QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

Earthquake near Covelo, CA

No earthquake was likely felt in Covelo in the 24 hours to 9:15 pm PST (05:15 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 2.3 earthquake was recorded 34 km (21 mi) east of Covelo, CA, at 5:45 am PDT on 8 June 2018 (12:45 UTC), 3.4 km deep.

USGS: 15km NW of Alder Springs, CA

5:45 am PDT, Jun 8, 2018 · · 3.4 km deep · released about 88 lb of TNT

10 km30 km60 km120 km N Glenn County 42 kmMendocino County 62 kmTehama County 68 kmLake County 72 kmColusa County 83 kmTrinity County 102 kmButte 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
5:45 am PDT on 8 June 2018 ()
Where
34 km (21 mi) east of Covelo, CA · earthquakes near Covelo
Magnitude
M 2.3 (md)
Depth
3.4 km below the surface
Felt
no reports yet
Nearest
Glenn County, 42 km ESE
Nearest mapped fault
Bartlett Springs fault system, 13 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 3078 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, 34 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.

How big was it?

This earthquake released about 88 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 170,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 120,000× the energy of this one
  3. Around the size people start to feel M 3.0 11× the energy of this one
  4. This earthquake M 2.3 about 88 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 15,000 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 39.7490, -122.8532. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Glenn County, CA 42 km (26 mi) ESE earthquakes near Glenn County
Mendocino County, CA 62 km (38 mi) SW earthquakes near Mendocino County
Tehama County, CA 68 km (42 mi) NE earthquakes near Tehama County
Lake County, CA 72 km (45 mi) S earthquakes near Lake County
Colusa County, CA 83 km (51 mi) SE earthquakes near Colusa County
Trinity County, CA 102 km (64 mi) NNW earthquakes near Trinity County

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

Aftershocks so far

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

  1. 1.9 17km SE of Lake Pillsbury, CA
  2. 1.9 17km ESE of Lake Pillsbury, CA
  3. 1.9 8km SSE of Lake Pillsbury, CA
  4. 2.5 20km NNW of Alder Springs, CA
  5. 1.6 20km NNW of Alder Springs, CA
  6. 2.1 20km NNW of Alder Springs, CA
  7. 1.9 7km NE of Brooktrails, CA
  8. 1.6 18km NNW of Covelo, CA
  9. 1.8 12km SE of Laytonville, CA
  10. 1.8 3km NW of Lake Pillsbury, CA
  11. 1.6 25km W of Rancho Tehama Reserve, CA
  12. 1.9 8km SSE of Lake Pillsbury, CA
  13. 2.1 14km NNE of Lake Pillsbury, CA
  14. 1.8 14km WNW of Lake Pillsbury, CA
  15. 1.8 37km NNW of Alder Springs, 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.