Earthquake · reviewed by a seismologist
M 1.8md
8km W of Yountville, CA
- When
- Magnitude
- M 1.8 (md)
- Depth
- 7.8 km below the surface
- Felt
- no reports yet
- Nearest
- Napa County, 16 km NE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2777 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 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 900,000× the energy of this one
- Magna, Utah 2020 M 5.7 640,000× the energy of this one
- Around the size people start to feel M 3.0 57× the energy of this one
- This earthquake M 1.8 about 17 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 38.3980, -122.4505. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Napa County, CA | 16 km (10 mi) | SW of here | earthquakes near Napa County |
| Sonoma County, CA | 44 km (27 mi) | ESE of here | earthquakes near Sonoma County |
| Marin County, CA | 46 km (29 mi) | NE of here | earthquakes near Marin County |
| Solano County, CA | 47 km (29 mi) | WNW of here | earthquakes near Solano County |
| Yolo County, CA | 57 km (35 mi) | WSW of here | earthquakes near Yolo County |
| Contra Costa County, CA | 69 km (43 mi) | NW of here | earthquakes near Contra Costa County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
4 earthquakes have been recorded within 50 km since this one.
- 2.0 3km WNW of Anderson Springs, CA
- 2.0 12km NE of Napa, CA
- 1.7 3km S of Cobb, CA
- 1.6 3km SW of Anderson Springs, 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 4.2 on 2018-01-18 — it released about 3,800 times the energy of this one.
From the QuakeIndex catalogue, built from the USGS FDSN event service.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.