QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

7km N of Greenhorn, CA

· 6.8 km deep · released about 37 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Plumas County 8 kmSierra County 47 kmNevada County 74 kmButte County 81 kmLassen County 84 kmYuba County 93 kmPlacer County 100 kmStorey County 119 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 2.1 (md)
Depth
6.8 km below the surface
Felt
no reports yet
Nearest
Plumas County, 8 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1866 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 37 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 5.8 410,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 290,000× the energy of this one
  3. Around the size people start to feel M 3.0 26× the energy of this one
  4. This earthquake M 2.1 about 37 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 39.9650, -120.7365. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Plumas County, CA 8 km (5 mi) ESE of here earthquakes near Plumas County
Sierra County, CA 47 km (29 mi) NNW of here earthquakes near Sierra County
Nevada County, CA 74 km (46 mi) N of here earthquakes near Nevada County
Butte County, CA 81 km (50 mi) ENE of here earthquakes near Butte County
Lassen County, CA 84 km (52 mi) S of here earthquakes near Lassen County
Yuba County, CA 93 km (58 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

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

  1. 1.6 4km N of Canyondam, CA
  2. 2.1 4km SE of Meadow Valley, CA
  3. 2.3 5km ENE of East Quincy, CA
  4. 2.1 16km WSW of Loyalton, CA
  5. 2.1 16km WSW of Loyalton, CA
  6. 1.6 16km WSW of Loyalton, CA
  7. 2.2 15km WSW of Loyalton, CA
  8. 2.4 16km WSW of Loyalton, CA
  9. 3.3 16km WSW of Loyalton, CA
  10. 2.7 16km WSW of Loyalton, CA
  11. 1.6 2 km WNW of Sierraville, California
  12. 2.1 16km WSW of Loyalton, CA
  13. 1.5 5km N of Almanor, CA
  14. 2.3 10km WNW of Little Grass Valley, CA
  15. 2.1 3km N of Canyondam, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2016-08-04 — it released about 4,300 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.