Earthquake · reviewed by a seismologist
M 1.8ml
Earthquake near Richfield, UT
No earthquake was likely felt in Richfield in the 24 hours to 4:19 am MST (11:19 UTC). The last one was M 3.2, 34 km (21 mi) W, at 8:35 am MDT on 22 April 2026, estimated intensity II (weak) in town; 6 felt reports to USGS. Every earthquake near Richfield
This page: a magnitude 1.8 earthquake was recorded 50 km (31 mi) south-southwest of Richfield, UT, at 10:08 am MDT on 7 August 2023 (16:08 UTC), 4.7 km deep.
USGS: 11 km S of Marysvale, Utah
- When
- 10:08 am MDT on 7 August 2023 ()
- Where
- 50 km (31 mi) south-southwest of Richfield, UT · earthquakes near Richfield
- Magnitude
- M 1.8 (ml)
- Depth
- 4.7 km below the surface
- Felt
- no reports yet
- Nearest
- Piute County, 11 km E
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1194 days ago
Earthquake alerts for Richfield, UT
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Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 Richfield, 50 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 13 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.
- Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
- Magna, Utah 2020 M 5.7 810,000× the energy of this one
- Around the size people start to feel M 3.0 72× the energy of this one
- This earthquake M 1.8 about 13 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 4.4 on 2020-10-03 — about 9,800 times the energy of this one.
Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:
- 6.6 Near Marysvale, Utah · 21 km NW of this epicentre
- 5.2 0 km SSW of Central Valley, Utah · 41 km NNE of this epicentre
- 5.0 10 km NE of Marysvale, Utah · 21 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 38.3467, -112.2508. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Piute County, UT | 11 km (7 mi) | E | earthquakes near Piute County |
| Sevier County, UT | 59 km (36 mi) | NE | earthquakes near Sevier County |
| Beaver County, UT | 86 km (54 mi) | W | earthquakes near Beaver County |
| Garfield County, UT | 90 km (56 mi) | SE | earthquakes near Garfield County |
| Millard County, UT | 102 km (64 mi) | NW | earthquakes near Millard County |
| Iron County, UT | 104 km (65 mi) | WSW | earthquakes near Iron County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
57 earthquakes have been recorded within 50 km since this one.
- 1.7 6 km SSE of Joseph, Utah
- 2.4 12 km SSW of Beaver, Utah
- 1.6 9 km SSW of Monroe, Utah
- 1.6 19 km SSW of Antimony, Utah
- 2.2 19 km ENE of Antimony, Utah
- 2.2 14 km SE of Beaver, Utah
- 2.5 20 km SSW of Antimony, Utah
- 1.8 18 km SSW of Antimony, Utah
- 1.8 19 km NNE of Paragonah, Utah
- 1.6 21 km SSE of Beaver, Utah
- 1.8 22 km SSW of Kanosh, Utah
- 1.8 0 km W of Circleville, Utah
- 1.7 13 km S of Beaver, Utah
- 1.7 2 km WSW of Marysvale, Utah
- 1.7 22 km SSW of Kanosh, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.