QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Ephraim, UT

No earthquake was likely felt in Ephraim in the 24 hours to 1:42 pm MST (20:42 UTC). The last one was M 1.9, 10 km (7 mi) S, at 2:29 am MDT on 22 June 2026, estimated intensity II (weak) in town. Every earthquake near Ephraim

This page: a magnitude 1.7 earthquake was recorded 33 km (20 mi) west-northwest of Ephraim, UT, at 10:08 pm MDT on 2 September 2021 (04:08 UTC), less than 1 km deep.

USGS: 17 km SSW of Levan, Utah

95 km (59 mi) SSW of Provo, UT

10:08 pm MDT, Sep 2, 2021 · · 0.6 km deep · released about 9.6 lb of TNT

10 km30 km60 km120 km N Sanpete County 33 kmSevier County 76 kmJuab County 78 kmUtah County 81 kmMillard County 114 kmEmery 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
10:08 pm MDT on 2 September 2021 ()
Where
33 km (20 mi) west-northwest of Ephraim, UT · earthquakes near Ephraim
Magnitude
M 1.7 (ml)
Depth
0.6 km below the surface
Felt
no reports yet
Nearest
Sanpete County, 33 km E
Nearest mapped fault
Wasatch fault, 4 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 1896 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Ephraim, 33 km away, the estimate is intensity I (not felt). 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 9.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 99× the energy of this one
  4. This earthquake M 1.7 about 9.6 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.0 3 km WSW of Nephi, Utah · 31 km NNE 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 39.4240, -111.9563. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sanpete County, UT 33 km (21 mi) E earthquakes near Sanpete County
Sevier County, UT 76 km (47 mi) S earthquakes near Sevier County
Juab County, UT 78 km (49 mi) WNW earthquakes near Juab County
Utah County, UT 81 km (50 mi) NNE earthquakes near Utah County
Millard County, UT 114 km (71 mi) WSW earthquakes near Millard County
Emery County, UT 116 km (72 mi) ESE earthquakes near Emery County

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

Aftershocks so far

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

  1. 1.6 11 km ESE of Holden, Utah
  2. 1.6 5 km WNW of Scipio, Utah
  3. 1.7 16 km N of Fayette, Utah
  4. 1.6 16 km N of Fayette, Utah
  5. 1.9 16 km N of Fayette, Utah
  6. 1.7 15 km N of Fayette, Utah
  7. 1.7 9 km NNW of Fayette, Utah
  8. 1.6 4 km WNW of Centerfield, Utah
  9. 1.7 7 km NNE of Moroni, Utah
  10. 2.1 8 km NNW of Fayette, Utah
  11. 1.7 8 km ENE of Ephraim, Utah
  12. 2.9 6 km W of Gunnison, Utah
  13. 1.9 6 km SSE of Centerfield, Utah
  14. 1.6 6 km SSE of Centerfield, Utah
  15. 1.9 11 km ESE of Scipio, 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.