QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5mwr

16 km NNW of Weston, Colorado

· 4.8 km deep · released about 2.7 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Costilla County 45 kmHuerfano County 47 kmColfax County 77 kmLas Animas County 78 kmAlamosa County 84 kmTaos County 100 kmCuster County 101 kmPueblo County 107 kmConejos County 112 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 3.5 (mwr)
Depth
4.8 km below the surface
Felt
16 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Costilla County, 45 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2508 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 16 people have reported feeling it to USGS.

How big was it?

This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,000× the energy of this one
  4. This earthquake M 3.5 about 2.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 5.6× more

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 37.2661, -104.9184. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Costilla County, CO 45 km (28 mi) E of here earthquakes near Costilla County
Huerfano County, CO 47 km (29 mi) S of here earthquakes near Huerfano County
Colfax County, NM 77 km (48 mi) NNW of here earthquakes near Colfax County
Las Animas County, CO 78 km (48 mi) W of here earthquakes near Las Animas County
Alamosa County, CO 84 km (52 mi) ESE of here earthquakes near Alamosa County
Taos County, NM 100 km (62 mi) NE of here earthquakes near Taos County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

58 earthquakes have been recorded within 50 km since this one.

  1. 1.6 3 km S of Walsenburg, Colorado
  2. 2.1 4 km SSW of Walsenburg, Colorado
  3. 1.5 4 km SSW of Walsenburg, Colorado
  4. 1.5 6 km ESE of El Moro, Colorado
  5. 2.5 4 km SSW of Walsenburg, Colorado
  6. 1.8 16 km S of Stonewall Gap, Colorado
  7. 2.0 15 km S of Stonewall Gap, Colorado
  8. 1.6 16 km S of Stonewall Gap, Colorado
  9. 2.7 16 km S of Stonewall Gap, Colorado
  10. 1.7 15 km SSE of Stonewall Gap, Colorado
  11. 1.9 16 km SSE of Stonewall Gap, Colorado
  12. 1.8 14 km SW of Weston, Colorado
  13. 1.5 11 km SSE of Stonewall Gap, Colorado
  14. 1.9 11 km SE of Aguilar, Colorado
  15. 2.8 14 km SSE of Stonewall Gap, Colorado

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 4.0 on 2016-02-06 — it released about 5.6 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.