QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

2km NNE of Morro Bay, CA

· 2.6 km deep · released about 40 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Luis Obispo County 36 kmMonterey County 105 kmSanta Barbara County 119 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
Magnitude
M 2.1 (md)
Depth
2.6 km below the surface
Felt
4 reports · strongest reported intensity IV
Nearest
San Luis Obispo County, 36 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2315 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 4 people have reported feeling it to USGS.

How big was it?

This earthquake released about 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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.

Where

Epicentre 35.3787, -120.8423. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Luis Obispo County, CA 36 km (22 mi) W of here earthquakes near San Luis Obispo County
Monterey County, CA 105 km (65 mi) SSE of here earthquakes near Monterey County
Santa Barbara County, CA 119 km (74 mi) NW of here earthquakes near Santa Barbara County
Kings County, CA 121 km (75 mi) SW of here earthquakes near Kings 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. 1.6 13km W of Lake Nacimiento, CA
  2. 1.8 10km NE of Cayucos, CA
  3. 2.7 13km NE of San Simeon, CA
  4. 1.7 9km W of Templeton, CA
  5. 1.7 8km NNE of Cayucos, CA
  6. 1.6 8km NNE of Cayucos, CA
  7. 1.8 6km E of Atascadero, CA
  8. 2.5 15km W of Lake Nacimiento, CA
  9. 2.5 8km NNE of Cayucos, CA
  10. 2.6 8km NNE of Cayucos, CA
  11. 2.4 24km SE of Santa Margarita, CA
  12. 1.9 6km NE of San Luis Obispo, CA
  13. 2.5 8km W of Templeton, CA
  14. 1.8 6km W of Santa Margarita, CA
  15. 2.6 11km NNE 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

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