Earthquake · automatic estimate, may change
M 1.7md
Earthquake near San Ramon, CA
No earthquake was likely felt in San Ramon in the 24 hours to 3:46 pm PDT (22:46 UTC). The last one was M 2.4, 4 km (3 mi) SE, at 4:29 pm PDT on 19 October 2026, estimated intensity III (weak) in town; 5 felt reports to USGS. Every earthquake near San Ramon
This page: a magnitude 1.7 earthquake was recorded in San Ramon, CA, at 7:35 pm PDT on 18 October 2026 (02:35 UTC), 8.7 km deep. The magnitude and location are an automatic first estimate and may change.
USGS: 1 km SW of San Ramon, CA
in San Ramon, CA · 38 km (24 mi) E of San Francisco, CA
- When
- 7:35 pm PDT on 18 October 2026 ()
- Where
- in San Ramon, CA · earthquakes near San Ramon
- Magnitude
- M 1.7 (md)
- Depth
- 8.7 km below the surface
- Felt
- no reports yet
- Nearest
- Alameda County, 16 km SSE
- Nearest mapped fault
- Calaveras fault, 2 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 3 days ago
Earthquake alerts for San Ramon, CA
Get a notification in this browser when USGS records an earthquake near San Ramon, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 9 km (6 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
Likely felt in: San Ramon in town, intensity II · Danville 5 km, intensity II · Diablo 7 km, intensity II · Blackhawk 8 km, intensity II · Dublin 9 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 11 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 1,400,000× the energy of this one
- Magna, Utah 2020 M 5.7 970,000× the energy of this one
- Around the size people start to feel M 3.0 86× the energy of this one
- This earthquake M 1.7 about 11 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 4.5 on 2019-10-15 — about 13,000 times the energy of this one.
Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:
- 7.9 The 1906 San Francisco, California Earthquake · 50 km W of this epicentre
- 5.8 The 1980 Livermore, California Earthquake · 20 km ENE of this epicentre
- 5.7 15 km NE of East Foothills, California · 42 km SE of this epicentre
- 5.5 6 km NNE of East Foothills, California · 42 km SSE of this epicentre
- 5.4 9 km NE of Livermore, California · 25 km E 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 37.7752, -121.9830. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Alameda County, CA | 16 km (10 mi) | SSE | earthquakes near Alameda County |
| Contra Costa County, CA | 16 km (10 mi) | N | earthquakes near Contra Costa County |
| San Mateo County, CA | 53 km (33 mi) | SW | earthquakes near San Mateo County |
| Solano County, CA | 55 km (34 mi) | N | earthquakes near Solano County |
| San Joaquin County, CA | 65 km (40 mi) | ENE | earthquakes near San Joaquin County |
| Santa Clara County, CA | 67 km (41 mi) | SSE | earthquakes near Santa Clara County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
3 earthquakes have been recorded within 50 km since this one.
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.