Earthquake · reviewed by a seismologist
M 2.9ml
Earthquake near Castro Valley, CA
No earthquake was likely felt in Castro Valley in the 24 hours to 2:44 am PST (10:44 UTC). The last one was M 1.9, 10 km (6 mi) ESE, at 10:32 am PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Castro Valley
This page: a magnitude 2.9 earthquake was recorded 2 km (1 mi) northwest of Castro Valley, CA, at 11:52 am PDT on 15 July 2018 (18:52 UTC), 5.3 km deep. 229 people have reported feeling it to USGS.
USGS: 2km NW of Castro Valley, CA
13 km (8 mi) ESE of Oakland, CA · 5 km (3 mi) E of San Leandro, CA
- When
- 11:52 am PDT on 15 July 2018 ()
- Where
- 2 km (1 mi) northwest of Castro Valley, CA · earthquakes near Castro Valley
- Magnitude
- M 2.9 (ml)
- Depth
- 5.3 km below the surface
- Felt
- 229 reports · strongest reported intensity IV
- Nearest
- Alameda County, 18 km ESE
- Nearest mapped fault
- Hayward fault, under 1 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2508 days ago
Earthquake alerts for Castro Valley, CA
Get a notification in this browser when USGS records an earthquake near Castro Valley, 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 small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 29 km (18 mi) from the epicentre. In Castro Valley, 2 km away, the estimate is intensity III (weak). 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: Castro Valley 2 km, intensity III · San Lorenzo 4 km, intensity III · Hayward 5 km, intensity III · San Leandro 5 km, intensity III · San Ramon 14 km, intensity III · Union City 14 km, intensity III · Dublin 15 km, intensity III · Alameda 16 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 570 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 27,000× the energy of this one
- Magna, Utah 2020 M 5.7 19,000× the energy of this one
- Around the size people start to feel M 3.0 1.7× the energy of this one
- This earthquake M 2.9 about 570 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 4.4 on 2018-01-04 — about 200 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 · 40 km W of this epicentre
- 5.8 The 1980 Livermore, California Earthquake · 33 km ENE of this epicentre
- 5.7 15 km NE of East Foothills, California · 45 km SE of this epicentre
- 5.5 6 km NNE of East Foothills, California · 42 km SE of this epicentre
- 5.4 9 km NE of Livermore, California · 35 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 37.7067, -122.1035. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Alameda County, CA | 18 km (11 mi) | ESE | earthquakes near Alameda County |
| Contra Costa County, CA | 27 km (17 mi) | NNE | earthquakes near Contra Costa County |
| San Mateo County, CA | 40 km (25 mi) | SW | earthquakes near San Mateo County |
| Solano County, CA | 64 km (40 mi) | NNE | earthquakes near Solano County |
| Santa Clara County, CA | 65 km (40 mi) | SE | earthquakes near Santa Clara County |
| Marin County, CA | 68 km (42 mi) | NW | earthquakes near Marin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
54 earthquakes have been recorded within 50 km since this one.
- 1.8 6km ESE of San Ramon, CA
- 1.9 18km SSE of Livermore, CA
- 1.6 6km ESE of San Ramon, CA
- 1.6 9km WSW of Brentwood, CA
- 2.0 4km SW of Colma, CA
- 1.6 4km WSW of Daly City, CA
- 1.9 2km N of San Leandro, CA
- 1.8 2km E of San Leandro, CA
- 1.8 5km S of Alameda, CA
- 1.8 11km ESE of Sunol, CA
- 1.9 8km SE of Livermore, CA
- 2.0 4km ESE of Union City, CA
- 2.7 7km NNE of Bay Point, CA
- 1.7 8km NNE of Milpitas, CA
- 1.7 17km SE of Livermore, 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.