QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

8km NNW of Sea Ranch, CA

· 4.9 km deep · released about 22 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Sonoma County 57 kmMendocino County 73 kmLake County 75 kmMarin County 104 kmNapa County 106 kmColusa County 118 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 1.9 (md)
Depth
4.9 km below the surface
Felt
no reports yet
Nearest
Sonoma County, 57 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2602 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 22 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 680,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 480,000× the energy of this one
  3. Around the size people start to feel M 3.0 43× the energy of this one
  4. This earthquake M 1.9 about 22 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 38.7738, -123.4970. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Sonoma County, CA 57 km (35 mi) WNW of here earthquakes near Sonoma County
Mendocino County, CA 73 km (46 mi) S of here earthquakes near Mendocino County
Lake County, CA 75 km (47 mi) WSW of here earthquakes near Lake County
Marin County, CA 104 km (64 mi) NW of here earthquakes near Marin County
Napa County, CA 106 km (66 mi) WNW of here earthquakes near Napa County
Colusa County, CA 118 km (73 mi) WSW of here earthquakes near Colusa County

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

Aftershocks so far

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

  1. 1.9 7km SSE of Talmage, CA
  2. 1.6 12km W of Lakeport, CA
  3. 1.5 14km ESE of Boonville, CA
  4. 2.1 12km S of Boonville, CA
  5. 1.7 13km WSW of Lakeport, CA
  6. 2.4 12km SE of Point Arena, CA
  7. 1.5 17km ESE of Boonville, CA
  8. 2.2 16km ESE of Boonville, CA
  9. 1.6 6km NE of Cloverdale, CA
  10. 1.8 16km ESE of Navarro Head, CA
  11. 1.9 19km NW of Cloverdale, CA
  12. 2.6 12km N of Point Arena, CA
  13. 2.2 12km N of Point Arena, CA
  14. 2.3 13km N of Point Arena, CA
  15. 1.7 10km NNE of Cloverdale, 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.