Earthquake · reviewed by a seismologist
M 2.2ml
Earthquake near Salt Lake City, UT
USGS: 11 km SW of Henefer, Utah
34 km (21 mi) ENE of Salt Lake City, UT
- When
- 11:06 pm MST on 22 December 2018 ()
- Where
- 33 km (20 mi) NE of Salt Lake City, UT · earthquakes near Salt Lake City
- Magnitude
- M 2.2 (ml)
- Depth
- 7.6 km below the surface
- Felt
- 1 report · strongest reported intensity II
- Nearest
- Morgan County, 17 km N
- Nearest mapped fault
- Main Canyon fault, 6 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 2778 days ago
A magnitude 2.2 earthquake was recorded 33 km (20 mi) NE of Salt Lake City, UT, at 11:06 pm MST on 22 December 2018 (06:06 UTC). 1 person has reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
Earthquakes near other towns within 30 km: Morgan, Coalville, Summit Park, Silver Summit, Centerville, Bountiful.
How big was it?
This earthquake released about 58 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 260,000× the energy of this one
- Magna, Utah 2020 M 5.7 180,000× the energy of this one
- Around the size people start to feel M 3.0 16× the energy of this one
- This earthquake M 2.2 about 58 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 2 earthquakes of M5 or more within 50 km:
- 5.3 Near Salt Lake City, Utah · 32 km SW of this epicentre
- 5.0 1 km NE of Magna, Utah · 49 km WSW 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 40.9345, -111.5788. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Morgan County, UT | 17 km (11 mi) | N | earthquakes near Morgan County |
| Salt Lake County, UT | 42 km (26 mi) | SW | earthquakes near Salt Lake County |
| Weber County, UT | 45 km (28 mi) | NNW | earthquakes near Weber County |
| Summit County, UT | 52 km (32 mi) | E | earthquakes near Summit County |
| Davis County, UT | 54 km (33 mi) | WNW | earthquakes near Davis County |
| Wasatch County, UT | 75 km (47 mi) | SSE | earthquakes near Wasatch County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 2.1 6 km NNE of Magna, Utah
- 3.1 1 km NE of Magna, Utah
- 1.9 5 km NE of Magna, Utah
- 2.2 5 km NE of Magna, Utah
- 2.2 3 km NE of Magna, Utah
- 1.8 6 km NNE of Magna, Utah
- 2.3 6 km NNE of Magna, Utah
- 2.0 6 km NE of Magna, Utah
- 2.2 3 km NE of Magna, Utah
- 1.6 6 km NE of Magna, Utah
- 2.0 6 km NE of Magna, Utah
- 2.0 5 km NE of Magna, Utah
- 1.9 7 km NNE of Magna, Utah
- 1.9 7 km NE of Magna, Utah
- 2.3 7 km NNE of Magna, 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.