QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

9 km ESE of Redwood Valley, CA

· 6.5 km deep · released about 10 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 34 kmMendocino County 36 kmGlenn County 72 kmColusa County 75 kmSonoma County 81 kmNapa County 106 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 1.7 (md)
Depth
6.5 km below the surface
Felt
no reports yet
Nearest
Lake County, 34 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 42 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 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 95× the energy of this one
  4. This earthquake M 1.7 about 10 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 39.2423, -123.1015. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, CA 34 km (21 mi) WNW of here earthquakes near Lake County
Mendocino County, CA 36 km (22 mi) SE of here earthquakes near Mendocino County
Glenn County, CA 72 km (45 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 75 km (46 mi) W of here earthquakes near Colusa County
Sonoma County, CA 81 km (50 mi) N of here earthquakes near Sonoma County
Napa County, CA 106 km (66 mi) NW of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 1.8 10 km N of Lake Pillsbury, CA
  2. 2.6 10 km N of Lake Pillsbury, CA
  3. 1.5 18 km SE of Lake Pillsbury, CA
  4. 1.7 8 km NW of Redwood Valley, CA
  5. 1.8 19 km NE of Upper Lake, CA
  6. 1.5 11 km N of Redwood Valley, CA
  7. 1.8 8 km NW of Redwood Valley, CA
  8. 1.7 9 km ESE of Lake Pillsbury, CA
  9. 1.6 8 km NW of Redwood Valley, CA
  10. 1.7 12 km ESE of Willits, CA
  11. 1.7 8 km NW of Redwood Valley, CA
  12. 1.9 8 km NW of Redwood Valley, CA
  13. 1.7 9 km N of Redwood Valley, CA
  14. 1.7 10 km WNW of Cobb, CA
  15. 1.5 12 km WNW of Cobb, 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 5.6 on 2026-06-24 — it released about 730,000 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.