Earthquake · automatic estimate, may change
M 1.7md
Earthquake near Santa Rosa, CA
USGS: 3 km SSW of Anderson Springs, CA
34 km (21 mi) N of Santa Rosa, CA · 111 km (69 mi) NNW of San Francisco, CA
- When
- 9:30 pm PDT on 30 September 2026 ()
- Where
- 34 km (21 mi) N of Santa Rosa, CA · earthquakes near Santa Rosa
- Magnitude
- M 1.7 (md)
- Depth
- 2.0 km below the surface
- Felt
- no reports yet
- Nearest
- Sonoma County, 31 km SW
- Nearest mapped fault
- Maacama fault, 11 km from its surface trace — near is not the same as on
- Status
- Automatic — a machine’s first estimate, which may change
USGS · last changed by USGS · we first saw it 2 days ago
A magnitude 1.7 earthquake was recorded 34 km (21 mi) N of Santa Rosa, CA, at 9:30 pm PDT on 30 September 2026 (04:30 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
Earthquakes near other towns within 30 km: Middletown, Cobb, Hidden Valley Lake, Lower Lake, Healdsburg, Calistoga.
How big was it?
This earthquake released about 9.6 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.
- Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
- Around the size people start to feel M 3.0 99× the energy of this one
- This earthquake M 1.7 about 9.6 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.
For this area
The largest earthquake within 50 km since 2016 was M 5.0 on 2016-12-14 — about 100,000 times the energy of this one.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 5.3 3 km E of Bloomfield, California · 49 km S of this epicentre
- 5.3 Northern California · 49 km SSW of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 38.7482, -122.7040. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Sonoma County, CA | 31 km (20 mi) | SW | earthquakes near Sonoma County |
| Lake County, CA | 40 km (25 mi) | N | earthquakes near Lake County |
| Napa County, CA | 42 km (26 mi) | SE | earthquakes near Napa County |
| Colusa County, CA | 63 km (39 mi) | NE | earthquakes near Colusa County |
| Yolo County, CA | 70 km (43 mi) | E | earthquakes near Yolo County |
| Marin County, CA | 78 km (48 mi) | S | earthquakes near Marin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
60 earthquakes have been recorded within 50 km since this one.
- 0.5 13 km ENE of Cloverdale, CA
- 1.0 7 km NW of The Geysers, CA
- 1.1 7 km NW of The Geysers, CA
- 1.0 8 km ESE of Cloverdale, CA
- 0.4 9 km NW of The Geysers, CA
- 0.8 8 km NW of The Geysers, CA
- 1.1 6 km WNW of The Geysers, CA
- 0.7 4 km W of Cobb, CA
- 0.3 6 km NW of The Geysers, CA
- 0.7 4 km W of Cobb, CA
- 1.4 2 km NE of The Geysers, CA
- 0.7 6 km NW of The Geysers, CA
- 0.7 7 km WNW of Cobb, CA
- 1.6 7 km WNW of Cobb, CA
- 0.8 8 km NW 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.
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.