QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Manson, WA

USGS: 41 km WNW of Granite Falls, Washington

4:28 pm PDT, Jul 21, 2021 · · 7.3 km deep · released about 8.4 lb of TNT

Every earthquake near Manson Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Chelan County 22 kmSnohomish County 77 kmDouglas County 84 kmOkanogan County 92 kmSkagit County 95 kmKittitas County 102 kmKing County 103 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
4:28 pm PDT on 21 July 2021 ()
Where
46 km (28 mi) WNW of Manson, WA · earthquakes near Manson
Magnitude
M 1.6 (ml)
Depth
7.3 km below the surface
Felt
no reports yet
Nearest
Chelan County, 22 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1899 days ago

A magnitude 1.6 earthquake was recorded 46 km (28 mi) WNW of Manson, WA, at 4:28 pm PDT on 21 July 2021 (23:28 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 8.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,300,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.4 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 48.0452, -120.7240. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Chelan County, WA 22 km (14 mi) SSE earthquakes near Chelan County
Snohomish County, WA 77 km (48 mi) W earthquakes near Snohomish County
Douglas County, WA 84 km (52 mi) ESE earthquakes near Douglas County
Okanogan County, WA 92 km (57 mi) NE earthquakes near Okanogan County
Skagit County, WA 95 km (59 mi) WNW earthquakes near Skagit County
Kittitas County, WA 102 km (64 mi) S earthquakes near Kittitas County

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

Aftershocks so far

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

  1. 1.9 10 km SSW of Granite Falls, Washington
  2. 1.7 23 km NW of Granite Falls, Washington
  3. 1.6 15 km WSW of Methow, Washington
  4. 2.6 10 km WNW of Entiat, Washington
  5. 1.7 44 km WSW of Twisp, Washington
  6. 1.6 10 km NW of Entiat, Washington
  7. 1.8 44 km WSW of Twisp, Washington
  8. 1.6 8 km WNW of Entiat, Washington
  9. 1.7 9 km WNW of Entiat, Washington
  10. 1.9 9 km NW of Entiat, Washington
  11. 1.6 26 km NNW of Leavenworth, Washington
  12. 1.9 25 km NW of Leavenworth, Washington
  13. 2.2 24 km NW of Leavenworth, Washington
  14. 2.6 26 km NW of Leavenworth, Washington
  15. 1.8 13 km WNW of Granite Falls, 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.