QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

Earthquake near Saint George, UT

No earthquake was likely felt in Saint George in the 24 hours to 8:34 am MST (15:34 UTC). The last one was M 4.0, 95 km (59 mi) W, at 1:16 am MDT on 6 June 2025, estimated intensity II (weak) in town; 37 felt reports to USGS. Every earthquake near Saint George

This page: a magnitude 2.8 earthquake was recorded 42 km (26 mi) northwest of Saint George, UT, at 8:37 pm MDT on 8 April 2018 (02:37 UTC), 6.9 km deep. 1 person has reported feeling it to USGS.

USGS: 24 km W of Veyo, Utah

45 km (28 mi) NW of St. George, UT

8:37 pm MDT, Apr 8, 2018 · · 6.9 km deep · released about 400 lb of TNT

Every earthquake near Saint George Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Washington County 44 kmLincoln County 86 kmIron County 88 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
8:37 pm MDT on 8 April 2018 ()
Where
42 km (26 mi) northwest of Saint George, UT · earthquakes near Saint George
Magnitude
M 2.8 (ml)
Depth
6.9 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Washington County, 44 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3052 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 25 km (16 mi) from the epicentre. In Saint George, 42 km away, the estimate is intensity II (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.

How big was it?

This earthquake released about 400 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 38,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 27,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.4× the energy of this one
  4. This earthquake M 2.8 about 400 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

The largest earthquake within 50 km since 2016 was M 4.2 on 2016-01-15 — about 170 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.3 Near Pine Valley, Utah · 43 km ENE of this epicentre
  2. 5.9 38 km ESE of Caliente, Nevada · 19 km NW of this epicentre
  3. 5.9 3 km SSE of Washington, Utah · 49 km ESE of this epicentre
  4. 5.3 36 km SE of Caliente, Nevada · 22 km WNW of this epicentre
  5. 5.2 36 km SE of Caliente, Nevada · 22 km WNW 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 37.3237, -113.9742. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Washington County, UT 44 km (27 mi) E earthquakes near Washington County
Lincoln County, NV 86 km (53 mi) WNW earthquakes near Lincoln County
Iron County, UT 88 km (55 mi) NE earthquakes near Iron County
Beaver County, UT 132 km (82 mi) NNE earthquakes near Beaver County

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

Aftershocks so far

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

  1. 2.1 9 km S of Saint George, Utah
  2. 1.6 4 km NE of Beaver Dam, Arizona
  3. 2.1 13 km SW of Enterprise, Utah
  4. 1.7 13 km SSW of Enterprise, Utah
  5. 1.6 14 km SW of Enterprise, Utah
  6. 2.2 14 km WSW of Enterprise, Utah
  7. 2.0 13 km SW of Enterprise, Utah
  8. 1.9 15 km SW of Enterprise, Utah
  9. 2.4 13 km SW of Enterprise, Utah
  10. 1.7 12 km WSW of Enterprise, Utah
  11. 2.6 13 km SW of Enterprise, Utah
  12. 1.9 13 km SW of Enterprise, Utah
  13. 1.6 41 km WSW of Veyo, Utah
  14. 1.7 14 km SW of Enterprise, Utah
  15. 3.8 14 km SW of Enterprise, 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.