QuakeIndex

Earthquake · reviewed by a seismologist

M 4.1mwr

Colorado

Yes. A magnitude 4.1 earthquake was recorded in Colorado, at 8:18 am MDT on 19 June 2023 (14:18 UTC), 6.0 km deep. 56 people have reported feeling it to USGS.

· 6.0 km deep · released about 21 tons of TNT

10 km30 km60 km120 km N Las Animas County 38 kmHuerfano County 60 kmColfax County 79 kmCostilla County 84 kmOtero County 92 kmPueblo County 95 kmCuster County 118 kmAlamosa County 119 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 4.1 (mwr)
Depth
6.0 km below the surface
Felt
56 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Las Animas County, 38 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1173 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 491 km (305 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.

Likely felt in: Trinidad 16 km, intensity IV · Walsenburg 44 km, intensity IV · Raton 46 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 21 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 7,900× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 350× the energy of this one
  3. Magna, Utah 2020 M 5.7 250× the energy of this one
  4. This earthquake M 4.1 about 21 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 45× 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 2 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.3 6 km S of Valdez, Colorado · 34 km SW 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 37.3123, -104.4787. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Las Animas County, CO 38 km (24 mi) E earthquakes near Las Animas County
Huerfano County, CO 60 km (37 mi) NW earthquakes near Huerfano County
Colfax County, NM 79 km (49 mi) S earthquakes near Colfax County
Costilla County, CO 84 km (52 mi) W earthquakes near Costilla County
Otero County, CO 92 km (57 mi) NE earthquakes near Otero County
Pueblo County, CO 95 km (59 mi) N earthquakes near Pueblo County

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

Aftershocks so far

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

  1. 2.6 12 km SSE of Walsenburg, Colorado
  2. 1.5 7 km N of El Moro, Colorado
  3. 1.5 Colorado
  4. 3.0 Colorado
  5. 3.2 9 km N of Segundo, Colorado
  6. 2.3 7 km N of Segundo, Colorado
  7. 2.2 7 km NNW of El Moro, Colorado
  8. 2.2 13 km NNW of Weston, Colorado
  9. 1.9 2 km S of Valdez, Colorado
  10. 1.7 5 km ENE of El Moro, Colorado
  11. 2.0 7 km NNW of El Moro, Colorado
  12. 1.7 15 km S of Weston, Colorado
  13. 1.7 7 km NNW of El Moro, Colorado
  14. 2.4 Colorado
  15. 2.6 6 km NNW of El Moro, 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.