Earthquake · reviewed by a seismologist
M 1.7ml
Earthquake near Trinidad, CO
No earthquake was likely felt in Trinidad in the 24 hours to 7:09 am MST (14:09 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 1.7 earthquake was recorded 38 km (23 mi) southwest of Trinidad, CO, at 2:15 pm MDT on 21 August 2023 (20:15 UTC), 5.0 km deep.
USGS: 18 km S of Weston, Colorado
- When
- 2:15 pm MDT on 21 August 2023 ()
- Where
- 38 km (23 mi) southwest of Trinidad, CO · earthquakes near Trinidad
- Magnitude
- M 1.7 (ml)
- Depth
- 5.0 km below the surface
- Felt
- no reports yet
- Nearest
- Colfax County, 43 km SSE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1110 days ago
Earthquake alerts for Trinidad, CO
Get a notification in this browser when USGS records an earthquake near Trinidad, CO. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 mi) from the epicentre. In Trinidad, 38 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 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
- Around the size people start to feel M 3.0 89× the energy of this one
- This earthquake M 1.7 about 11 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 7,900 times the energy of this one.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 5.3 6 km S of Valdez, Colorado · 16 km NE of this epicentre
- 5.0 20 km S of Weston, Colorado · 2 km SSE 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 36.9662, -104.8414. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Colfax County, NM | 43 km (27 mi) | SSE | earthquakes near Colfax County |
| Costilla County, CO | 63 km (39 mi) | NW | earthquakes near Costilla County |
| Las Animas County, CO | 81 km (50 mi) | ENE | earthquakes near Las Animas County |
| Huerfano County, CO | 81 km (50 mi) | N | earthquakes near Huerfano County |
| Taos County, NM | 83 km (52 mi) | WSW | earthquakes near Taos County |
| Alamosa County, CO | 107 km (67 mi) | NW | earthquakes near Alamosa 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.
- 2.1 26 km S of Weston, Colorado
- 1.8 25 km S of Weston, Colorado
- 2.0 26 km SSW of Segundo, Colorado
- 2.1 26 km SSW of Segundo, Colorado
- 1.6 18 km S of Weston, Colorado
- 2.0 17 km S of Weston, Colorado
- 2.0 16 km SW of Weston, Colorado
- 1.5 34 km NNE of Cimarron, New Mexico
- 2.8 9 km NNW of El Moro, Colorado
- 1.7 11 km NE of Stonewall Gap, Colorado
- 1.7 6 km WNW of Hoehne, Colorado
- 1.5 13 km S of Stonewall Gap, Colorado
- 1.5 15 km SSW of Weston, Colorado
- 1.9 23 km S of Weston, Colorado
- 1.6 12 km S 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.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.