QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

Earthquake near Los Olivos, CA

No earthquake was likely felt in Los Olivos in the 24 hours to 10:17 am PST (18:17 UTC). The last one was M 2.2, 14 km (8 mi) NW, at 8:51 am PDT on 23 July 2026, estimated intensity II (weak) in town. Every earthquake near Los Olivos

This page: a magnitude 2.9 earthquake was recorded 9 km (5 mi) northwest of Los Olivos, CA, at 5:37 pm PDT on 21 September 2017 (00:37 UTC), 1.7 km deep. 13 people have reported feeling it to USGS.

USGS: 9km NW of Los Olivos, CA

33 km (21 mi) SE of Santa Maria, CA · 124 km (77 mi) WSW of Bakersfield, CA

5:37 pm PDT, Sep 21, 2017 · · 1.7 km deep · released about 590 lb of TNT

Every earthquake near Los Olivos Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Barbara County 25 kmSan Luis Obispo County 77 kmVentura County 104 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
5:37 pm PDT on 21 September 2017 ()
Where
9 km (5 mi) northwest of Los Olivos, CA · earthquakes near Los Olivos
Magnitude
M 2.9 (ml)
Depth
1.7 km below the surface
Felt
13 reports · strongest reported intensity III
Nearest
Santa Barbara County, 25 km SSE
Nearest mapped fault
Los Alamos 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 3304 days ago

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 30 km (19 mi) from the epicentre. In Los Olivos, 9 km away, the estimate is intensity III (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: Los Alamos 10 km, intensity III · Santa Ynez 15 km, intensity III · Lompoc 28 km, intensity II · Orcutt 28 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 590 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 26,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 18,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.6× the energy of this one
  4. This earthquake M 2.9 about 590 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 4.1 on 2017-05-17 — about 63 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.9 The 1927 Lompoc, California Earthquake · 49 km W of this epicentre
  2. 5.8 Near Los Alamos, California · 22 km WNW of this epicentre
  3. 5.8 Near Los Alamos, California · 12 km WSW of this epicentre
  4. 5.7 Near Los Alamos, California · 15 km S of this epicentre
  5. 5.0 5 km SSW of Nipomo, California · 42 km NW 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 34.7307, -120.1718. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Barbara County, CA 25 km (15 mi) SSE earthquakes near Santa Barbara County
San Luis Obispo County, CA 77 km (48 mi) NNW earthquakes near San Luis Obispo County
Ventura County, CA 104 km (64 mi) ESE earthquakes near Ventura County

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

Aftershocks so far

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

  1. 2.2 4km ESE of Orcutt, CA
  2. 1.9 17km W of Vandenberg Air Force Base, CA
  3. 2.4 4km ESE of Orcutt, CA
  4. 3.2 4km ESE of Orcutt, CA
  5. 1.5 4km ESE of Orcutt, CA
  6. 1.7 12km NE of Goleta, CA
  7. 2.1 30km S of Solvang, CA
  8. 2.2 12km S of Guadalupe, CA
  9. 2.7 8km SSW of Los Alamos, CA
  10. 1.8 9km W of Isla Vista, CA
  11. 1.8 10km SE of Santa Ynez, CA
  12. 1.7 8km ESE of Vandenberg Village, CA
  13. 1.7 4km S of Buellton, CA
  14. 1.8 12km NNW of Santa Barbara, CA
  15. 2.0 13km W of Isla Vista, 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.