QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

Earthquake near Cobb, CA

Yes: an earthquake was likely felt in Cobb in the last 24 hours. M 1.6, 4 km (2 mi) W of Cobb, at 1:30 pm PST on 11 November 2026 (21:30 UTC); the estimated shaking in Cobb was intensity II (weak). Every earthquake near Cobb

This page: a magnitude 3.2 earthquake was recorded 5 km (3 mi) southwest of Cobb, CA, at 10:58 am PDT on 30 October 2016 (17:58 UTC), 2.0 km deep. 14 people have reported feeling it to USGS.

USGS: 4 km SW of Cobb, California

39 km (24 mi) N of Santa Rosa, CA · 116 km (72 mi) NNW of San Francisco, CA

10:58 am PDT, Oct 30, 2016 · · 2.0 km deep · released about 1.1 tons of TNT

10 km30 km60 km120 km N Sonoma County 33 kmLake County 35 kmNapa County 49 kmColusa County 62 kmYolo County 76 kmMarin County 82 kmSolano County 92 kmMendocino County 92 kmGlenn County 95 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
10:58 am PDT on 30 October 2016 ()
Where
5 km (3 mi) southwest of Cobb, CA · earthquakes near Cobb
Magnitude
M 3.2 (ml)
Depth
2.0 km below the surface
Felt
14 reports · strongest reported intensity IV
Nearest
Sonoma County, 33 km SSW
Nearest mapped fault
Maacama fault, 11 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 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 48 km (30 mi) from the epicentre. In Cobb, 5 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: Cobb 5 km, intensity III · Clearlake 22 km, intensity II · Healdsburg 22 km, intensity II · Cloverdale 22 km, intensity II · Windsor 28 km, intensity II · Calistoga 28 km, intensity II · Lakeport 31 km, intensity II · Angwin 36 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 160,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,200× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,100× the energy of this one
  4. This earthquake M 3.2 about 1.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.2× more

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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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

  1. 5.2 6 km ESE of Talmage, California · 46 km NW 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 38.7917, -122.7613. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sonoma County, CA 33 km (20 mi) SSW earthquakes near Sonoma County
Lake County, CA 35 km (22 mi) N earthquakes near Lake County
Napa County, CA 49 km (31 mi) SE earthquakes near Napa County
Colusa County, CA 62 km (39 mi) NE earthquakes near Colusa County
Yolo County, CA 76 km (47 mi) E earthquakes near Yolo County
Marin County, CA 82 km (51 mi) S earthquakes near Marin County

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

Aftershocks so far

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

  1. 1.7 1 km NW of Middletown, California
  2. 1.6 6 km NE of Cloverdale, California
  3. 1.8 6 km ENE of Cloverdale, California
  4. 1.7 9 km NNE of Hopland, California
  5. 2.1 2 km SSW of Cobb, California
  6. 2.0 10 km WNW of Cobb, California
  7. 1.7 10 km W of Cobb, California
  8. 1.6 5 km WNW of Cobb, California
  9. 1.5 4 km SSW of Cobb, California
  10. 1.8 7 km S of Cobb, California
  11. 2.4 5 km SW of Cobb, California
  12. 2.0 Northern California
  13. 1.9 5 km WNW of Cobb, California
  14. 2.0 3 km SSW of Cobb, California
  15. 1.8 3 km SSW 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.