QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

18 km S of Stonewall Gap, Colorado

Yes. A magnitude 2.8 earthquake was recorded 18 km S of Stonewall Gap, Colorado, at 11:22 am MDT on 17 May 2023 (17:22 UTC), 5.0 km deep.

· 5.0 km deep · released about 480 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Costilla County 48 kmColfax County 54 kmTaos County 71 kmHuerfano County 78 kmAlamosa County 93 kmLas Animas County 95 kmConejos County 105 kmMora 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 2.8 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Costilla County, 48 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1028 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 27 km (17 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.3 on 2023-03-10 — about 180 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.3 6 km S of Valdez, Colorado · 30 km ENE of this epicentre
  2. 5.0 20 km S of Weston, Colorado · 18 km ESE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 36.9858, -105.0295. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Costilla County, CO 48 km (30 mi) NW earthquakes near Costilla County
Colfax County, NM 54 km (34 mi) SE earthquakes near Colfax County
Taos County, NM 71 km (44 mi) SW earthquakes near Taos County
Huerfano County, CO 78 km (49 mi) N earthquakes near Huerfano County
Alamosa County, CO 93 km (58 mi) NW earthquakes near Alamosa County
Las Animas County, CO 95 km (59 mi) ENE earthquakes near Las Animas County

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

Aftershocks so far

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

  1. 2.1 14 km S of Stonewall Gap, Colorado
  2. 1.8 13 km SSE of Stonewall Gap, Colorado
  3. 1.7 17 km SSE of Stonewall Gap, Colorado
  4. 4.0 19 km SSW of Weston, Colorado
  5. 3.3 Colorado
  6. 1.7 18 km S of Weston, Colorado
  7. 3.0 Colorado
  8. 3.2 9 km N of Segundo, Colorado
  9. 1.5 New Mexico
  10. 1.9 23 km S of Segundo, Colorado
  11. 1.9 24 km SSW of Segundo, Colorado
  12. 1.5 New Mexico
  13. 1.6 23 km SSW of Segundo, Colorado
  14. 1.6 New Mexico
  15. 1.6 23 km SSW of Segundo, 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.

On USGS

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