QuakeIndex

Earthquake · reviewed by a seismologist

M 3.7mwr

Earthquake near Trinidad, CO

No earthquake was likely felt in Trinidad in the 24 hours to 2:20 am MST (09:20 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 3.7 earthquake was recorded 44 km (27 mi) west-southwest of Trinidad, CO, at 1:55 am MDT on 1 November 2026 (07:55 UTC), 9.2 km deep. 6 people have reported feeling it to USGS.

USGS: 17 km SSW of Weston, Colorado

1:55 am MDT, Nov 1, 2026 · · 9.2 km deep · released about 5.4 tons of TNT

10 km30 km60 km120 km N Colfax County 52 kmCostilla County 52 kmHuerfano County 76 kmTaos County 77 kmLas Animas County 88 kmAlamosa County 97 kmConejos County 111 kmMora County 114 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
1:55 am MDT on 1 November 2026 ()
Where
44 km (27 mi) west-southwest of Trinidad, CO · earthquakes near Trinidad
Magnitude
M 3.7 (mwr)
Depth
9.2 km below the surface
Felt
6 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Colfax County, 52 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 10 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 370 km (230 mi) from the epicentre. In Trinidad, 44 km away, the estimate is intensity III (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.

Likely felt in: Trinidad 44 km, intensity III · Raton 47 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 5.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 32,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,000× the energy of this one
  4. This earthquake M 3.7 about 5.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 11× 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.3 on 2023-03-10 — about 7.9 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 · 23 km ENE of this epicentre
  2. 5.0 20 km S of Weston, Colorado · 12 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 37.0038, -104.9525. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Colfax County, NM 52 km (32 mi) SSE earthquakes near Colfax County
Costilla County, CO 52 km (32 mi) NW earthquakes near Costilla County
Huerfano County, CO 76 km (47 mi) N earthquakes near Huerfano County
Taos County, NM 77 km (48 mi) SW earthquakes near Taos County
Las Animas County, CO 88 km (55 mi) ENE earthquakes near Las Animas County
Alamosa County, CO 97 km (60 mi) NW earthquakes near Alamosa County

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

Aftershocks so far

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

  1. 3.4 8 km SSE of Stonewall Gap, Colorado
  2. 2.1 14 km SSE of Stonewall Gap, Colorado
  3. 2.6 10 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.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
measured intensity4.324.31
felt reports56
felt reports45
reported intensity3.94.1
felt reports34
felt reports23
measured intensity4.384.32
reported intensity23.9
felt reports12
measured intensitynot reported4.38
reported intensitynot reported2
felt reportsnot reported1

On USGS

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