QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

11km N of Lake Pillsbury, CA

· 4.1 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 42 kmLake County 49 kmGlenn County 49 kmColusa County 73 kmTehama County 93 kmSonoma County 110 kmButte 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
4.1 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Mendocino County, 42 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1511 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 39.5103, -122.9665. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 42 km (26 mi) ENE of here earthquakes near Mendocino County
Lake County, CA 49 km (30 mi) NNW of here earthquakes near Lake County
Glenn County, CA 49 km (31 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 73 km (45 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 93 km (58 mi) SW of here earthquakes near Tehama County
Sonoma County, CA 110 km (68 mi) N of here earthquakes near Sonoma County

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

Aftershocks so far

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

  1. 1.6 10km N of Lake Pillsbury, CA
  2. 1.5 12km E of Redwood Valley, CA
  3. 1.8 9km N of Lake Pillsbury, CA
  4. 1.8 7km ENE of Laytonville, CA
  5. 1.8 18km NE of Upper Lake, CA
  6. 1.8 7km NW of Stony Gorge Reservoir, CA
  7. 1.6 4km S of Redwood Valley, CA
  8. 1.8 8km NW of Redwood Valley, CA
  9. 1.8 5km SE of Lake Pillsbury, CA
  10. 1.8 2km E of Willits, CA
  11. 2.9 13km WNW of Alder Springs, CA
  12. 2.8 14km WNW of Alder Springs, CA
  13. 2.0 13km WNW of Alder Springs, CA
  14. 2.4 14km WNW of Alder Springs, CA
  15. 1.5 7km ENE of Brooktrails, 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 5.1 on 2016-08-10 — it released about 95,000 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.