QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Westwood, CA

No earthquake was likely felt in Westwood in the 24 hours to 12:14 pm PST (20:14 UTC). The last one was M 2.1, 12 km (7 mi) SSW, at 8:09 am PDT on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Westwood

This page: a magnitude 2.1 earthquake was recorded 14 km (9 mi) south-southwest of Westwood, CA, at 5:49 am PDT on 22 July 2022 (12:49 UTC), 6.5 km deep.

USGS: 3km N of Canyondam, CA

5:49 am PDT, Jul 22, 2022 · · 6.5 km deep · released about 41 lb of TNT

10 km30 km60 km120 km N Plumas County 31 kmLassen County 70 kmButte County 74 kmSierra County 83 kmTehama County 98 kmNevada County 103 kmShasta County 103 kmYuba County 105 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
5:49 am PDT on 22 July 2022 ()
Where
14 km (9 mi) south-southwest of Westwood, CA · earthquakes near Westwood
Magnitude
M 2.1 (md)
Depth
6.5 km below the surface
Felt
no reports yet
Nearest
Plumas County, 31 km SE
Nearest mapped fault
Almanor fault, under 1 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 1574 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 16 km (10 mi) from the epicentre. In Westwood, 14 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.

Likely felt in: Greenville 12 km, intensity II · Westwood 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 41 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 5.8 370,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 260,000× the energy of this one
  3. Around the size people start to feel M 3.0 23× the energy of this one
  4. This earthquake M 2.1 about 41 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 2 earthquakes of M5 or more within 50 km:

  1. 5.7 2 km NNE of Canyondam, California · 2 km E of this epicentre
  2. 5.5 15 km NE of Mineral, California · 44 km NW 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 40.1932, -121.0793. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Plumas County, CA 31 km (19 mi) SE earthquakes near Plumas County
Lassen County, CA 70 km (43 mi) NNE earthquakes near Lassen County
Butte County, CA 74 km (46 mi) SW earthquakes near Butte County
Sierra County, CA 83 km (52 mi) SE earthquakes near Sierra County
Tehama County, CA 98 km (61 mi) W earthquakes near Tehama County
Nevada County, CA 103 km (64 mi) SSE earthquakes near Nevada County

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

Aftershocks so far

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

  1. 1.8 14km NE of Mineral, CA
  2. 1.9 4km W of Mineral, CA
  3. 1.5 4 km W of Greenville, California
  4. 1.7 7 km S of Canyondam, California
  5. 1.6 Northern California
  6. 1.7 13 km NNW of Belden, California
  7. 1.9 17km S of Mineral, CA
  8. 1.6 1 km NNE of Paxton, California
  9. 1.9 14km WSW of Chester, CA
  10. 1.5 2 km WSW of Canyondam, California
  11. 1.5 1 km WNW of Keddie, California
  12. 1.7 1 km W of Keddie, California
  13. 1.6 0 km E of Paxton, California
  14. 2.8 3km N of Greenhorn, CA
  15. 1.8 2 km SSE of Canyondam, California

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.