QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

5 km NE of Greeley, Colorado

· 8.1 km deep · released about 43 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Weld County 27 kmBroomfield County 65 kmAdams County 72 kmLarimer County 72 kmBoulder County 74 kmMorgan County 76 kmDenver County 80 kmLaramie County 92 kmArapahoe County 95 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 2.1 (ml)
Depth
8.1 km below the surface
Felt
no reports yet
Nearest
Weld County, 27 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3127 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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.

Where

Epicentre 40.4625, -104.6732. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Weld County, CO 27 km (17 mi) WSW of here earthquakes near Weld County
Broomfield County, CO 65 km (40 mi) NNE of here earthquakes near Broomfield County
Adams County, CO 72 km (44 mi) NNW of here earthquakes near Adams County
Larimer County, CO 72 km (45 mi) ESE of here earthquakes near Larimer County
Boulder County, CO 74 km (46 mi) NE of here earthquakes near Boulder County
Morgan County, CO 76 km (47 mi) WNW of here earthquakes near Morgan County

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

Aftershocks so far

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

  1. 2.3 2 km SW of Gilcrest, Colorado
  2. 2.3 4 km ENE of Greeley, Colorado
  3. 1.9 8 km ENE of Greeley, Colorado
  4. 2.9 7 km NE of Greeley, Colorado
  5. 2.3 8 km ENE of Greeley, Colorado
  6. 1.7 7 km ENE of Greeley, Colorado
  7. 2.3 8 km ENE of Greeley, 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.