QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Chester, CA

No earthquake was likely felt in Chester in the 24 hours to 11:41 pm PST (07:41 UTC). The last one was M 2.1, 17 km (11 mi) SE, at 8:09 am PDT on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Chester

This page: a magnitude 1.6 earthquake was recorded 31 km (19 mi) northwest of Chester, CA, at 5:55 am PDT on 12 May 2022 (12:55 UTC), less than 1 km deep.

USGS: 15km E of Viola, CA

86 km (53 mi) NNE of Chico, CA

5:55 am PDT, May 12, 2022 · · 0.1 km deep · released about 6.8 lb of TNT

10 km30 km60 km120 km N Shasta County 54 kmTehama County 74 kmLassen County 79 kmPlumas County 80 kmButte County 93 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
5:55 am PDT on 12 May 2022 ()
Where
31 km (19 mi) northwest of Chester, CA · earthquakes near Chester
Magnitude
M 1.6 (md)
Depth
0.1 km below the surface
Felt
no reports yet
Nearest
Shasta County, 54 km WNW
Nearest mapped fault
Hat Creek fault, 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 1645 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 11 km (7 mi) from the epicentre. In Chester, 31 km away, the estimate is intensity I (not felt). 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.

How big was it?

This earthquake released about 6.8 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 2,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.8 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 one earthquake of M5 or more within 50 km:

  1. 5.5 15 km NE of Mineral, California · 6 km SE 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 40.4950, -121.5067. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Shasta County, CA 54 km (34 mi) WNW earthquakes near Shasta County
Tehama County, CA 74 km (46 mi) WSW earthquakes near Tehama County
Lassen County, CA 79 km (49 mi) ENE earthquakes near Lassen County
Plumas County, CA 80 km (50 mi) SE earthquakes near Plumas County
Butte County, CA 93 km (58 mi) S earthquakes near Butte County
Glenn County, CA 125 km (78 mi) SW earthquakes near Glenn County

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

Aftershocks so far

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

  1. 2.0 13km ESE of Millville, CA
  2. 1.9 10km SSW of Manton, CA
  3. 1.8 10km W of Manton, CA
  4. 1.8 8km NW of Chester, CA
  5. 2.3 15km NW of Chester, CA
  6. 1.9 16km NW of Chester, CA
  7. 2.2 17km NW of Chester, CA
  8. 1.9 17km NW of Chester, CA
  9. 1.8 16km NW of Chester, CA
  10. 1.9 16km NW of Chester, CA
  11. 1.8 18km NW of Chester, CA
  12. 1.9 16km NW of Chester, CA
  13. 2.0 17km NW of Chester, CA
  14. 1.7 18km NW of Chester, CA
  15. 1.9 16km NW of Chester, 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.