QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

34 km SSE of Tennant, CA

· 9.2 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Shasta County 74 kmSiskiyou County 78 kmModoc County 82 kmLassen County 112 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 1.8 (md)
Depth
9.2 km below the surface
Felt
no reports yet
Nearest
Shasta County, 74 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 256 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 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 41.3575, -121.6465. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Shasta County, CA 74 km (46 mi) NNE of here earthquakes near Shasta County
Siskiyou County, CA 78 km (49 mi) ESE of here earthquakes near Siskiyou County
Modoc County, CA 82 km (51 mi) WSW of here earthquakes near Modoc County
Lassen County, CA 112 km (69 mi) NW of here earthquakes near Lassen County
Jackson County, OR 145 km (90 mi) SE of here earthquakes near Jackson County

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

Aftershocks so far

30 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. 1.6 7 km NNE of Burney, CA
  6. 2.1 13 km N of McCloud, CA
  7. 1.6 25 km NW of McArthur, CA
  8. 1.7 13 km NNE of McCloud, CA
  9. 1.8 31 km E of Tennant, CA
  10. 1.8 15 km NW of Big Bend, CA
  11. 2.1 10 km N of Burney, CA
  12. 2.2 10 km NE of Burney, CA
  13. 1.9 24 km E of Tennant, CA
  14. 2.1 13 km SSE of Tennant, CA
  15. 1.8 14 km NNE of McCloud, 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 5.0 on 2023-09-08 — it released about 55,000 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.