QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

17 km S of Weston, Colorado

· 5.0 km deep · released about 43 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Colfax County 45 kmCostilla County 59 kmHuerfano County 80 kmTaos County 81 kmLas Animas County 83 kmAlamosa County 104 kmMora County 110 kmConejos County 118 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 2.1 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Colfax County, 45 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 128 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 lb of TNT

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 36.9736, -104.8766. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Colfax County, NM 45 km (28 mi) NNW of here earthquakes near Colfax County
Costilla County, CO 59 km (37 mi) SE of here earthquakes near Costilla County
Huerfano County, CO 80 km (50 mi) S of here earthquakes near Huerfano County
Taos County, NM 81 km (50 mi) ENE of here earthquakes near Taos County
Las Animas County, CO 83 km (52 mi) WSW of here earthquakes near Las Animas County
Alamosa County, CO 104 km (65 mi) SE of here earthquakes near Alamosa County

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

Aftershocks so far

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

  1. 3.7 32 km SSW of Segundo, Colorado
  2. 3.8 34 km SSW of Segundo, Colorado
  3. 2.0 22 km S of Weston, Colorado
  4. 2.8 14 km S of Stonewall Gap, Colorado
  5. 2.2 16 km SSE of Stonewall Gap, Colorado
  6. 2.4 15 km S of Stonewall Gap, Colorado
  7. 3.1 18 km SSW of Weston, Colorado
  8. 1.7 17 km SSW of Weston, Colorado
  9. 1.5 21 km SSW of Weston, Colorado
  10. 1.5 18 km SSW of Weston, Colorado
  11. 1.7 19 km SSE of Stonewall Gap, Colorado
  12. 1.5 20 km SSW of Weston, Colorado
  13. 1.9 15 km SSE of Stonewall Gap, Colorado
  14. 2.9 16 km SSE of Stonewall Gap, Colorado
  15. 2.4 14 km SW of Weston, 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 4.3 on 2023-03-10 — it released about 2,000 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.