QuakeIndex

Earthquake · automatic estimate, may change

M 0.7md

Earthquake near Cobb, CA

USGS: 4 km W of Cobb, CA

43 km (26 mi) N of Santa Rosa, CA · 120 km (75 mi) NNW of San Francisco, CA

3:49 am PDT, Oct 2, 2026 · · 2.7 km deep · released about 0.34 lb of TNT

10 km30 km60 km120 km N Lake County 31 kmSonoma County 36 kmNapa County 52 kmColusa County 60 kmYolo County 76 kmMarin County 86 kmMendocino County 89 kmGlenn County 92 kmSutter 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
3:49 am PDT on 2 October 2026 ()
Where
4 km (2 mi) W of Cobb, CA · earthquakes near Cobb
Magnitude
M 0.7 (md)
Depth
2.7 km below the surface
Felt
no reports yet
Nearest
Lake County, 31 km N
Nearest mapped fault
Konocti Bay fault, 8 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 15 hours ago

A magnitude 0.7 earthquake was recorded 4 km (2 mi) W of Cobb, CA, at 3:49 am PDT on 2 October 2026 (10:49 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Clear Lake Riviera, Middletown, Lower Lake, Hidden Valley Lake, Kelseyville, Clearlake.

How big was it?

This earthquake released about 0.34 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 1.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 2,800× the energy of this one
  4. This earthquake M 0.7 about 0.34 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 5.0 on 2016-12-14 — about 2,900,000 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 · 43 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 38.8265, -122.7645. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 31 km (19 mi) N earthquakes near Lake County
Sonoma County, CA 36 km (23 mi) SSW earthquakes near Sonoma County
Napa County, CA 52 km (32 mi) SE earthquakes near Napa County
Colusa County, CA 60 km (37 mi) NE earthquakes near Colusa County
Yolo County, CA 76 km (48 mi) ESE earthquakes near Yolo County
Marin County, CA 86 km (54 mi) S earthquakes near Marin County

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

Aftershocks so far

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

  1. 0.7 8 km NW of The Geysers, CA
  2. 0.5 6 km WNW of The Geysers, CA
  3. 0.9 8 km NW of The Geysers, CA
  4. 1.1 8 km NW of The Geysers, CA
  5. 1.1 8 km NW of The Geysers, CA
  6. 0.7 5 km NNW of The Geysers, CA
  7. 1.0 7 km WNW of The Geysers, CA
  8. 0.5 13 km ENE of Cloverdale, CA
  9. 1.0 7 km NW of The Geysers, CA
  10. 1.1 7 km NW of The Geysers, CA
  11. 1.0 8 km ESE of Cloverdale, CA
  12. 0.4 9 km NW of The Geysers, CA
  13. 0.8 8 km NW of The Geysers, CA
  14. 1.1 6 km WNW of The Geysers, CA
  15. 0.7 4 km W of Cobb, 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.