M4.3 earthquake 41 km SSW of Posorja, Guayas, Ecuador
A magnitude 4.3 earthquake struck 41 km SSW of Posorja, Guayas, Ecuador at 03:57 local time (08:57 UTC) on 4 Oct 2026, at a depth of 43 km, according to USGS.
Data: USGS · updated 2026-10-04 09:14 UTC · reviewed
- Magnitude
- 4.3light
body-wave magnitude (mb) - Depth
- 42.9 km
- Status
- Reviewed
- Origin time
- 2026-10-04 08:57:21 UTC
- Local: 4 Oct 2026, 03:57:21 (America/Guayaquil)
- Epicentre
- 3.071° S, 80.326° W
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Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map
Nearby places
| Place | Distance | Est. shaking |
|---|---|---|
| PosorjaGuayas, Ecuador · pop. 30,886 | 41 km | IIIWeak |
| Puerto BolívarEl Oro, Ecuador · pop. 8,300 | 42 km | IIWeak |
| MachalaEl Oro, Ecuador · pop. 289,141 | 46 km | IIWeak |
| HuaquillasEl Oro, Ecuador · pop. 39,757 | 47 km | IIWeak |
| PlayasGuayas, Ecuador · pop. 30,564 | 50 km | IIWeak |
| GuayaquilGuayas, Ecuador · pop. 2,723,665 | 108 km | IIWeak |
| Eloy AlfaroGuayas, Ecuador · pop. 315,724 | 114 km | IIWeak |
| CuencaAzuay, Ecuador · pop. 636,996 | 148 km | INot felt |
Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 42 km.
Every agency's solution
Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS, which has been reviewed by an analyst.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| USGSheadlineUSGS NEIC via U.S. Geological Survey | 4.3 mb | 42.9 km | 3.07° S, 80.33° W | – | Reviewed |
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How big was it?
Widely felt near the epicentre: rattling windows and objects. Significant damage is unlikely.
It released roughly the energy of 43 t of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 43 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.
M4.3 releases about 32× the energy of M3.3, and its waves are about 10× taller on a seismogram. Energy: 43 t of TNT vs 1.3 t of TNT.
Each square is the energy of one M3.3. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
No later earthquakes have been recorded within 30 km so far. Aftershock rates usually fall off roughly in proportion to 1/time.
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Reports on SeismoAtlas
No reports yet.
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Event id us6000tzhy. First recorded here 4 Oct 2026, 09:16:03 UTC. Solutions: USGS (usgs:us6000tzhy). Cite as: SeismoAtlas, “M4.3 earthquake 41 km SSW of Posorja, Guayas, Ecuador”, https://seismoatlas.com/earthquake/us6000tzhy-m4-3-earthquake-41-km-ssw-of-posorja-guayas-ecuador, data from USGS.
JSON: /api/v1/events/us6000tzhy. SeismoAtlas is not an official warning service.