QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

Earthquake near Richland, WA

USGS: 13 km N of Richland, Washington

14 km (9 mi) NNE of Richland, WA

9:27 pm PDT, Sep 28, 2018 · · 0.1 km deep · released about 24 lb of TNT

10 km30 km60 km120 km N Benton County 28 kmFranklin County 31 kmWalla Walla County 62 kmAdams County 88 kmGrant County 91 kmUmatilla County 100 kmColumbia County 104 kmMorrow County 113 kmYakima 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
9:27 pm PDT on 28 September 2018 ()
Where
14 km (9 mi) N of Richland, WA · earthquakes near Richland
Magnitude
M 1.9 (ml)
Depth
0.1 km below the surface
Felt
5 reports · strongest reported intensity IV
Nearest
Benton County, 28 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2862 days ago

A magnitude 1.9 earthquake was recorded 14 km (9 mi) N of Richland, WA, at 9:27 pm PDT on 28 September 2018 (04:27 UTC). 5 people have reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: West Richland, Tri-Cities, West Pasco, Basin City, Pasco, Kennewick.

How big was it?

This earthquake released about 24 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 640,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 450,000× the energy of this one
  3. Around the size people start to feel M 3.0 40× the energy of this one
  4. This earthquake M 1.9 about 24 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 46.4090, -119.2573. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Benton County, WA 28 km (18 mi) SW earthquakes near Benton County
Franklin County, WA 31 km (19 mi) ENE earthquakes near Franklin County
Walla Walla County, WA 62 km (39 mi) ESE earthquakes near Walla Walla County
Adams County, WA 88 km (55 mi) NE earthquakes near Adams County
Grant County, WA 91 km (56 mi) N earthquakes near Grant County
Umatilla County, OR 100 km (62 mi) SSE earthquakes near Umatilla County

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

Aftershocks so far

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

  1. 2.0 6 km WNW of Highland, Washington
  2. 1.9 10 km ENE of Prosser, Washington
  3. 1.8 10 km N of Irrigon, Oregon
  4. 2.2 4 km SSW of West Richland, Washington
  5. 1.6 1 km SE of Benton City, Washington
  6. 1.6 Washington
  7. 1.9 12 km W of Highland, Washington
  8. 2.0 6 km W of Highland, Washington
  9. 1.5 16 km N of Umatilla, Oregon
  10. 1.6 3 km NNW of Highland, Washington
  11. 1.9 3 km WSW of Benton City, Washington
  12. 1.6 4 km WSW of Benton City, Washington
  13. 1.6 19 km S of Benton City, Washington
  14. 1.9 10 km ENE of Prosser, Washington
  15. 1.9 5 km SSW of West Richland, 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.