QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Cayucos, CA

No earthquake was likely felt in Cayucos in the 24 hours to 6:54 am PST (14:54 UTC). The last one was M 2.1, 15 km (9 mi) E, at 6:08 am PDT on 21 October 2026, estimated intensity II (weak) in town; 3 felt reports to USGS. Every earthquake near Cayucos

This page: a magnitude 1.8 earthquake was recorded 10 km (6 mi) northeast of Cayucos, CA, at 11:02 pm PST on 10 January 2021 (07:02 UTC), 5.9 km deep.

USGS: 10km NE of Cayucos, CA

72 km (45 mi) NNW of Santa Maria, CA

11:02 pm PST, Jan 10, 2021 · · 5.9 km deep · released about 14 lb of TNT

10 km30 km60 km120 km N San Luis Obispo County 36 kmMonterey County 93 kmKings County 110 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:02 pm PST on 10 January 2021 ()
Where
10 km (6 mi) northeast of Cayucos, CA · earthquakes near Cayucos
Magnitude
M 1.8 (md)
Depth
5.9 km below the surface
Felt
no reports yet
Nearest
San Luis Obispo County, 36 km ESE
Nearest mapped fault
Los Osos fault, 20 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 2124 days ago

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 12 km (7 mi) from the epicentre. In Cayucos, 10 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: Cayucos 10 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 4 earthquakes of M5 or more within 50 km:

  1. 6.5 10 km NE of San Simeon, California · 33 km NW of this epicentre
  2. 5.8 1934 Parkfield, California Earthquake · 40 km NNE of this epicentre
  3. 5.7 Southwest of Cambria, California · 35 km W of this epicentre
  4. 5.1 13km N of San Miguel, CA · 41 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 35.5102, -120.8125. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Luis Obispo County, CA 36 km (22 mi) ESE earthquakes near San Luis Obispo County
Monterey County, CA 93 km (58 mi) NNW earthquakes near Monterey County
Kings County, CA 110 km (68 mi) NE earthquakes near Kings County
Santa Barbara County, CA 129 km (80 mi) SSE earthquakes near Santa Barbara County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

40 earthquakes have been recorded within 50 km since this one.

  1. 1.9 17km NNE of San Simeon, CA
  2. 1.6 7km E of Atascadero, CA
  3. 1.6 10km NNE of San Simeon, CA
  4. 1.7 8km SW of Atascadero, CA
  5. 1.6 11km WSW of Templeton, CA
  6. 2.3 13km NNE of Cambria, CA
  7. 2.3 11km WSW of Morro Bay, CA
  8. 1.7 11km WSW of Templeton, CA
  9. 2.0 17km N of San Simeon, CA
  10. 1.8 13km N of San Simeon, CA
  11. 1.5 6km NNE of Santa Margarita, CA
  12. 1.8 2km ENE of Cayucos, CA
  13. 2.8 9km WNW of Templeton, CA
  14. 1.9 7km WNW of Paso Robles, CA
  15. 2.4 11km SSW of Lake Nacimiento, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.