Earthquake · reviewed by a seismologist
M 1.7ml
36 km NE of Spencer, Idaho
Yes. A magnitude 1.7 earthquake was recorded 36 km NE of Spencer, Idaho, at 4:16 am MDT on 27 October 2023 (10:16 UTC), 8.2 km deep.
- When
- Idaho today
- every earthquake in Idaho in the last 24 hours
- Magnitude
- M 1.7 (ml)
- Depth
- 8.2 km below the surface
- Felt
- no reports yet
- Nearest
- Clark County, 51 km SW
- Nearest mapped fault
- Centennial fault, under 1 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 1112 days ago
Earthquake alerts for West Yellowstone, MT
Get a notification in this browser when USGS records an earthquake near West Yellowstone, MT. 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 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 9 km (6 mi) from the epicentre. 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 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
- Magna, Utah 2020 M 5.7 970,000× the energy of this one
- Around the size people start to feel M 3.0 86× the energy of this one
- This earthquake M 1.7 about 11 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 4.3 on 2016-06-13 — about 8,800 times the energy of this one.
Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:
- 5.2 32 km WNW of Hebgen Lake Estates, Montana · 40 km NE of this epicentre
- 5.2 26 km WNW of Hebgen Lake Estates, Montana · 41 km NE of this epicentre
- 5.0 31 km W of Hebgen Lake Estates, Montana · 34 km NE of this epicentre
- 5.0 39 km W of Hebgen Lake Estates, Montana · 20 km ENE 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 44.6135, -111.9017. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Clark County, ID | 51 km (32 mi) | SW | earthquakes near Clark County |
| Fremont County, ID | 55 km (34 mi) | SE | earthquakes near Fremont County |
| Madison County, MT | 79 km (49 mi) | N | earthquakes near Madison County |
| Madison County, ID | 94 km (58 mi) | SSE | earthquakes near Madison County |
| Jefferson County, ID | 97 km (60 mi) | SSW | earthquakes near Jefferson County |
| Beaverhead County, MT | 97 km (60 mi) | NW | earthquakes near Beaverhead 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.
- 2.0 23 km N of Spencer, Idaho
- 1.8 23 km N of Spencer, Idaho
- 1.6 32 km W of Hebgen Lake Estates, Montana
- 1.7 26 km W of Hebgen Lake Estates, Montana
- 1.7 31 km NNE of Spencer, Idaho
- 1.8 26 km W of Hebgen Lake Estates, Montana
- 1.5 26 km W of Hebgen Lake Estates, Montana
- 2.3 26 km W of Hebgen Lake Estates, Montana
- 3.1 27 km W of Hebgen Lake Estates, Montana
- 1.5 27 km W of Hebgen Lake Estates, Montana
- 2.0 27 km W of Hebgen Lake Estates, Montana
- 2.0 37 km W of Hebgen Lake Estates, Montana
- 2.3 47 km NW of Island Park, Idaho
- 1.6 31 km SSE of Virginia City, Montana
- 1.8 40 km NNE of Spencer, 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.