QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

Earthquake near Tri-Cities, WA

No earthquake was likely felt in Tri-Cities in the 24 hours to 6:26 am PST (14:26 UTC). The last one was M 1.9, 12 km (7 mi) SSW, at 4:30 pm PDT on 3 September 2026, estimated intensity II (weak) in town. Every earthquake near Tri-Cities

This page: a magnitude 2.1 earthquake was recorded 31 km (20 mi) west of Tri-Cities, WA, at 4:12 am PDT on 28 July 2023 (11:12 UTC), 9.2 km deep.

USGS: Washington

25 km (16 mi) WSW of Richland, WA

4:12 am PDT, Jul 28, 2023 · · 9.2 km deep · released about 40 lb of TNT

10 km30 km60 km120 km N Benton County 7 kmFranklin County 65 kmMorrow County 86 kmWalla Walla County 86 kmYakima County 92 kmUmatilla County 95 kmKlickitat County 98 kmGilliam County 105 kmGrant County 113 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
4:12 am PDT on 28 July 2023 ()
Where
31 km (20 mi) west of Tri-Cities, WA · earthquakes near Tri-Cities
Magnitude
M 2.1 (ml)
Depth
9.2 km below the surface
Felt
no reports yet
Nearest
Benton County, 7 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1198 days ago

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 14 km (9 mi) from the epicentre. In Tri-Cities, 31 km away, the estimate is intensity II (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.

Earthquakes near other towns within 30 km: Benton City, Prosser, West Richland, Grandview, Richland.

How big was it?

This earthquake released about 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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 46.2012, -119.6000. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Benton County, WA 7 km (4 mi) ENE earthquakes near Benton County
Franklin County, WA 65 km (41 mi) NE earthquakes near Franklin County
Morrow County, OR 86 km (54 mi) S earthquakes near Morrow County
Walla Walla County, WA 86 km (54 mi) E earthquakes near Walla Walla County
Yakima County, WA 92 km (57 mi) WNW earthquakes near Yakima County
Umatilla County, OR 95 km (59 mi) SE earthquakes near Umatilla County

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

Aftershocks so far

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

  1. 1.7 1 km WNW of Highland, Washington
  2. 1.6 11 km SE of Desert Aire, Washington
  3. 2.3 11 km SE of Desert Aire, Washington
  4. 1.9 11 km SE of Desert Aire, Washington
  5. 1.6 11 km SE of Desert Aire, Washington
  6. 1.6 11 km SE of Desert Aire, Washington
  7. 2.4 11 km SE of Desert Aire, Washington
  8. 1.8 4 km SSE of Kennewick, Washington
  9. 2.3 4 km SSW of West Richland, Washington
  10. 1.7 10 km SSW of Tri-Cities, Washington
  11. 2.0 4 km SE of Umatilla, Oregon
  12. 1.6 10 km ENE of Prosser, Washington
  13. 1.9 12 km SE of Desert Aire, Washington
  14. 1.6 12 km SE of Desert Aire, Washington
  15. 1.8 12 km SE of Desert Aire, 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.