QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7md

15 km NNW of Susanville, CA

· 7.3 km deep · released about 320 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lassen County 20 kmPlumas County 63 kmWashoe County 89 kmSierra County 109 kmShasta County 116 kmModoc County 116 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 2.7 (md)
Depth
7.3 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Lassen County, 20 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 179 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 320 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 48,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 34,000× the energy of this one
  3. Around the size people start to feel M 3.0 3× the energy of this one
  4. This earthquake M 2.7 about 320 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 40.5470, -120.6938. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lassen County, CA 20 km (12 mi) SSW of here earthquakes near Lassen County
Plumas County, CA 63 km (39 mi) N of here earthquakes near Plumas County
Washoe County, NV 89 km (56 mi) WSW of here earthquakes near Washoe County
Sierra County, CA 109 km (68 mi) N of here earthquakes near Sierra County
Shasta County, CA 116 km (72 mi) ESE of here earthquakes near Shasta County
Modoc County, CA 116 km (72 mi) S of here earthquakes near Modoc County

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

Aftershocks so far

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

  1. 1.7 4 km NE of Canyondam, CA
  2. 1.8 11 km NNE of Chester, CA
  3. 2.2 15 km NNW of Susanville, CA
  4. 1.8 13 km NNW of Susanville, CA
  5. 2.1 16 km NE of Litchfield, California
  6. 2.9 14 km NNW of Susanville, CA
  7. 2.0 14 km NNW of Susanville, CA
  8. 2.2 3 km SE of Johnstonville, CA
  9. 1.9 14 km NNW of Susanville, CA
  10. 1.8 14 km NNW of Susanville, CA
  11. 1.9 4 km WSW of Hamilton Branch, CA
  12. 1.6 13 km NNW of Susanville, CA
  13. 1.9 14 km NNW of Susanville, CA
  14. 2.7 15 km NNW of Susanville, CA
  15. 2.1 15 km NNW of Susanville, 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 4.7 on 2025-12-29 — it released about 1,100 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.