QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

18km SE of Lake Pillsbury, CA

· 7.9 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 23 kmGlenn County 47 kmColusa County 50 kmMendocino County 57 kmSonoma County 88 kmNapa County 98 kmSutter County 99 kmTehama County 103 kmYolo County 104 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
7.9 km below the surface
Felt
no reports yet
Nearest
Lake County, 23 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3104 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 39.3082, -122.7947. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, CA 23 km (14 mi) N of here earthquakes near Lake County
Glenn County, CA 47 km (29 mi) SW of here earthquakes near Glenn County
Colusa County, CA 50 km (31 mi) WNW of here earthquakes near Colusa County
Mendocino County, CA 57 km (36 mi) ESE of here earthquakes near Mendocino County
Sonoma County, CA 88 km (55 mi) N of here earthquakes near Sonoma County
Napa County, CA 98 km (61 mi) NNW of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 2.1 20km ENE of Clearlake, CA
  2. 1.6 9km NNW of Redwood Valley, CA
  3. 1.8 6km SE of Lake Pillsbury, CA
  4. 1.9 18km NE of Upper Lake, CA
  5. 1.9 17km NE of Upper Lake, CA
  6. 1.6 13km WSW of Lakeport, CA
  7. 1.9 10km NW of Cobb, CA
  8. 1.8 17km NE of Nice, CA
  9. 2.0 4km NW of Redwood Valley, CA
  10. 1.6 7km SW of Lakeport, CA
  11. 1.9 2km WNW of Redwood Valley, CA
  12. 1.8 2km WNW of Redwood Valley, CA
  13. 3.7 3km WNW of Redwood Valley, CA
  14. 2.3 15km NW of Alder Springs, CA
  15. 2.9 14km NW of Alder Springs, 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 100,000 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.