QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Quincy, CA

No earthquake was likely felt in Quincy in the 24 hours to 8:09 am PST (16:09 UTC). The last one was M 2.3, 7 km (4 mi) NE, at 5:11 am PST on 7 November 2026, estimated intensity II (weak) in town. Every earthquake near Quincy

This page: a magnitude 2.2 earthquake was recorded 6 km (4 mi) south-southeast of Quincy, CA, at 3:24 pm PDT on 30 June 2021 (22:24 UTC), 9.3 km deep.

USGS: 6km SSE of Quincy, CA

100 km (62 mi) WNW of Reno, NV

3:24 pm PDT, Jun 30, 2021 · · 9.3 km deep · released about 58 lb of TNT

10 km30 km60 km120 km N Plumas County 15 kmSierra County 49 kmButte County 63 kmNevada County 67 kmYuba County 77 kmPlacer County 93 kmLassen County 96 kmTehama County 114 kmSutter County 115 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
3:24 pm PDT on 30 June 2021 ()
Where
6 km (4 mi) south-southeast of Quincy, CA · earthquakes near Quincy
Magnitude
M 2.2 (md)
Depth
9.3 km below the surface
Felt
no reports yet
Nearest
Plumas County, 15 km NE
Nearest mapped fault
Mohawk Valley fault, 17 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 1960 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 Quincy, 6 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: East Quincy 6 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 58 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 260,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 180,000× the energy of this one
  3. Around the size people start to feel M 3.0 16× the energy of this one
  4. This earthquake M 2.2 about 58 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 3 earthquakes of M5 or more within 50 km:

  1. 5.9 West of Downieville, California · 43 km S of this epicentre
  2. 5.7 2 km NNE of Canyondam, California · 36 km NNW of this epicentre
  3. 5.2 3 km N of Blairsden, California · 28 km ESE 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 39.8850, -120.9298. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Plumas County, CA 15 km (9 mi) NE earthquakes near Plumas County
Sierra County, CA 49 km (30 mi) SE earthquakes near Sierra County
Butte County, CA 63 km (39 mi) WSW earthquakes near Butte County
Nevada County, CA 67 km (41 mi) SSE earthquakes near Nevada County
Yuba County, CA 77 km (48 mi) SSW earthquakes near Yuba County
Placer County, CA 93 km (58 mi) S earthquakes near Placer County

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

Aftershocks so far

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

  1. 1.7 5km WNW of Hamilton Branch, CA
  2. 1.5 5km N of Almanor, CA
  3. 2.3 10km WNW of Little Grass Valley, CA
  4. 2.1 3km N of Canyondam, CA
  5. 1.5 5km E of Caribou, CA
  6. 2.0 2km E of Prattville, CA
  7. 1.8 4km NE of Prattville, CA
  8. 2.5 2km N of Prattville, CA
  9. 2.4 2km ENE of Prattville, CA
  10. 2.2 2km NW of Canyondam, CA
  11. 1.5 2 km SE of Spring Garden, California
  12. 1.7 2 km SSW of Crescent Mills, California
  13. 1.5 3 km WNW of Sierra City, California
  14. 2.0 3km SSW of East Shore, CA
  15. 2.2 9km E of Little Grass Valley, 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.