QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

7km ENE of Penngrove, CA

· 8.1 km deep · released about 12 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 31 kmMarin County 33 kmSonoma County 37 kmSolano County 57 kmContra Costa County 72 kmYolo County 72 kmSan Francisco County 76 kmLake County 88 kmAlameda County 96 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
Magnitude
M 1.7 (md)
Depth
8.1 km below the surface
Felt
no reports yet
Nearest
Napa County, 31 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3007 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 870,000× the energy of this one
  3. Around the size people start to feel M 3.0 78× the energy of this one
  4. This earthquake M 1.7 about 12 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.

Where

Epicentre 38.3218, -122.5932. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 31 km (19 mi) SW of here earthquakes near Napa County
Marin County, CA 33 km (20 mi) NNE of here earthquakes near Marin County
Sonoma County, CA 37 km (23 mi) SE of here earthquakes near Sonoma County
Solano County, CA 57 km (36 mi) W of here earthquakes near Solano County
Contra Costa County, CA 72 km (45 mi) NW of here earthquakes near Contra Costa County
Yolo County, CA 72 km (45 mi) WSW of here earthquakes near Yolo County

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

Aftershocks so far

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

  1. 2.2 3km SSW of Anderson Springs, CA
  2. 2.6 3km SSW of Anderson Springs, CA
  3. 1.9 3km SW of Anderson Springs, CA
  4. 1.6 2km ENE of Angwin, CA
  5. 2.2 5km E of Kenwood, CA
  6. 1.9 6km SW of St. Helena, CA
  7. 1.8 10km E of Healdsburg, CA
  8. 1.7 4km SW of Anderson Springs, CA
  9. 1.6 3km SSW of Anderson Springs, CA
  10. 1.7 4km NNW of Larkfield-Wikiup, CA
  11. 2.5 4km N of Santa Rosa, CA
  12. 2.3 4km N of Santa Rosa, CA
  13. 2.1 3km SW of Anderson Springs, CA
  14. 1.8 15km E of Angwin, CA
  15. 2.1 6km NE of Penngrove, 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.