QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

22km ENE of Montague, CA

· 6.5 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Siskiyou County 34 kmJackson County 71 kmKlamath County 109 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
6.5 km below the surface
Felt
no reports yet
Nearest
Siskiyou County, 34 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2376 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 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 41.8343, -122.2987. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Siskiyou County, CA 34 km (21 mi) NE of here earthquakes near Siskiyou County
Jackson County, OR 71 km (44 mi) SSE of here earthquakes near Jackson County
Klamath County, OR 109 km (68 mi) SSW of here earthquakes near Klamath County
Shasta County, CA 121 km (75 mi) N of here earthquakes near Shasta County
Josephine County, OR 122 km (76 mi) ESE of here earthquakes near Josephine County

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

Aftershocks so far

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

  1. 2.0 13 km SSW of Tennant, CA
  2. 2.0 26 km ENE of Hornbrook, CA
  3. 2.0 19 km SSW of Ashland, Oregon
  4. 1.9 16 km SSW of Tennant, CA
  5. 1.8 16 km SSW of Tennant, CA
  6. 2.6 23 km WSW of Mount Hebron, CA
  7. 1.6 23 km WSW of Klamath Falls, Oregon
  8. 2.1 4 km SW of Tennant, CA
  9. 1.6 4 km SW of Tennant, CA
  10. 2.5 6 km NW of Macdoel, CA
  11. 2.4 8 km SSW of Tennant, CA
  12. 1.5 22 km E of Ashland, Oregon
  13. 1.9 24 km E of Hornbrook, CA
  14. 1.6 20 km E of Hornbrook, California
  15. 1.8 18 km E of Hornbrook, 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.

On USGS

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