M4.6 earthquake 23 km NNW of Rioblanco, Tolima Department, Colombia
A magnitude 4.6 earthquake struck 23 km NNW of Rioblanco, Tolima Department, Colombia at 11:46 local time (16:46 UTC) on 24 Sept 2026, at a depth of 10 km, according to USGS and GFZ.
Reported by 2 agencies · revised from M4.7
Data: USGS, GFZ · updated 2026-10-04 19:26 UTC · reviewed
- Magnitude
- 4.6light
body-wave magnitude (mb)
revised from 4.7 - Depth
- 10 km
- Status
- Reviewed
- Origin time
- 2026-09-24 16:46:31 UTC
- Local: 24 Sept 2026, 11:46:31 (America/Bogota)
- Epicentre
- 3.711° N, 75.749° 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 |
|---|---|---|
| RioblancoTolima Department, Colombia · pop. 19,090 | 23 km | IVLight |
| ChaparralTolima Department, Colombia · pop. 19,982 | 30 km | IVLight |
| PlanadasTolima Department, Colombia · pop. 21,557 | 58 km | IIIWeak |
| El CerritoValle del Cauca Department, Colombia · pop. 38,390 | 62 km | IIIWeak |
| PraderaValle del Cauca Department, Colombia · pop. 44,630 | 63 km | IIIWeak |
| PalmiraValle del Cauca Department, Colombia · pop. 312,519 | 64 km | IIIWeak |
| CaliValle del Cauca Department, Colombia · pop. 2,392,877 | 91 km | IIWeak |
| ArmeniaQuindío Department, Colombia · pop. 304,314 | 93 km | IIWeak |
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 82 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.
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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 120 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 10 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.
M4.6 releases about 32× the energy of M3.6, and its waves are about 10× taller on a seismogram. Energy: 120 t of TNT vs 3.8 t of TNT.
Each square is the energy of one M3.6. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
5 later earthquakes within 30 km; the largest was M4.5 5 days ago. 7 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M4.6
5 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 0.47 | 4.2 | 10 |
| 11.18 | 4.2 | 10 |
| 14.55 | 4.5 | 57 |
| 87.89 | 4.3 | 10 |
| 125.07 | 4.5 | 10 |
- 4.515 km SW of San Antonio, Tolima Department, Colombia09-29 21:50
- 4.526 km NNW of Rioblanco, Tolima Department, Colombia09-25 07:19
- 4.327 km WNW of Chaparral, Tolima Department, Colombia09-28 08:39
- 4.229 km WSW of Roncesvalles, Tolima Department, Colombia09-24 17:14
- 4.219 km WNW of Chaparral, Tolima Department, Colombia09-25 03:57
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 gfz2026stha. First recorded here 28 Sept 2026, 17:32:06 UTC. Solutions: GFZ (geofon:gfz2026stha); USGS (usgs:us6000txdb). Cite as: SeismoAtlas, “M4.6 earthquake 23 km NNW of Rioblanco, Tolima Department, Colombia”, https://seismoatlas.com/earthquake/gfz2026stha-m4-6-earthquake-23-km-nnw-of-rioblanco-tolima-department-colombia, data from USGS, GFZ.
JSON: /api/v1/events/gfz2026stha. SeismoAtlas is not an official warning service.