QuakeIndex

rock burst · reviewed by a seismologist

M 1.5ml

Earthquake near Paonia, CO

No earthquake was likely felt in Paonia in the 24 hours to 4:55 pm MST (23:55 UTC). The last one was M 3.7, 311 km (193 mi) SE, at 1:55 am MDT on 1 November 2026, estimated intensity II (weak) in town; 6 felt reports to USGS. Every earthquake near Paonia

No: USGS classifies this as a rock burst, not an earthquake. A magnitude 1.5 rock burst was recorded 13 km (8 mi) east-northeast of Paonia, CO, at 6:18 am MDT on 26 July 2021 (12:18 UTC), 1.0 km deep.

USGS: 13 km ENE of Paonia, Colorado

6:18 am MDT, Jul 26, 2021 · · 1.0 km deep · released about 5.4 lb of TNT

10 km30 km60 km120 km N Delta County 37 kmGunnison County 42 kmPitkin County 58 kmOuray County 88 kmGarfield County 88 kmMesa County 89 kmMontrose County 90 kmLake County 101 kmChaffee County 101 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
6:18 am MDT on 26 July 2021 ()
Where
13 km (8 mi) east-northeast of Paonia, CO · earthquakes near Paonia
Magnitude
M 1.5 (ml)
Depth
1.0 km below the surface
Felt
no reports yet
Nearest
Delta County, 37 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1866 days ago

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 10 km (6 mi) from the epicentre. In Paonia, 13 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.

USGS catalogues this as rock burst, not an earthquake.

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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 38.8968, -107.4448. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Delta County, CO 37 km (23 mi) W earthquakes near Delta County
Gunnison County, CO 42 km (26 mi) SE earthquakes near Gunnison County
Pitkin County, CO 58 km (36 mi) NE earthquakes near Pitkin County
Ouray County, CO 88 km (55 mi) SSW earthquakes near Ouray County
Garfield County, CO 88 km (55 mi) NNW earthquakes near Garfield County
Mesa County, CO 89 km (55 mi) W earthquakes near Mesa County

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

Aftershocks so far

1 earthquake has been recorded within 50 km since this one.

  1. 2.8 10 km NE of Redstone, 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.