QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Boonville, CA

No earthquake was likely felt in Boonville in the 24 hours to 6:41 am PST (14:41 UTC). The last one was M 4.0, 65 km (41 mi) NNE, at 5:01 am PDT on 28 October 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Boonville

This page: a magnitude 1.8 earthquake was recorded 21 km (13 mi) north-northwest of Boonville, CA, at 1:31 pm PDT on 31 May 2022 (20:31 UTC), 1.7 km deep.

USGS: 21km NNW of Boonville, CA

1:31 pm PDT, May 31, 2022 · · 1.7 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Mendocino County 29 kmLake County 64 kmSonoma County 87 kmGlenn County 104 kmColusa 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
1:31 pm PDT on 31 May 2022 ()
Where
21 km (13 mi) north-northwest of Boonville, CA · earthquakes near Boonville
Magnitude
M 1.8 (md)
Depth
1.7 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 29 km N
Nearest mapped fault
Maacama fault, 23 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 1616 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 14 km (9 mi) from the epicentre. In Boonville, 21 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: Ukiah, Redwood Valley, Talmage, Willits.

How big was it?

This earthquake released about 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 4.4 on 2020-12-06 — about 6,900 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 · 34 km E 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 39.1745, -123.4810. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mendocino County, CA 29 km (18 mi) N earthquakes near Mendocino County
Lake County, CA 64 km (40 mi) E earthquakes near Lake County
Sonoma County, CA 87 km (54 mi) SE earthquakes near Sonoma County
Glenn County, CA 104 km (65 mi) ENE earthquakes near Glenn County
Colusa County, CA 107 km (67 mi) E earthquakes near Colusa County
Napa County, CA 125 km (77 mi) SE earthquakes near Napa 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. 1.7 5km ENE of Willits, CA
  2. 2.1 9km ESE of Willits, CA
  3. 1.6 14km WSW of Brooktrails, CA
  4. 1.6 12km W of Lake Pillsbury, CA
  5. 1.6 12km NNE of Point Arena, CA
  6. 1.8 12km WNW of Lake Pillsbury, CA
  7. 2.4 3km E of Willits, CA
  8. 1.7 5km ENE of Willits, CA
  9. 2.3 13km WNW of Redwood Valley, CA
  10. 2.3 13km W of Lake Pillsbury, CA
  11. 1.9 12km W of Lake Pillsbury, CA
  12. 1.8 14km N of Brooktrails, CA
  13. 1.6 16km NW of Lake Pillsbury, CA
  14. 1.5 10km ESE of Willits, CA
  15. 1.6 12km W 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.