QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

16 km NE of Potter Valley, California

· 11 km deep · released about 21 lb of TNT

10 km30 km60 km120 km N Mendocino County 39 kmLake County 42 kmGlenn County 54 kmColusa County 70 kmTehama County 101 kmSonoma County 101 kmNapa County 118 kmSutter County 119 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 1.9 (md)
Depth
11 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Mendocino County, 39 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3385 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 21 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 710,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
  3. Around the size people start to feel M 3.0 45× the energy of this one
  4. This earthquake M 1.9 about 21 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 39.4312, -122.9865. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 39 km (24 mi) E of here earthquakes near Mendocino County
Lake County, CA 42 km (26 mi) NNW of here earthquakes near Lake County
Glenn County, CA 54 km (33 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 70 km (44 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 101 km (63 mi) SW of here earthquakes near Tehama County
Sonoma County, CA 101 km (63 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

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

  1. 1.8 17 km NE of Upper Lake, California
  2. 1.5 19 km NNE of Upper Lake, California
  3. 1.5 9 km NE of Willits, California
  4. 1.5 15 km NE of Potter Valley, California
  5. 1.7 15 km NE of Potter Valley, California
  6. 1.9 15 km NE of Potter Valley, California
  7. 1.9 17 km NW of Elk Creek, California
  8. 1.6 8 km E of Willits, California
  9. 2.0 6 km ENE of Calpella, California
  10. 1.7 9 km ESE of Willits, California
  11. 1.6 19 km ENE of Potter Valley, California
  12. 1.7 20 km ENE of Potter Valley, California
  13. 1.5 28 km W of Paskenta, California
  14. 1.6 28 km W of Paskenta, California
  15. 1.5 18 km NE of Upper Lake, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 5.1 on 2016-08-10 — it released about 61,000 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.