QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

1 km E of Johnsville, CA

· 6.0 km deep · released about 72 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sierra County 26 kmPlumas County 27 kmNevada County 54 kmPlacer County 80 kmButte County 80 kmYuba County 80 kmLassen County 104 kmStorey County 106 kmCarson City 106 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
Magnitude
M 2.3 (md)
Depth
6.0 km below the surface
Felt
no reports yet
Nearest
Sierra County, 26 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1054 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 72 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 210,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 150,000× the energy of this one
  3. Around the size people start to feel M 3.0 13× the energy of this one
  4. This earthquake M 2.3 about 72 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.

Where

Epicentre 39.7792, -120.6790. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Sierra County, CA 26 km (16 mi) NNW of here earthquakes near Sierra County
Plumas County, CA 27 km (17 mi) SSE of here earthquakes near Plumas County
Nevada County, CA 54 km (34 mi) N of here earthquakes near Nevada County
Placer County, CA 80 km (50 mi) N of here earthquakes near Placer County
Butte County, CA 80 km (50 mi) E of here earthquakes near Butte County
Yuba County, CA 80 km (50 mi) NE of here earthquakes near Yuba County

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

Aftershocks so far

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

  1. 2.9 0 km NNE of Whitehawk, CA
  2. 2.6 4 km S of Caribou, CA
  3. 2.3 4 km S of Cromberg, CA
  4. 2.1 12 km W of La Porte, CA
  5. 2.1 5 km SE of Canyondam, CA
  6. 1.8 6 km WSW of Greenville, California
  7. 1.5 9 km SSE of Sierraville, California
  8. 1.7 4 km SW of Sierra Brooks, California
  9. 2.1 6 km W of Twain, CA
  10. 1.7 7 km ENE of East Quincy, California
  11. 2.2 4 km NNW of Spring Garden, CA
  12. 2.2 5 km NNE of East Quincy, CA
  13. 1.5 13 km NE of Lake Davis, California
  14. 3.4 4 km ENE of East Quincy, CA
  15. 2.0 4 km SW of Whitehawk, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.7 on 2021-05-07 — it released about 4,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.