QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

13 km SSE of Tennant, CA

· 6.8 km deep · released about 40 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Siskiyou County 58 kmShasta County 81 kmModoc County 96 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
Siskiyou County, 58 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 271 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 40 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 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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 41.4773, -121.8567. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Siskiyou County, CA 58 km (36 mi) ESE of here earthquakes near Siskiyou County
Shasta County, CA 81 km (50 mi) N of here earthquakes near Shasta County
Modoc County, CA 96 km (59 mi) W of here earthquakes near Modoc County
Jackson County, OR 124 km (77 mi) SSE of here earthquakes near Jackson County
Lassen County, CA 134 km (83 mi) NW of here earthquakes near Lassen County
Trinity County, CA 140 km (87 mi) NE of here earthquakes near Trinity County

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

Aftershocks so far

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

  1. 2.0 13 km SSW of Tennant, CA
  2. 1.7 21 km NE of Big Bend, CA
  3. 1.8 14 km NNE of McCloud, CA
  4. 1.6 12 km N of McCloud, CA
  5. 2.1 13 km N of McCloud, CA
  6. 1.6 25 km NW of McArthur, CA
  7. 1.7 13 km NNE of McCloud, CA
  8. 1.9 3 km WNW of Mount Shasta, CA
  9. 1.8 31 km E of Tennant, CA
  10. 1.8 15 km NW of Big Bend, CA
  11. 1.9 24 km E of Tennant, 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.