QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

Earthquake near Enterprise, OR

USGS: 20 km N of Halfway, Oregon

11:33 am PDT, Aug 21, 2017 · · 4.5 km deep · released about 58 lb of TNT

Every earthquake near Enterprise Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Adams County 57 kmWallowa County 59 kmBaker County 60 kmUnion County 73 kmWashington County 74 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:33 am PDT on 21 August 2017 ()
Where
41 km (26 mi) SSE of Enterprise, OR · earthquakes near Enterprise
Magnitude
M 2.2 (ml)
Depth
4.5 km below the surface
Felt
no reports yet
Nearest
Adams County, 57 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3329 days ago

A magnitude 2.2 earthquake was recorded 41 km (26 mi) SSE of Enterprise, OR, at 11:33 am PDT on 21 August 2017 (18:33 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

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.

  1. Mineral, Virginia 2011 M 5.8 260,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 180,000× the energy of this one
  3. Around the size people start to feel M 3.0 16× the energy of this one
  4. 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 since 1900 lists no earthquake of M5 or more within 50 km.

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 45.0680, -117.1320. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Adams County, ID 57 km (35 mi) ESE earthquakes near Adams County
Wallowa County, OR 59 km (36 mi) N earthquakes near Wallowa County
Baker County, OR 60 km (37 mi) SW earthquakes near Baker County
Union County, OR 73 km (45 mi) WNW earthquakes near Union County
Washington County, ID 74 km (46 mi) SSE earthquakes near Washington County
Valley County, ID 121 km (75 mi) E earthquakes near Valley County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

25 earthquakes have been recorded within 50 km since this one.

  1. 2.3 9 km E of Halfway, Oregon
  2. 2.1 17 km NNW of Halfway, Oregon
  3. 2.1 19 km NE of Baker City, Oregon
  4. 2.1 19 km NNW of Halfway, Oregon
  5. 2.4 16 km E of Richland, Oregon
  6. 2.6 24 km ENE of Baker City, Oregon
  7. 2.2 11 km ESE of Halfway, Oregon
  8. 1.9 23 km ESE of Halfway, Oregon
  9. 2.7 21 km NW of Halfway, Oregon
  10. 1.6 21 km ESE of Cove, Oregon
  11. 2.0 33 km NE of Halfway, Oregon
  12. 1.8 11 km ESE of Halfway, Oregon
  13. 2.3 15 km SE of Halfway, Oregon
  14. 3.0 8 km WSW of Richland, Oregon
  15. 2.2 12 km W of Richland, Oregon

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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.