Earthquake · reviewed by a seismologist
M 2.8ml
Earthquake near Monroe, UT
No earthquake was likely felt in Monroe in the 24 hours to 1:49 pm MST (20:49 UTC). The last one was M 3.3, 41 km (25 mi) SSW, at 10:44 pm MDT on 30 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Monroe
This page: a magnitude 2.8 earthquake was recorded 14 km (9 mi) west-southwest of Monroe, UT, at 10:01 pm MST on 20 December 2018 (05:01 UTC), 3.3 km deep. 4 people have reported feeling it to USGS.
USGS: 8 km SSW of Joseph, Utah
- When
- 10:01 pm MST on 20 December 2018 ()
- Where
- 14 km (9 mi) west-southwest of Monroe, UT · earthquakes near Monroe
- Magnitude
- M 2.8 (ml)
- Depth
- 3.3 km below the surface
- Felt
- 4 reports · strongest reported intensity II
- Measured shaking
- intensity IV (ShakeMap)
- Nearest
- Piute County, 28 km SSE
- Nearest mapped fault
- Annabella graben faults, 21 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 2820 days ago
Earthquake alerts for Monroe, UT
Get a notification in this browser when USGS records an earthquake near Monroe, UT. No account or email needed.
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 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 29 km (18 mi) from the epicentre. In Monroe, 14 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: Monroe 14 km, intensity III · Richfield 28 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 550 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.
- Mineral, Virginia 2011 M 5.8 28,000× the energy of this one
- Magna, Utah 2020 M 5.7 19,000× the energy of this one
- Around the size people start to feel M 3.0 1.7× the energy of this one
- This earthquake M 2.8 about 550 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 3 earthquakes of M5 or more within 50 km:
- 6.6 Near Marysvale, Utah · 14 km WSW of this epicentre
- 5.2 0 km SSW of Central Valley, Utah · 21 km NE of this epicentre
- 5.0 10 km NE of Marysvale, Utah · 12 km ESE 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 38.5645, -112.2645. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Piute County, UT | 28 km (17 mi) | SSE | earthquakes near Piute County |
| Sevier County, UT | 44 km (27 mi) | ENE | earthquakes near Sevier County |
| Millard County, UT | 87 km (54 mi) | WNW | earthquakes near Millard County |
| Beaver County, UT | 88 km (55 mi) | WSW | earthquakes near Beaver County |
| Sanpete County, UT | 108 km (67 mi) | NNE | earthquakes near Sanpete County |
| Garfield County, UT | 108 km (67 mi) | SE | earthquakes near Garfield 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.
- 1.8 6 km N of Joseph, Utah
- 1.5 23 km SSW of Kanosh, Utah
- 1.7 30 km W of Kanosh, Utah
- 1.9 29 km WSW of Kanosh, Utah
- 1.5 27 km WSW of Kanosh, Utah
- 1.8 30 km W of Kanosh, Utah
- 1.7 28 km W of Kanosh, Utah
- 2.1 28 km WSW of Kanosh, Utah
- 1.9 29 km W of Kanosh, Utah
- 1.9 26 km WSW of Kanosh, Utah
- 2.7 27 km WSW of Kanosh, Utah
- 1.6 29 km W of Kanosh, Utah
- 2.2 29 km WSW of Kanosh, Utah
- 3.1 29 km WSW of Kanosh, Utah
- 4.1 28 km W 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.