QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4ml

Earthquake near Magna, UT

No earthquake was likely felt in Magna in the 24 hours to 12:57 am MST (07:57 UTC). The last one was M 2.2, 6 km (3 mi) ENE, at 8:46 am MDT on 17 June 2026, estimated intensity II (weak) in town; 28 felt reports to USGS. Every earthquake near Magna

This page: a magnitude 3.4 earthquake was recorded 2 km (2 mi) northeast of Magna, UT, at 8:06 am MDT on 18 March 2020 (14:06 UTC), 11 km deep. 76 people have reported feeling it to USGS.

USGS: 2 km NE of Magna, Utah

7 km (5 mi) NW of West Valley City, UT

8:06 am MDT, Mar 18, 2020 · · 11 km deep · released about 2 tons of TNT

10 km30 km60 km120 km N Salt Lake County 15 kmDavis County 36 kmMorgan County 59 kmWeber County 63 kmUtah County 76 kmWasatch County 89 kmTooele County 92 kmSummit County 95 kmCache County 116 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
8:06 am MDT on 18 March 2020 ()
Where
2 km (2 mi) northeast of Magna, UT · earthquakes near Magna
Magnitude
M 3.4 (ml)
Depth
11 km below the surface
Felt
76 reports · strongest reported intensity VI
Measured shaking
intensity IV (ShakeMap)
Nearest
Salt Lake County, 15 km ESE
Nearest mapped fault
West Valley fault, 7 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2351 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 57 km (35 mi) from the epicentre. In Magna, 2 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.

Likely felt in: Magna 2 km, intensity III · West Valley City 8 km, intensity III · Kearns 10 km, intensity III · Taylorsville 14 km, intensity III · Salt Lake City 17 km, intensity III · Murray 18 km, intensity III · West Jordan 18 km, intensity III · Millcreek 18 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 2 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 86,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,700× the energy of this one
  4. This earthquake M 3.4 about 2 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.1× 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.

For this area

The largest earthquake within 50 km since 2016 was M 5.7 on 2020-03-18 — about 2,700 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.3 Near Salt Lake City, Utah · 24 km E of this epicentre
  2. 5.0 1 km NE of Magna, Utah · 1 km SSW of this epicentre

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 40.7267, -112.0845. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Salt Lake County, UT 15 km (9 mi) ESE earthquakes near Salt Lake County
Davis County, UT 36 km (22 mi) NNW earthquakes near Davis County
Morgan County, UT 59 km (37 mi) NE earthquakes near Morgan County
Weber County, UT 63 km (39 mi) NNE earthquakes near Weber County
Utah County, UT 76 km (47 mi) SSE earthquakes near Utah County
Wasatch County, UT 89 km (56 mi) ESE 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. 2.0 6 km NE of Magna, Utah
  2. 2.5 7 km NNW of West Valley City, Utah
  3. 1.6 6 km NNE of Magna, Utah
  4. 1.6 3 km NE of Magna, Utah
  5. 1.9 6 km NE of Magna, Utah
  6. 2.0 6 km NNE of Magna, Utah
  7. 2.6 7 km NE of Magna, Utah
  8. 2.6 6 km NE of Magna, Utah
  9. 1.6 6 km NNE of Magna, Utah
  10. 1.6 6 km NE of Magna, Utah
  11. 1.6 Utah
  12. 1.5 6 km NE of Magna, Utah
  13. 2.6 6 km NE of Magna, Utah
  14. 1.6 7 km NNE of Magna, Utah
  15. 1.7 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.

On USGS

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