Earthquake · reviewed by a seismologist
M 2.3md
Earthquake near Paso Robles, CA
No earthquake was likely felt in Paso Robles in the 24 hours to 11:49 am PST (19:49 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 2.3 earthquake was recorded 40 km (25 mi) west-northwest of Paso Robles, CA, at 2:27 pm PDT on 20 September 2018 (21:27 UTC), 5.9 km deep. 2 people have reported feeling it to USGS.
USGS: 17km NNE of San Simeon, CA
- When
- 2:27 pm PDT on 20 September 2018 ()
- Where
- 40 km (25 mi) west-northwest of Paso Robles, CA · earthquakes near Paso Robles
- Magnitude
- M 2.3 (md)
- Depth
- 5.9 km below the surface
- Felt
- 2 reports · strongest reported intensity IV
- Nearest
- Monterey County, 55 km NNW
- Nearest mapped fault
- San Simeon fault, 16 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 1557 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 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 18 km (11 mi) from the epicentre. In Paso Robles, 40 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.
Earthquakes near other towns within 30 km: Lake Nacimiento, Cambria.
How big was it?
This earthquake released about 77 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 200,000× the energy of this one
- Magna, Utah 2020 M 5.7 140,000× the energy of this one
- Around the size people start to feel M 3.0 12× the energy of this one
- This earthquake M 2.3 about 77 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 9 earthquakes of M5 or more within 50 km; the five largest:
- 6.5 10 km NE of San Simeon, California · 9 km S of this epicentre
- 6.2 28km NW of Cambria, CA · 22 km WSW of this epicentre
- 5.8 1934 Parkfield, California Earthquake · 39 km E of this epicentre
- 5.7 Southwest of Cambria, California · 33 km SSW of this epicentre
- 5.2 26km NNW of Lake Nacimiento, CA · 22 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 35.7788, -121.0920. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Monterey County, CA | 55 km (34 mi) | NNW | earthquakes near Monterey County |
| San Luis Obispo County, CA | 73 km (45 mi) | SE | earthquakes near San Luis Obispo County |
| San Benito County, CA | 93 km (58 mi) | N | earthquakes near San Benito County |
| Kings County, CA | 119 km (74 mi) | ENE | earthquakes near Kings County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
34 earthquakes have been recorded within 50 km since this one.
- 1.6 12km NNE of Cayucos, CA
- 2.2 22km SE of Lopez Point, CA
- 2.7 8km ENE of San Simeon, CA
- 1.8 24km NNW of San Simeon, CA
- 1.5 3km SSE of San Ardo, CA
- 1.5 5km NNE of San Ardo, CA
- 1.6 4km WSW of San Ardo, CA
- 2.2 8km ENE of San Simeon, CA
- 1.5 8km WNW of Templeton, CA
- 2.0 13km WSW of Lake Nacimiento, CA
- 2.0 11km WSW of Templeton, CA
- 1.9 11km NNE of San Simeon, CA
- 2.7 22km SSW of San Simeon, CA
- 1.5 15km W of Lake Nacimiento, CA
- 1.8 18km W 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.