QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

7 km NNE of Brooktrails, California

· -0.7 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 12 kmLake County 68 kmGlenn County 82 kmColusa County 102 kmSonoma County 115 kmTehama County 118 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
-0.7 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 12 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3487 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 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 39.5077, -123.3505. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 12 km (7 mi) NE of here earthquakes near Mendocino County
Lake County, CA 68 km (43 mi) NW of here earthquakes near Lake County
Glenn County, CA 82 km (51 mi) W of here earthquakes near Glenn County
Colusa County, CA 102 km (64 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 115 km (72 mi) NNW of here earthquakes near Sonoma County
Tehama County, CA 118 km (73 mi) SW of here earthquakes near Tehama 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. 1.7 25 km SE of Covelo, California
  2. 2.1 3 km NW of Redwood Valley, California
  3. 1.9 near the coast of Northern California
  4. 1.6 17 km ENE of Potter Valley, California
  5. 1.6 4 km NNE of Ukiah, California
  6. 1.8 8 km SSE of Laytonville, California
  7. 1.5 23 km NNE of Upper Lake, California
  8. 2.4 19 km N of Upper Lake, California
  9. 1.9 5 km E of Laytonville, California
  10. 1.8 21 km NNE of Upper Lake, California
  11. 2.0 12 km N of Philo, California
  12. 1.8 10 km NE of Philo, California
  13. 1.7 6 km E of Albion, California
  14. 1.7 8 km NE of Boonville, California
  15. 2.0 12 km WSW of Laytonville, 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.