QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Ukiah, CA

Yes: an earthquake was likely felt in Ukiah in the last 24 hours. M 1.5, 10 km (6 mi) NE of Ukiah, at 12:31 pm PST on 11 November 2026 (20:31 UTC); the estimated shaking in Ukiah was intensity II (weak). Every earthquake near Ukiah

This page: a magnitude 2.1 earthquake was recorded 15 km (9 mi) south-southeast of Ukiah, CA, at 6:42 am PDT on 5 November 2016 (13:42 UTC), 6.1 km deep. 1 person has reported feeling it to USGS.

USGS: 6 km N of Hopland, California

75 km (46 mi) NNW of Santa Rosa, CA

6:42 am PDT, Nov 5, 2016 · · 6.1 km deep · released about 47 lb of TNT

10 km30 km60 km120 km N Lake County 33 kmMendocino County 52 kmSonoma County 59 kmColusa County 77 kmGlenn County 88 kmNapa County 90 kmYolo County 112 kmMarin County 114 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
6:42 am PDT on 5 November 2016 ()
Where
15 km (9 mi) south-southeast of Ukiah, CA · earthquakes near Ukiah
Magnitude
M 2.1 (md)
Depth
6.1 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Lake County, 33 km ENE
Nearest mapped fault
Maacama fault, 2 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 3561 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 17 km (11 mi) from the epicentre. In Ukiah, 15 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: Ukiah 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 47 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 320,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 20× the energy of this one
  4. This earthquake M 2.1 about 47 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 28,000 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 · 9 km N 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 39.0350, -123.1158. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 33 km (21 mi) ENE earthquakes near Lake County
Mendocino County, CA 52 km (33 mi) NNW earthquakes near Mendocino County
Sonoma County, CA 59 km (37 mi) SSE earthquakes near Sonoma County
Colusa County, CA 77 km (48 mi) ENE earthquakes near Colusa County
Glenn County, CA 88 km (55 mi) NE earthquakes near Glenn County
Napa County, CA 90 km (56 mi) SE earthquakes near Napa County

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

Aftershocks so far

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

  1. 2.4 6 km W of Cobb, California
  2. 1.5 9 km W of Cobb, California
  3. 1.5 4 km S of Cobb, California
  4. 1.7 7 km W of Cobb, California
  5. 2.0 7 km W of Cobb, California
  6. 1.5 6 km ENE of Cloverdale, California
  7. 1.8 19 km NNE of Upper Lake, California
  8. 1.9 5 km WNW of Cobb, California
  9. 1.5 9 km WNW of Cobb, California
  10. 1.9 6 km W of Cobb, California
  11. 1.6 7 km S of Cobb, California
  12. 1.7 8 km NE of Boonville, California
  13. 1.6 3 km S of Cobb, California
  14. 1.9 3 km SSW of Cobb, California
  15. 1.8 3 km S of Cobb, California

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.