QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

14 km ENE of Halfway, Oregon

Yes. A magnitude 2.5 earthquake was recorded 14 km ENE of Halfway, Oregon, at 2:15 pm PST on 15 December 2017 (22:15 UTC), 3.6 km deep. 2 people have reported feeling it to USGS.

· 3.6 km deep · released about 170 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Adams County 39 kmWashington County 56 kmBaker County 64 kmWallowa County 75 kmUnion County 92 kmValley County 105 kmPayette County 106 kmGem County 107 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
Magnitude
M 2.5 (ml)
Depth
3.6 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Adams County, 39 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3173 days ago

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 22 km (14 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 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 44.9417, -116.9494. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Adams County, ID 39 km (24 mi) E earthquakes near Adams County
Washington County, ID 56 km (35 mi) SSE earthquakes near Washington County
Baker County, OR 64 km (40 mi) WSW earthquakes near Baker County
Wallowa County, OR 75 km (46 mi) NNW earthquakes near Wallowa County
Union County, OR 92 km (57 mi) WNW earthquakes near Union County
Valley County, ID 105 km (65 mi) E earthquakes near Valley County

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

Aftershocks so far

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

  1. 1.5 19 km ESE of Richland, Oregon
  2. 2.3 9 km E of Halfway, Oregon
  3. 2.1 17 km NNW of Halfway, Oregon
  4. 1.9 17 km NW of New Meadows, Idaho
  5. 2.1 19 km NNW of Halfway, Oregon
  6. 2.4 16 km E of Richland, Oregon
  7. 2.2 11 km ESE of Halfway, Oregon
  8. 1.5 20 km NW of New Meadows, Idaho
  9. 2.0 17 km NW of New Meadows, Idaho
  10. 2.4 21 km NW of New Meadows, Idaho
  11. 1.9 23 km ESE of Halfway, Oregon
  12. 2.7 21 km NW of Halfway, Oregon
  13. 2.3 19 km NW of New Meadows, Idaho
  14. 2.0 33 km NE of Halfway, Oregon
  15. 1.8 11 km ESE of Halfway, 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.