./hypo.1770994624344.mech.fmamp_polarity_waveform.mechanism.jpg
First-motion Focal Mechanism (HASH):
Nodal Plane 1: strike: 8°   dip: 82°   rake: 85°
Nodal Plane 2: strike: 222°   dip: 9°   rake: 124°
Quality: azimuthalGap: 77°   stationPolarityCount: 58   misfit: 0.26   stationDistributionRatio: 0.80   rmsAngDiffAccPref: 24.72   fracAcc30degPref: 0.90   qualityCode: B
Method: methodID: smi:gov.usgs/focalmec/HASH_1.2
./hypo.1770994624344.mech.hash.mechanism.jpg

Event ID: smi:alomax.net_BETA/author/ee/event/1770994624344
Event info last updated: 2026.02.13-15:56:01 UTC
Event first association/location: 2026.02.13-15:02:03 UTC
Software: Early-est 1.2.10 (2024.02.23)
Agency: alomax.net_BETA