QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

Earthquake near Redwood Valley, CA

No earthquake was likely felt in Redwood Valley in the 24 hours to 3:26 pm PST (23:26 UTC). The last one was M 1.5, 7 km (5 mi) SE, at 12:31 pm PST on 11 November 2026, estimated intensity II (weak) in town. Every earthquake near Redwood Valley

This page: a magnitude 2.6 earthquake was recorded 6 km (4 mi) east-southeast of Redwood Valley, CA, at 7:46 pm PDT on 8 July 2020 (02:46 UTC), 5.2 km deep. 41 people have reported feeling it to USGS.

USGS: 6km ESE of Redwood Valley, CA

97 km (60 mi) NNW of Santa Rosa, CA

7:46 pm PDT, Jul 8, 2020 · · 5.2 km deep · released about 220 lb of TNT

10 km30 km60 km120 km N Mendocino County 33 kmLake County 37 kmGlenn County 74 kmColusa County 77 kmSonoma County 83 kmNapa County 108 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
7:46 pm PDT on 8 July 2020 ()
Where
6 km (4 mi) east-southeast of Redwood Valley, CA · earthquakes near Redwood Valley
Magnitude
M 2.6 (md)
Depth
5.2 km below the surface
Felt
41 reports · strongest reported intensity IV
Nearest
Mendocino County, 33 km NW
Nearest mapped fault
Maacama fault, 7 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 2215 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 23 km (14 mi) from the epicentre. In Redwood Valley, 6 km away, the estimate is intensity III (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: Ukiah 13 km, intensity II · Upper Lake 21 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 68,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 48,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.3× the energy of this one
  4. This earthquake M 2.6 about 220 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 5.1 on 2016-08-10 — about 5,800 times the energy of this one.

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

  1. 5.2 6 km ESE of Talmage, California · 16 km S 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 39.2537, -123.1305. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mendocino County, CA 33 km (21 mi) NW earthquakes near Mendocino County
Lake County, CA 37 km (23 mi) ESE earthquakes near Lake County
Glenn County, CA 74 km (46 mi) ENE earthquakes near Glenn County
Colusa County, CA 77 km (48 mi) E earthquakes near Colusa County
Sonoma County, CA 83 km (52 mi) SSE earthquakes near Sonoma County
Napa County, CA 108 km (67 mi) SE earthquakes near Napa County

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

Aftershocks so far

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

  1. 1.5 14km NNE of Brooktrails, CA
  2. 1.7 21km SE of Covelo, CA
  3. 2.0 11km NE of Cloverdale, CA
  4. 2.1 20km NNW of Lake Pillsbury, CA
  5. 1.6 9km NNW of Redwood Valley, CA
  6. 1.8 9km E of Redwood Valley, CA
  7. 2.0 20km NE of Brooktrails, CA
  8. 1.6 8km NNE of Redwood Valley, CA
  9. 1.6 15km ESE of Navarro Head, CA
  10. 1.9 20km NNW of Lake Pillsbury, CA
  11. 1.6 18km SE of Lake Pillsbury, CA
  12. 1.9 15km WSW of Lakeport, CA
  13. 1.8 12km SE of Talmage, CA
  14. 1.9 18km NW of Lake Pillsbury, CA
  15. 2.2 20km NNW 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.

On USGS

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