QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

Earthquake near Aspen, CO

No earthquake was likely felt in Aspen in the 24 hours to 7:46 am MST (14:46 UTC). The last one was M 3.7, 293 km (182 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 Aspen

This page: a magnitude 2.8 earthquake was recorded 11 km (7 mi) north-northeast of Aspen, CO, at 9:02 pm MDT on 10 April 2021 (03:02 UTC), 2.4 km deep. 23 people have reported feeling it to USGS.

USGS: 9 km E of Woody Creek, Colorado

9:02 pm MDT, Apr 10, 2021 · · 2.4 km deep · released about 480 lb of TNT

10 km30 km60 km120 km N Pitkin County 14 kmLake County 38 kmEagle County 39 kmSummit County 66 kmGunnison County 73 kmChaffee County 74 kmPark County 93 kmGarfield County 103 kmClear Creek County 105 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
9:02 pm MDT on 10 April 2021 ()
Where
11 km (7 mi) north-northeast of Aspen, CO · earthquakes near Aspen
Magnitude
M 2.8 (ml)
Depth
2.4 km below the surface
Felt
23 reports · strongest reported intensity III
Nearest
Pitkin County, 14 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1971 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 27 km (17 mi) from the epicentre. In Aspen, 11 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.

Earthquakes near other towns within 30 km: Snowmass Village, Basalt, El Jebel.

How big was it?

This earthquake released about 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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 39.2863, -106.7754. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pitkin County, CO 14 km (9 mi) WSW earthquakes near Pitkin County
Lake County, CO 38 km (23 mi) ESE earthquakes near Lake County
Eagle County, CO 39 km (24 mi) N earthquakes near Eagle County
Summit County, CO 66 km (41 mi) NE earthquakes near Summit County
Gunnison County, CO 73 km (45 mi) SSW earthquakes near Gunnison County
Chaffee County, CO 74 km (46 mi) SE earthquakes near Chaffee County

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

Aftershocks so far

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

  1. 2.8 10 km NE of Redstone, Colorado
  2. 2.6 12 km S of Mulford, Colorado
  3. 1.9 6 km WNW of Snowmass Village, Colorado
  4. 2.5 6 km NNW of Gypsum, Colorado
  5. 1.8 2 km NNW of El Jebel, 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.