QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

Earthquake near Williams, CA

No earthquake was likely felt in Williams in the 24 hours to 1:21 am PST (09:21 UTC). The last one was M 4.0, 79 km (49 mi) WNW, at 5:01 am PDT on 28 October 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Williams

This page: a magnitude 3.2 earthquake was recorded 7 km (4 mi) west-southwest of Williams, CA, at 3:19 pm PDT on 30 June 2021 (22:19 UTC), less than 1 km deep. 25 people have reported feeling it to USGS.

USGS: 7km WSW of Williams, CA

91 km (56 mi) NW of Sacramento, CA · 50 km (31 mi) W of Yuba City, CA

3:19 pm PDT, Jun 30, 2021 · · -0.3 km deep · released about 1,700 lb of TNT

10 km30 km60 km120 km N Colusa County 5 kmLake County 45 kmSutter County 46 kmGlenn County 54 kmYolo County 58 kmNapa County 70 kmYuba County 77 kmButte County 79 kmSonoma County 91 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
3:19 pm PDT on 30 June 2021 ()
Where
7 km (4 mi) west-southwest of Williams, CA · earthquakes near Williams
Magnitude
M 3.2 (ml)
Depth
-0.3 km below the surface
Felt
25 reports · strongest reported intensity V
Measured shaking
intensity IV (ShakeMap)
Nearest
Colusa County, 5 km NNW
Nearest mapped fault
Great Valley thrust fault system, 5 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 1859 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, people at rest would likely notice it out to about 45 km (28 mi) from the epicentre. In Williams, 7 km away, the estimate is intensity III (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: Clearlake 40 km, intensity II · Willows 43 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,700 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 200,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 8,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,200× the energy of this one
  4. This earthquake M 3.2 about 1,700 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.8× more

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 39.1353, -122.2215. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Colusa County, CA 5 km (3 mi) NNW earthquakes near Colusa County
Lake County, CA 45 km (28 mi) W earthquakes near Lake County
Sutter County, CA 46 km (29 mi) ESE earthquakes near Sutter County
Glenn County, CA 54 km (34 mi) NNW earthquakes near Glenn County
Yolo County, CA 58 km (36 mi) SSE earthquakes near Yolo County
Napa County, CA 70 km (44 mi) S earthquakes near Napa County

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

Aftershocks so far

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

  1. 2.5 14km W of Williams, CA
  2. 1.8 19km NE of Upper Lake, CA
  3. 2.6 15km E of Willows, CA
  4. 1.6 12km ESE of Hidden Valley Lake, CA
  5. 2.2 12km ESE of Hidden Valley Lake, CA
  6. 1.8 10km E of Clearlake, CA
  7. 2.6 16km E of Willows, CA
  8. 1.6 10km ENE of Hidden Valley Lake, CA
  9. 2.3 16km E of Willows, CA
  10. 2.5 8km NW of Dunnigan, CA
  11. 1.8 6km ESE of Clearlake Oaks, CA
  12. 1.7 17km NNE of Nice, CA
  13. 2.1 7km E of Clearlake Oaks, CA
  14. 1.5 8km WSW of Williams, CA

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.