Earthquake · reviewed by a seismologist
M 2.1md
12km E of Angwin, CA
- When
- Magnitude
- M 2.1 (md)
- Depth
- -0.2 km below the surface
- Felt
- 3 reports · strongest reported intensity II
- Nearest
- Napa County, 5 km SSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2897 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 3 people have reported feeling it to USGS.
How big was it?
This earthquake released about 38 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.
- Mineral, Virginia 2011 M 5.8 390,000× the energy of this one
- Magna, Utah 2020 M 5.7 280,000× the energy of this one
- Around the size people start to feel M 3.0 25× the energy of this one
- This earthquake M 2.1 about 38 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 38.5542, -122.3095. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Napa County, CA | 5 km (3 mi) | NNE of here | earthquakes near Napa County |
| Yolo County, CA | 38 km (24 mi) | WSW of here | earthquakes near Yolo County |
| Solano County, CA | 45 km (28 mi) | NW of here | earthquakes near Solano County |
| Sonoma County, CA | 54 km (33 mi) | E of here | earthquakes near Sonoma County |
| Marin County, CA | 68 km (42 mi) | NE of here | earthquakes near Marin County |
| Colusa County, CA | 70 km (43 mi) | S of here | earthquakes near Colusa 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.
- 1.5 2km NNW of The Geysers, CA
- 1.9 3km SW of Anderson Springs, CA
- 1.7 10km SW of The Geysers, CA
- 1.6 1km NE of The Geysers, CA
- 1.6 3km SW of Anderson Springs, CA
- 1.9 1km NE of The Geysers, CA
- 1.5 8km SW of Calistoga, CA
- 2.4 2km E of The Geysers, CA
- 1.7 2km W of Anderson Springs, CA
- 1.7 8km ENE of Larkfield-Wikiup, CA
- 1.7 2km SSW of Anderson Springs, CA
- 1.6 4km NE of Vallejo, CA
- 1.9 3km W of Cobb, CA
- 1.5 4km NE of Saint Helena, CA
- 2.1 3km ENE 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.
For this area
The largest earthquake within 50 km in our catalogue was M 4.2 on 2018-01-18 — it released about 1,700 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.