QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

Earthquake near Santa Barbara, CA

No earthquake was likely felt in Santa Barbara in the 24 hours to 5:51 pm PST (01:51 UTC). The last one was M 2.1, 15 km (9 mi) S, at 9:33 pm PST on 4 November 2026, estimated intensity II (weak) in town. Every earthquake near Santa Barbara

This page: a magnitude 2.4 earthquake was recorded 24 km (15 mi) south of Santa Barbara, CA, at 3:18 pm PDT on 27 July 2021 (22:18 UTC), 6.0 km deep.

USGS: 24km NW of Santa Cruz Is. (E end), CA

22 km (14 mi) SSE of Santa Barbara, CA · 117 km (73 mi) W of Los Angeles, CA

3:18 pm PDT, Jul 27, 2021 · · 6.0 km deep · released about 120 lb of TNT

10 km30 km60 km120 km N Santa Barbara County 50 kmVentura County 52 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
3:18 pm PDT on 27 July 2021 ()
Where
24 km (15 mi) south of Santa Barbara, CA · earthquakes near Santa Barbara
Magnitude
M 2.4 (ml)
Depth
6.0 km below the surface
Felt
no reports yet
Nearest
Santa Barbara County, 50 km NW
Nearest mapped fault
Mid-Channel fault, 1 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 1933 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 20 km (12 mi) from the epicentre. In Santa Barbara, 24 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: Summerland, Carpinteria, Toro Canyon, Montecito, Mission Canyon, Isla Vista.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 92,000× the energy of this one
  3. Around the size people start to feel M 3.0 8.2× the energy of this one
  4. This earthquake M 2.4 about 120 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

The largest earthquake within 50 km since 2016 was M 5.3 on 2018-04-05 — about 22,000 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 The 1925 Santa Barbara, California Earthquake · 16 km NW of this epicentre
  2. 5.5 30 km SW of Channel Islands Beach, California · 28 km SSE of this epicentre
  3. 5.5 10 km NE of Toro Canyon, California · 36 km NNE of this epicentre
  4. 5.5 The 1941 Santa Barbara, California Earthquake · 16 km NE of this epicentre
  5. 5.2 9 km SW of Channel Islands Beach, California · 36 km ESE 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 34.2073, -119.6643. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Barbara County, CA 50 km (31 mi) NW earthquakes near Santa Barbara County
Ventura County, CA 52 km (32 mi) ENE earthquakes near Ventura 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. 2.4 1km NW of Goleta, CA
  2. 1.6 6km W of Ojai, CA
  3. 1.9 1km WSW of Goleta, CA
  4. 1.8 18km SSW of Santa Barbara, CA
  5. 1.9 18km SSW of Santa Cruz Is. (E end), CA
  6. 1.5 20km NNE of Carpinteria, CA
  7. 1.9 4km WSW of Ojai, CA
  8. 3.2 5km WSW of Ojai, CA
  9. 1.8 20km NNW of Santa Cruz Is. (E end), CA
  10. 2.2 21km SSW of Carpinteria, CA
  11. 1.9 21km NNW of Santa Cruz Is. (E end), CA
  12. 3.5 11km SE of Carpinteria, CA
  13. 2.2 11km SE of Carpinteria, CA
  14. 1.7 14km WSW of Isla Vista, CA
  15. 2.0 17km SSW of Santa Barbara, 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.