QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Trinidad, CO

No earthquake was likely felt in Trinidad in the 24 hours to 6:36 am MST (13:36 UTC). The last one was M 3.4, 45 km (28 mi) WSW, at 3:34 am MST on 8 November 2026, estimated intensity III (weak) in town; 2 felt reports to USGS. Every earthquake near Trinidad

This page: a magnitude 1.5 earthquake was recorded 25 km (15 mi) west of Trinidad, CO, at 8:59 am MDT on 16 April 2023 (14:59 UTC), 5.0 km deep.

USGS: 6 km NNW of Segundo, Colorado

8:59 am MDT, Apr 16, 2023 · · 5.0 km deep · released about 5.4 lb of TNT

10 km30 km60 km120 km N Huerfano County 58 kmCostilla County 58 kmColfax County 65 kmLas Animas County 67 kmAlamosa County 99 kmTaos County 102 kmPueblo County 112 kmCuster County 115 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
8:59 am MDT on 16 April 2023 ()
Where
25 km (15 mi) west of Trinidad, CO · earthquakes near Trinidad
Magnitude
M 1.5 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Huerfano County, 58 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1227 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Trinidad, 25 km away, the estimate is intensity II (weak). 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 16,000 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 · 15 km SSE of this epicentre
  2. 5.0 20 km S of Weston, Colorado · 27 km S 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 37.1848, -104.7791. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Huerfano County, CO 58 km (36 mi) NNW earthquakes near Huerfano County
Costilla County, CO 58 km (36 mi) W earthquakes near Costilla County
Colfax County, NM 65 km (40 mi) S earthquakes near Colfax County
Las Animas County, CO 67 km (41 mi) ENE earthquakes near Las Animas County
Alamosa County, CO 99 km (61 mi) WNW earthquakes near Alamosa County
Taos County, NM 102 km (63 mi) SW earthquakes near Taos County

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

Aftershocks so far

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

  1. 2.2 13 km NNW of Weston, Colorado
  2. 1.7 12 km SSE of Stonewall Gap, Colorado
  3. 2.3 30 km NNE of Ute Park, New Mexico
  4. 1.8 18 km S of Weston, Colorado
  5. 1.6 25 km WSW of Raton, New Mexico
  6. 1.9 2 km S of Valdez, Colorado
  7. 1.7 5 km ENE of El Moro, Colorado
  8. 2.0 7 km NNW of El Moro, Colorado
  9. 1.6 9 km SSE of Stonewall Gap, Colorado
  10. 1.7 15 km S of Weston, Colorado
  11. 1.7 7 km NNW of El Moro, Colorado
  12. 2.4 Colorado
  13. 2.6 6 km NNW of El Moro, Colorado
  14. 2.8 12 km SW of Weston, Colorado
  15. 2.1 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.