Earthquake · reviewed by a seismologist
M 3.1ml
Earthquake near Hoback, WY
No earthquake was likely felt in Hoback in the 24 hours to 4:56 pm MST (23:56 UTC). The last one was M 2.7, 5 km (3 mi) E, at 6:18 pm MST on 6 November 2026, estimated intensity III (weak) in town; 1 felt report to USGS. Every earthquake near Hoback
This page: a magnitude 3.1 earthquake was recorded 12 km (7 mi) west-northwest of Hoback, WY, at 6:17 am MDT on 22 August 2018 (12:17 UTC), 1.1 km deep. 25 people have reported feeling it to USGS.
USGS: 11 km WNW of Hoback, Wyoming
- When
- 6:17 am MDT on 22 August 2018 ()
- Where
- 12 km (7 mi) west-northwest of Hoback, WY · earthquakes near Hoback
- Magnitude
- M 3.1 (ml)
- Depth
- 1.1 km below the surface
- Felt
- 25 reports · strongest reported intensity III
- Nearest
- Teton County, 53 km NNW
- Nearest mapped fault
- Grand Valley fault, 13 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 2932 days ago
Earthquake alerts for Hoback, WY
Get a notification in this browser when USGS records an earthquake near Hoback, WY. 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 42 km (26 mi) from the epicentre. In Hoback, 12 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: Hoback 12 km, intensity III · Jackson 21 km, intensity II · Star Valley Ranch 40 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 250,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
- Magna, Utah 2020 M 5.7 7,900× the energy of this one
- This earthquake M 3.1 about 1,300 lb of TNT
- Around the size people start to feel M 3.0 this one released 1.4× more
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 4.0 on 2016-02-26 — about 22 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.3 Southeastern Idaho · 48 km SW 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 43.3309, -110.9146. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Teton County, ID | 53 km (33 mi) | NNW | earthquakes near Teton County |
| Bonneville County, ID | 58 km (36 mi) | W | earthquakes near Bonneville County |
| Madison County, ID | 79 km (49 mi) | NW | earthquakes near Madison County |
| Caribou County, ID | 79 km (49 mi) | SW | earthquakes near Caribou County |
| Teton County, WY | 89 km (55 mi) | NNE | earthquakes near Teton County |
| Sublette County, WY | 102 km (64 mi) | SE | earthquakes near Sublette County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
56 earthquakes have been recorded within 50 km since this one.
- 1.5 14 km E of Kelly, Wyoming
- 1.7 11 km ESE of Alpine, Wyoming
- 2.0 19 km N of Alpine Northeast, Wyoming
- 1.9 14 km SW of Wilson, Wyoming
- 1.6 12 km SW of Wilson, Wyoming
- 1.5 6 km ESE of Victor, Idaho
- 2.0 southern Idaho
- 2.0 11 km NE of Hoback, Wyoming
- 1.5 1 km SW of Driggs, Idaho
- 1.9 6 km WSW of Rafter J Ranch, Wyoming
- 2.1 9 km W of Hoback, Wyoming
- 1.8 2 km S of Alta, Wyoming
- 1.9 southern Idaho
- 1.6 1 km S of Driggs, Idaho
- 1.5 2 km S of Driggs, Idaho
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.