QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

Earthquake near Covelo, CA

No earthquake was likely felt in Covelo in the 24 hours to 10:23 pm PST (06:23 UTC). The last one was M 2.2, 9 km (6 mi) N, at 3:31 pm PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near Covelo

This page: a magnitude 2.4 earthquake was recorded 9 km (5 mi) west of Covelo, CA, at 9:48 am PDT on 17 July 2020 (16:48 UTC), 4.5 km deep.

USGS: 9km W of Covelo, CA

9:48 am PDT, Jul 17, 2020 · · 4.5 km deep · released about 110 lb of TNT

10 km30 km60 km120 km N Mendocino County 40 kmGlenn County 84 kmLake County 92 kmTrinity County 98 kmTehama County 103 kmHumboldt County 113 kmColusa County 117 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
9:48 am PDT on 17 July 2020 ()
Where
9 km (5 mi) west of Covelo, CA · earthquakes near Covelo
Magnitude
M 2.4 (md)
Depth
4.5 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 40 km S
Nearest mapped fault
Bartlett Springs fault system, 4 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 2308 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 20 km (12 mi) from the epicentre. In Covelo, 9 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.

Likely felt in: Covelo 9 km, intensity II · Laytonville 16 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 110 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 95,000× the energy of this one
  3. Around the size people start to feel M 3.0 8.5× the energy of this one
  4. This earthquake M 2.4 about 110 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 2017-12-14 — about 660 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 · 33 km W 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 39.7893, -123.3527. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mendocino County, CA 40 km (25 mi) S earthquakes near Mendocino County
Glenn County, CA 84 km (52 mi) ESE earthquakes near Glenn County
Lake County, CA 92 km (57 mi) SE earthquakes near Lake County
Trinity County, CA 98 km (61 mi) NNE earthquakes near Trinity County
Tehama County, CA 103 km (64 mi) ENE earthquakes near Tehama County
Humboldt County, CA 113 km (70 mi) NNW earthquakes near Humboldt County

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

Aftershocks so far

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

  1. 1.7 11km SE of Willits, CA
  2. 1.7 11km NNW of Redwood Valley, CA
  3. 1.6 11km NNW of Redwood Valley, CA
  4. 2.0 11km NNW of Redwood Valley, CA
  5. 1.6 10km SE of Willits, CA
  6. 1.5 11km NNW of Redwood Valley, CA
  7. 1.7 11km NNW of Redwood Valley, CA
  8. 2.5 11km NNW of Redwood Valley, CA
  9. 1.8 10km ESE of Willits, CA
  10. 1.7 11km ESE of Willits, CA
  11. 1.5 20km NW of Lake Pillsbury, CA
  12. 2.0 10km ESE of Willits, CA
  13. 2.0 11km ESE of Willits, CA
  14. 2.5 10km ESE of Willits, CA
  15. 2.0 10km SE 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.