QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Talmage, CA

Yes: an earthquake was likely felt in Talmage in the last 24 hours. M 1.5, 3 km (2 mi) NE of Talmage, at 3:26 am PST on 12 November 2026 (11:26 UTC); the estimated shaking in Talmage was intensity II (weak). Every earthquake near Talmage

This page: a magnitude 2.1 earthquake was recorded 12 km (7 mi) southeast of Talmage, CA, at 4:14 am PDT on 12 October 2021 (11:14 UTC), 3.8 km deep.

USGS: 12km SE of Talmage, CA

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

4:14 am PDT, Oct 12, 2021 · · 3.8 km deep · released about 49 lb of TNT

10 km30 km60 km120 km N Lake County 30 kmMendocino County 52 kmSonoma County 60 kmColusa County 75 kmGlenn County 85 kmNapa County 89 kmYolo County 111 kmMarin County 115 kmSutter County 120 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
4:14 am PDT on 12 October 2021 ()
Where
12 km (7 mi) southeast of Talmage, CA · earthquakes near Talmage
Magnitude
M 2.1 (md)
Depth
3.8 km below the surface
Felt
no reports yet
Nearest
Lake County, 30 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 1857 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 Talmage, 12 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: Lakeport 15 km, intensity II · 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 49 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 5.8 310,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 220,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 49 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 27,000 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 · 8 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 39.0487, -123.0893. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, CA 30 km (19 mi) ENE earthquakes near Lake County
Mendocino County, CA 52 km (33 mi) NW earthquakes near Mendocino County
Sonoma County, CA 60 km (37 mi) SSE earthquakes near Sonoma County
Colusa County, CA 75 km (47 mi) ENE earthquakes near Colusa County
Glenn County, CA 85 km (53 mi) NE earthquakes near Glenn County
Napa County, CA 89 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

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

  1. 1.6 12km WNW of Redwood Valley, CA
  2. 1.6 1km NNW of The Geysers, CA
  3. 1.9 7km NW of The Geysers, CA
  4. 1.6 7km NW of The Geysers, CA
  5. 1.7 18km SE of Lake Pillsbury, CA
  6. 2.0 3km SSW of Anderson Springs, CA
  7. 2.9 2km SW of Anderson Springs, CA
  8. 1.8 6km W of Cobb, CA
  9. 1.8 5km NNW of The Geysers, CA
  10. 1.7 10km WNW of The Geysers, CA
  11. 1.5 3km NNW of The Geysers, CA
  12. 2.4 2km N of The Geysers, CA
  13. 1.7 6km NNW of The Geysers, CA
  14. 1.8 6km NW of The Geysers, CA
  15. 1.8 6km NW of The Geysers, 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.