QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

8 km SW of Napa, CA

· 7.0 km deep · released about 6.6 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 30 kmSolano County 35 kmMarin County 42 kmContra Costa County 49 kmSonoma County 60 kmYolo County 62 kmAlameda County 76 kmSan Francisco County 84 kmSacramento County 90 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 1.6 (md)
Depth
7.0 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Napa County, 30 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1138 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 6.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.6 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 38.2418, -122.3358. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 30 km (18 mi) S of here earthquakes near Napa County
Solano County, CA 35 km (22 mi) W of here earthquakes near Solano County
Marin County, CA 42 km (26 mi) ENE of here earthquakes near Marin County
Contra Costa County, CA 49 km (31 mi) NW of here earthquakes near Contra Costa County
Sonoma County, CA 60 km (37 mi) ESE of here earthquakes near Sonoma County
Yolo County, CA 62 km (38 mi) SW of here earthquakes near Yolo County

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

Aftershocks so far

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

  1. 1.8 2 km ENE of Berkeley, CA
  2. 2.5 2 km ENE of Berkeley, CA
  3. 2.1 2 km E of Pacheco, CA
  4. 2.1 1 km E of Pinole, CA
  5. 1.6 6 km ESE of Santa Venetia, CA
  6. 2.0 1 km E of Pacheco, CA
  7. 1.8 1 km SSE of Pacheco, CA
  8. 2.0 2 km ENE of Berkeley, CA
  9. 1.8 3 km W of Orinda, CA
  10. 2.5 3 km NNW of Piedmont, CA
  11. 1.6 11 km ENE of Yountville, CA
  12. 1.8 6 km ESE of Santa Venetia, CA
  13. 1.5 6 km NNE of Orinda, CA
  14. 1.8 8 km SW of Calistoga, CA
  15. 1.8 11 km E of Yountville, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2019-10-15 — it released about 22,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.