Earthquake · reviewed by a seismologist
M 3.2ml
Earthquake near Paso Robles, CA
No earthquake was likely felt in Paso Robles in the 24 hours to 5:22 am PST (13:22 UTC). The last one was M 2.5, 21 km (13 mi) S, at 11:41 pm PDT on 15 August 2026, estimated intensity II (weak) in town; 61 felt reports to USGS. Every earthquake near Paso Robles
This page: a magnitude 3.2 earthquake was recorded 37 km (23 mi) east-northeast of Paso Robles, CA, at 12:41 pm PDT on 28 September 2021 (19:41 UTC), 3.8 km deep. 4 people have reported feeling it to USGS.
USGS: 4km NNW of Cholame, CA
- When
- 12:41 pm PDT on 28 September 2021 ()
- Where
- 37 km (23 mi) east-northeast of Paso Robles, CA · earthquakes near Paso Robles
- Magnitude
- M 3.2 (ml)
- Depth
- 3.8 km below the surface
- Felt
- 4 reports · strongest reported intensity III
- Nearest
- San Luis Obispo County, 43 km SSW
- Nearest mapped fault
- San Andreas 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 1804 days ago
Earthquake alerts for Paso Robles, CA
Get a notification in this browser when USGS records an earthquake near Paso Robles, 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 49 km (30 mi) from the epicentre. In Paso Robles, 37 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: Avenal 32 km, intensity II · Paso Robles 37 km, intensity II · Kettleman City 42 km, intensity II · Coalinga 43 km, intensity II · Atascadero 44 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 1.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 150,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 6,900× the energy of this one
- Magna, Utah 2020 M 5.7 4,900× the energy of this one
- This earthquake M 3.2 about 1.1 tons of TNT
- Around the size people start to feel M 3.0 this one released 2.3× 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 since 2016 was M 4.3 on 2019-12-17 — about 38 times the energy of this one.
Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:
- 6.5 1922 Parkfield, California Earthquake · 6 km E of this epicentre
- 6.4 1901 Parkfield, California Earthquake · 32 km NNW of this epicentre
- 6.0 2004 Parkfield, California Earthquake · 8 km NW of this epicentre
- 5.8 1934 Parkfield, California Earthquake · 34 km WNW of this epicentre
- 5.6 8 km SW of Huron, California · 45 km NNE 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 35.7593, -120.3100. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| San Luis Obispo County, CA | 43 km (27 mi) | SSW | earthquakes near San Luis Obispo County |
| Kings County, CA | 57 km (35 mi) | NE | earthquakes near Kings County |
| Monterey County, CA | 105 km (65 mi) | WNW | earthquakes near Monterey County |
| San Benito County, CA | 118 km (73 mi) | NW | earthquakes near San Benito County |
| Fresno County, CA | 126 km (78 mi) | NNE | earthquakes near Fresno County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
46 earthquakes have been recorded within 50 km since this one.
- 1.7 8km SSE of Kettleman City, CA
- 1.5 6km E of Atascadero, CA
- 1.9 3km SW of Huron, CA
- 2.8 8km NNW of Cholame, CA
- 3.0 7km NNW of Cholame, CA
- 1.5 13km SW of Huron, CA
- 1.8 6km NNE of Avenal, CA
- 2.6 10km NNE of Avenal, CA
- 1.5 34km S of Kettleman City, CA
- 1.9 33km NNE of Simmler, CA
- 1.6 18km NW of Parkfield, CA
- 1.8 11km ENE of Coalinga, CA
- 2.3 10km ENE of Coalinga, CA
- 2.0 11km NW of Parkfield, CA
- 1.8 22km SE of Kettleman City, 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.