Earthquake · reviewed by a seismologist
M 4.7mw
Earthquake near Cambria, CA
No earthquake was likely felt in Cambria in the 24 hours to 8:40 am PST (16:40 UTC). The last one was M 2.3, 18 km (11 mi) NNE, at 5:04 pm PDT on 21 September 2026, estimated intensity II (weak) in town. Every earthquake near Cambria
This page: a magnitude 4.7 earthquake was recorded 31 km (19 mi) northwest of Cambria, CA, at 4:42 pm PDT on 25 October 2021 (23:42 UTC), 7.8 km deep. 619 people have reported feeling it to USGS.
USGS: 18km NW of San Simeon, CA
- When
- 4:42 pm PDT on 25 October 2021 ()
- Where
- 31 km (19 mi) northwest of Cambria, CA · earthquakes near Cambria
- Magnitude
- M 4.7 (mw)
- Depth
- 7.8 km below the surface
- Felt
- 619 reports · strongest reported intensity IV
- Measured shaking
- intensity V (ShakeMap)
- USGS impact alert
- green
- Tsunami
- USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
- Nearest
- Monterey County, 52 km N
- Nearest mapped fault
- San Gregorio fault, 2 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 1769 days ago
Earthquake alerts for Cambria, CA
Get a notification in this browser when USGS records an earthquake near Cambria, 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 light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.
At this magnitude and depth, people at rest would likely notice it out to about 154 km (96 mi) from the epicentre. In Cambria, 31 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: Cambria 31 km, intensity III. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 140 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.7 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 1,200× the energy of this one
- Mineral, Virginia 2011 M 5.8 53× the energy of this one
- Magna, Utah 2020 M 5.7 38× the energy of this one
- This earthquake M 4.7 about 140 tons of TNT
- Around the size people start to feel M 3.0 this one released 300× more
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 (31 mi) since our catalogue begins in 2016. No other earthquake of M4 or more has been recorded this close in that time.
Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:
- 6.5 10 km NE of San Simeon, California · 20 km ESE of this epicentre
- 6.2 28km NW of Cambria, CA · 6 km SSW of this epicentre
- 5.7 Southwest of Cambria, California · 32 km SSE of this epicentre
- 5.2 26km NNW of Lake Nacimiento, CA · 36 km ENE of this epicentre
- 5.2 25 km NW of San Simeon, California · 8 km NW 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 35.7758, -121.3043. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Monterey County, CA | 52 km (32 mi) | N | earthquakes near Monterey County |
| San Luis Obispo County, CA | 89 km (55 mi) | ESE | earthquakes near San Luis Obispo County |
| San Benito County, CA | 95 km (59 mi) | NNE | earthquakes near San Benito County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
51 earthquakes have been recorded within 50 km since this one.
- 2.2 8km NE of San Simeon, CA
- 2.1 8km NE of San Simeon, CA
- 2.5 8km NE of San Simeon, CA
- 1.9 26km W of San Simeon, CA
- 3.3 8km NE of San Simeon, CA
- 2.0 8km NNE of San Simeon, CA
- 2.9 8km NNE of San Simeon, CA
- 2.3 11km NNE of Cayucos, CA
- 1.8 22km NW of San Simeon, CA
- 1.5 12km NNE of Cayucos, CA
- 2.5 12km NNE of Cayucos, CA
- 2.0 6km NW of San Simeon, CA
- 2.2 12km NNE of Cayucos, CA
- 1.6 19km NW of San Simeon, CA
- 2.5 13km NNW of San Simeon, 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.