Earthquake · reviewed by a seismologist
M 2.8md
Earthquake near Mountain House, CA
No earthquake was likely felt in Mountain House in the 24 hours to 8:37 pm PST (04:37 UTC). The last one was M 3.5, 41 km (26 mi) S, at 7:21 am PDT on 27 September 2026, estimated intensity II (weak) in town; 8 felt reports to USGS. Every earthquake near Mountain House
This page: a magnitude 2.8 earthquake was recorded 6 km (4 mi) west-northwest of Mountain House, CA, at 5:58 pm PST on 7 November 2018 (01:58 UTC), 16 km deep. 14 people have reported feeling it to USGS.
USGS: 6km WNW of Mountain House, CA
58 km (36 mi) NNE of San Jose, CA · 16 km (10 mi) WNW of Tracy, CA
- When
- 5:58 pm PST on 7 November 2018 ()
- Where
- 6 km (4 mi) west-northwest of Mountain House, CA · earthquakes near Mountain House
- Magnitude
- M 2.8 (md)
- Depth
- 16 km below the surface
- Felt
- 14 reports · strongest reported intensity II
- Nearest
- Alameda County, 31 km WSW
- Nearest mapped fault
- Corral Hollow-Carnegie fault, 12 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 2923 days ago
Earthquake alerts for Mountain House, CA
Get a notification in this browser when USGS records an earthquake near Mountain House, 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 21 km (13 mi) from the epicentre. In Mountain House, 6 km away, the estimate is intensity II (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: Discovery Bay 13 km, intensity II · Brentwood 17 km, intensity II · Tracy 17 km, intensity II · Livermore 19 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 450 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 34,000× the energy of this one
- Magna, Utah 2020 M 5.7 24,000× the energy of this one
- Around the size people start to feel M 3.0 2.1× the energy of this one
- This earthquake M 2.8 about 450 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
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:
- 5.8 The 1980 Livermore, California Earthquake · 15 km WNW of this epicentre
- 5.7 15 km NE of East Foothills, California · 36 km S of this epicentre
- 5.5 6 km NNE of East Foothills, California · 43 km SSW of this epicentre
- 5.4 9 km NE of Livermore, California · 10 km WSW of this epicentre
- 5.3 6 km E of East Foothills, California · 46 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 37.7952, -121.6117. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Alameda County, CA | 31 km (19 mi) | WSW | earthquakes near Alameda County |
| Contra Costa County, CA | 33 km (20 mi) | WNW | earthquakes near Contra Costa County |
| San Joaquin County, CA | 34 km (21 mi) | ENE | earthquakes near San Joaquin County |
| Stanislaus County, CA | 60 km (37 mi) | ESE | earthquakes near Stanislaus County |
| Solano County, CA | 60 km (37 mi) | NNW | earthquakes near Solano County |
| Santa Clara County, CA | 64 km (40 mi) | S | earthquakes near Santa Clara County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
57 earthquakes have been recorded within 50 km since this one.
- 1.6 14km SSE of Livermore, CA
- 2.1 9km NNE of Alum Rock, CA
- 1.5 9km NNE of Alum Rock, CA
- 1.8 2km NE of San Leandro, CA
- 2.3 2km SSE of Concord, CA
- 2.0 3km E of Union City, CA
- 1.7 5km WNW of Sunol, CA
- 1.7 3km WNW of Diablo, CA
- 2.3 8km E of Alum Rock, CA
- 1.7 11km SE of Livermore, CA
- 1.6 5km SW of Pacheco, CA
- 2.7 3km NNE of San Ramon, CA
- 2.4 1km N of Vine Hill, CA
- 2.4 17km ESE of Livermore, CA
- 2.0 1km NNE of Pacheco, 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.