QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Laytonville, CA

No earthquake was likely felt in Laytonville in the 24 hours to 1:34 am PST (09:34 UTC). The last one was M 2.4, 13 km (8 mi) WSW, at 7:25 am PST on 4 November 2026, estimated intensity II (weak) in town. Every earthquake near Laytonville

This page: a magnitude 1.8 earthquake was recorded 4 km (3 mi) north of Laytonville, CA, at 11:52 pm PST on 6 December 2020 (07:52 UTC), 13 km deep.

USGS: 4km N of Laytonville, CA

11:52 pm PST, Dec 6, 2020 · · 13 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Mendocino County 33 kmLake County 94 kmGlenn County 94 kmTrinity County 107 kmHumboldt County 115 kmTehama County 116 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
11:52 pm PST on 6 December 2020 ()
Where
4 km (3 mi) north of Laytonville, CA · earthquakes near Laytonville
Magnitude
M 1.8 (md)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 33 km S
Nearest mapped fault
Maacama fault, 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2165 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Laytonville, 4 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Covelo.

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.

For this area

The largest earthquake within 50 km since 2016 was M 4.3 on 2019-04-29 — about 7,200 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.9 9 km S of Leggett, California · 22 km WNW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 39.7253, -123.4920. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mendocino County, CA 33 km (20 mi) S earthquakes near Mendocino County
Lake County, CA 94 km (58 mi) SE earthquakes near Lake County
Glenn County, CA 94 km (59 mi) E earthquakes near Glenn County
Trinity County, CA 107 km (67 mi) NNE earthquakes near Trinity County
Humboldt County, CA 115 km (72 mi) NNW earthquakes near Humboldt County
Tehama County, CA 116 km (72 mi) ENE earthquakes near Tehama County

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

Aftershocks so far

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

  1. 1.5 8km NNW of Redwood Valley, CA
  2. 1.5 12km N of Brooktrails, CA
  3. 1.6 26km N of Laytonville, CA
  4. 1.5 10km ESE of Willits, CA
  5. 2.1 11km SSE of Redway, CA
  6. 1.7 7km E of Willits, CA
  7. 1.6 10km SE of Laytonville, CA
  8. 2.4 10km SE of Willits, CA
  9. 2.0 13km WNW of Lake Pillsbury, CA
  10. 2.7 13km W of Lake Pillsbury, CA
  11. 1.9 10km ESE of Willits, CA
  12. 1.8 10km ESE of Willits, CA
  13. 1.8 22km SE of Covelo, CA
  14. 1.9 10km NNW of Redwood Valley, CA
  15. 1.8 10km ESE of Willits, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.