QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

15km WNW of Lake Pillsbury, CA

· 3.2 km deep · released about 6.2 lb of TNT

10 km30 km60 km120 km N Mendocino County 29 kmLake County 52 kmGlenn County 63 kmColusa County 82 kmTehama County 104 kmSonoma County 107 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 1.5 (md)
Depth
3.2 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 29 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1417 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 6.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.5 about 6.2 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 39.4778, -123.1137. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 29 km (18 mi) E of here earthquakes near Mendocino County
Lake County, CA 52 km (32 mi) NW of here earthquakes near Lake County
Glenn County, CA 63 km (39 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 82 km (51 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 104 km (65 mi) SW of here earthquakes near Tehama County
Sonoma County, CA 107 km (67 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

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

  1. 2.1 4km W of Ukiah, CA
  2. 2.6 4km W of Ukiah, CA
  3. 2.0 5km W of Ukiah, CA
  4. 1.6 15km ENE of Nice, CA
  5. 1.6 1km E of Lake Pillsbury, CA
  6. 1.7 5km WSW of Laytonville, CA
  7. 2.3 8km NNE of Laytonville, CA
  8. 1.5 9km NNE of Redwood Valley, CA
  9. 1.8 22km NNW of Lake Pillsbury, CA
  10. 1.6 8km SSE of Lake Pillsbury, CA
  11. 1.6 9km ESE of Lake Pillsbury, CA
  12. 1.8 13km W of Lake Pillsbury, CA
  13. 2.1 12km NW of Alder Springs, CA
  14. 1.8 24km SE of Covelo, CA
  15. 1.7 6km ESE of Lake Pillsbury, 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 210,000 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.