QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Cheney, WA

USGS: 12 km N of Sprague, Washington

50 km (31 mi) SW of Spokane, WA

12:08 pm PDT, Aug 3, 2020 · · -0.5 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Lincoln County 38 kmSpokane County 50 kmAdams County 60 kmWhitman County 66 kmKootenai County 101 kmBenewah County 104 kmStevens County 109 kmGrant County 114 kmGarfield County 114 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
12:08 pm PDT on 3 August 2020 ()
Where
32 km (20 mi) WSW of Cheney, WA · earthquakes near Cheney
Magnitude
M 1.8 (ml)
Depth
-0.5 km below the surface
Felt
no reports yet
Nearest
Lincoln County, 38 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2252 days ago

A magnitude 1.8 earthquake was recorded 32 km (20 mi) WSW of Cheney, WA, at 12:08 pm PDT on 3 August 2020 (19:08 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Medical Lake, Davenport.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 47.4118, -117.9858. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lincoln County, WA 38 km (23 mi) WNW earthquakes near Lincoln County
Spokane County, WA 50 km (31 mi) ENE earthquakes near Spokane County
Adams County, WA 60 km (37 mi) SW earthquakes near Adams County
Whitman County, WA 66 km (41 mi) SSE earthquakes near Whitman County
Kootenai County, ID 101 km (63 mi) ENE earthquakes near Kootenai County
Benewah County, ID 104 km (65 mi) ESE earthquakes near Benewah County

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

Aftershocks so far

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

  1. 2.4 7 km ENE of Sprague, Washington
  2. 1.9 4 km ENE of Ritzville, Washington
  3. 2.4 9 km NE of Sprague, Washington
  4. 2.1 9 km NNW of Airway Heights, Washington
  5. 1.7 7 km NE of Sprague, Washington
  6. 1.5 8 km ENE of Four Lakes, Washington
  7. 2.5 9 km NE of Sprague, Washington
  8. 1.6 10 km NNW of Airway Heights, Washington
  9. 1.6 20 km NNW of Davenport, Washington
  10. 2.1 5 km ENE of Sprague, Washington
  11. 1.8 9 km NNW of Airway Heights, Washington
  12. 2.2 9 km NNW of Airway Heights, Washington
  13. 1.5 9 km NNW of Airway Heights, Washington
  14. 2.1 6 km NE of Sprague, Washington
  15. 2.3 8 km NE of Sprague, Washington

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.