QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9ml

8 km NNE of Magna, Utah

· 10.0 km deep · released about 12 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Salt Lake County 16 kmDavis County 31 kmMorgan County 53 kmWeber County 57 kmUtah County 80 kmWasatch County 90 kmSummit County 92 kmTooele County 97 kmCache County 109 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 3.9 (ml)
Depth
10.0 km below the surface
Felt
4434 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Salt Lake County, 16 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2016 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 4434 people have reported feeling it to USGS.

How big was it?

This earthquake released about 12 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 14,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 620× the energy of this one
  3. Magna, Utah 2020 M 5.7 440× the energy of this one
  4. This earthquake M 3.9 about 12 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 26× 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

Epicentre 40.7790, -112.0530. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Salt Lake County, UT 16 km (10 mi) NW of here earthquakes near Salt Lake County
Davis County, UT 31 km (19 mi) SSE of here earthquakes near Davis County
Morgan County, UT 53 km (33 mi) SW of here earthquakes near Morgan County
Weber County, UT 57 km (35 mi) SSW of here earthquakes near Weber County
Utah County, UT 80 km (50 mi) NNW of here earthquakes near Utah County
Wasatch County, UT 90 km (56 mi) WNW of here earthquakes near Wasatch County

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

Aftershocks so far

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

  1. 1.6 5 km NNE of West Valley City, Utah
  2. 1.7 7 km W of Salt Lake City, Utah
  3. 1.9 7 km W of Salt Lake City, Utah
  4. 2.0 Utah
  5. 1.6 6 km NNE of Magna, Utah
  6. 2.3 4 km NE of Magna, Utah
  7. 2.2 7 km W of North Salt Lake, UT
  8. 1.6 2 km ENE of Magna, Utah
  9. 2.5 Utah
  10. 1.9 6 km NE of Magna, Utah
  11. 1.9 6 km NNW of West Valley City, Utah
  12. 2.1 6 km NE of Magna, Utah
  13. 2.6 6 km NE of Magna, Utah
  14. 1.6 5 km NE of West Valley City, Utah
  15. 2.4 13 km NNW of Magna, Utah

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.

For this area

The largest earthquake within 50 km in our catalogue was M 5.7 on 2020-03-18 — it released about 440 times the energy of this one.

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

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.