QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Fredonia, AZ

No earthquake was likely felt in Fredonia in the 24 hours to 5:45 pm MST (00:45 UTC). The last one was M 2.3, 8 km (5 mi) SE, at 5:18 pm MST on 6 November 2025, estimated intensity II (weak) in town. Every earthquake near Fredonia

This page: a magnitude 1.8 earthquake was recorded 8 km (5 mi) east of Fredonia, AZ, at 9:35 pm MST on 22 September 2023 (04:35 UTC), 21 km deep.

USGS: 8 km E of Fredonia, Arizona

9:35 pm MST, Sep 22, 2023 · · 21 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Kane County 66 kmWashington County 100 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
9:35 pm MST on 22 September 2023 ()
Where
8 km (5 mi) east of Fredonia, AZ · earthquakes near Fredonia
Magnitude
M 1.8 (ml)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Kane County, 66 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1143 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Fredonia, 8 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.

Earthquakes near other towns within 30 km: Kanab.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× the energy of this one
  4. This earthquake M 1.8 about 16 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. 5.6 21 km SE of Fredonia, Arizona · 17 km SSE 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 36.9467, -112.4355. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kane County, UT 66 km (41 mi) NE earthquakes near Kane County
Washington County, UT 100 km (62 mi) WNW earthquakes near Washington County
Garfield County, UT 131 km (82 mi) NE earthquakes near Garfield County
Iron County, UT 132 km (82 mi) NW earthquakes near Iron County

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

Aftershocks so far

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

  1. 1.7 16 km ESE of Kanab, Utah
  2. 1.6 12 km NE of Hildale, Utah
  3. 2.0 8 km SE of Fredonia, Arizona
  4. 1.7 9 km E of Springdale, Utah
  5. 2.0 9 km E of Springdale, Utah
  6. 2.5 9 km E of Springdale, Utah
  7. 1.7 4 km WNW of Fredonia, Arizona
  8. 1.7 5 km W of Fredonia, Arizona
  9. 1.9 9 km E of Springdale, Utah
  10. 1.8 17 km E of Kanab, Utah
  11. 1.5 13 km ENE of Hildale, Utah
  12. 1.7 10 km E of Springdale, Utah
  13. 1.7 12 km SSW of Orderville, Utah
  14. 1.7 9 km E of Springdale, Utah
  15. 1.6 18 km S of Cane Beds, Arizona

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.