28 km E of La Sal, Utah

2020-12-20 01:53 UTC · 0.8 km deep · released about 1.4 tons of TNT

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: 2020-12-20 01:53 UTC
Magnitude: M 3.3 (ml)
Depth: 0.8 km below the surface
Felt: 5 reports · strongest reported intensity II
Nearest: San Miguel County, 52 km SE
Status: Reviewed by a seismologist

USGS · last changed by USGS 2038 days ago · we first saw it 2038 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 5 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

Northridge, California 1994 M 6.7 120,000× the energy of this one
Mineral, Virginia 2011 M 5.8 5,400× the energy of this one
Magna, Utah 2020 M 5.7 3,800× the energy of this one
This earthquake M 3.3 about 1.4 tons of TNT
Around the size people start to feel M 3.0 this one released 2.9× 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.

Where

Map loads when it scrolls into view

Epicentre 38.2767, -108.9220. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
San Miguel County, CO	52 km (33 mi)	NW of here	earthquakes near San Miguel County
Montrose County, CO	59 km (37 mi)	WSW of here	earthquakes near Montrose County
Dolores County, CO	71 km (44 mi)	NNW of here	earthquakes near Dolores County
Mesa County, CO	92 km (57 mi)	SSW of here	earthquakes near Mesa County
Grand County, UT	96 km (60 mi)	SE of here	earthquakes near Grand County
Ouray County, CO	100 km (62 mi)	W of here	earthquakes near Ouray County

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

Aftershocks so far

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

1.5 26 km ESE of La Sal, Utah 09:47 UTC
2.0 29 km E of La Sal, Utah 17:02 UTC
1.6 28 km ESE of La Sal, Utah 00:29 UTC
2.1 28 km E of La Sal, Utah 20:41 UTC
2.2 28 km E of La Sal, Utah 00:37 UTC
2.0 28 km E of La Sal, Utah 22:13 UTC
2.1 28 km E of La Sal, Utah 13:15 UTC
1.6 30 km E of La Sal, Utah 02:45 UTC
1.5 29 km E of La Sal, Utah 04:42 UTC
1.5 29 km E of La Sal, Utah 07:30 UTC
2.1 20 km WSW of Naturita, Colorado 23:01 UTC
1.7 28 km E of La Sal, Utah 14:34 UTC
2.3 29 km E of La Sal, UT 03:02 UTC
1.9 28 km E of La Sal, Utah 21:01 UTC
1.7 28 km E of La Sal, Utah 02:54 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 07:36 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2019-03-04 — it released about 59 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

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.