QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

Earthquake near Elk Plain, WA

No earthquake was likely felt in Elk Plain in the 24 hours to 6:07 pm PST (02:07 UTC). The last one was M 4.2, 46 km (28 mi) NNW, at 2:05 pm PDT on 29 September 2026, estimated intensity III (weak) in town; 9,329 felt reports to USGS. Every earthquake near Elk Plain

This page: a magnitude 2.8 earthquake was recorded 9 km (6 mi) south-southwest of Elk Plain, WA, at 10:52 pm PST on 7 January 2018 (06:52 UTC), 64 km deep. 21 people have reported feeling it to USGS.

USGS: 8 km SSW of Elk Plain, Washington

72 km (45 mi) S of Seattle, WA · 22 km (14 mi) SSE of Lakewood, WA

10:52 pm PST, Jan 7, 2018 · · 64 km deep · released about 400 lb of TNT

Every earthquake near Elk Plain Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Pierce County 22 kmThurston County 31 kmLewis County 44 kmMason County 70 kmKing County 73 kmKitsap County 76 kmCowlitz County 89 kmGrays Harbor County 107 kmWahkiakum 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
10:52 pm PST on 7 January 2018 ()
Where
9 km (6 mi) south-southwest of Elk Plain, WA · earthquakes near Elk Plain
Magnitude
M 2.8 (ml)
Depth
64 km below the surface
Felt
21 reports · strongest reported intensity III
Measured shaking
intensity II (ShakeMap)
Nearest
Pierce County, 22 km ENE
Nearest mapped fault
Olympia structure, 19 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3146 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 it was probably too small to be felt, even directly above it. In Elk Plain, 9 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: Graham, North Yelm, Yelm, Spanaway, Frederickson, Eatonville.

How big was it?

This earthquake released about 400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 38,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 27,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.4× the energy of this one
  4. This earthquake M 2.8 about 400 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 lists 5 earthquakes of M5 or more within 50 km:

  1. 6.8 The 2001 Nisqually, Washington Earthquake · 30 km NW of this epicentre
  2. 6.7 4 km WNW of Roy, Washington · 13 km WNW of this epicentre
  3. 6.7 1 km ENE of Dash Point, Washington · 39 km N of this epicentre
  4. 5.8 Puget Sound area, Washington · 49 km NW of this epicentre
  5. 5.0 3 km WSW of Des Moines, Washington · 46 km N of this epicentre

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 46.9755, -122.4283. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pierce County, WA 22 km (14 mi) ENE earthquakes near Pierce County
Thurston County, WA 31 km (19 mi) W earthquakes near Thurston County
Lewis County, WA 44 km (27 mi) S earthquakes near Lewis County
Mason County, WA 70 km (44 mi) NW earthquakes near Mason County
King County, WA 73 km (45 mi) NE earthquakes near King County
Kitsap County, WA 76 km (47 mi) NNW earthquakes near Kitsap 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. 1.5 3 km SW of Kapowsin, Washington
  2. 1.7 1 km SE of Kapowsin, Washington
  3. 1.6 6 km WNW of DuPont, Washington
  4. 2.1 6 km NNE of Olympia, Washington
  5. 1.6 6 km SW of La Grande, Washington
  6. 1.5 2 km ESE of Kapowsin, Washington
  7. 1.9 13 km NNE of Mossyrock, Washington
  8. 1.8 2 km E of Kapowsin, Washington
  9. 1.7 9 km SE of Enumclaw, Washington
  10. 1.9 1 km WNW of DuPont, Washington
  11. 1.7 8 km NNW of Olympia, Washington
  12. 1.6 3 km W of Federal Way, Washington
  13. 1.6 15 km NE of Ashford, Washington
  14. 1.8 1 km E of Browns Point, Washington
  15. 1.7 3 km E of Home, 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.