QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Buellton, CA

No earthquake was likely felt in Buellton in the 24 hours to 5:59 am PST (13:59 UTC). The last one was M 2.2, 17 km (10 mi) N, at 8:51 am PDT on 23 July 2026, estimated intensity II (weak) in town. Every earthquake near Buellton

This page: a magnitude 1.7 earthquake was recorded 4 km (2 mi) south of Buellton, CA, at 10:21 pm PDT on 16 July 2018 (05:21 UTC), less than 1 km deep. 15 people have reported feeling it to USGS.

USGS: 4km S of Buellton, CA

45 km (28 mi) SSE of Santa Maria, CA · 136 km (85 mi) SW of Bakersfield, CA

10:21 pm PDT, Jul 16, 2018 · · -0.1 km deep · released about 10 lb of TNT

Every earthquake near Buellton Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Barbara County 15 kmSan Luis Obispo County 93 kmVentura County 101 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
10:21 pm PDT on 16 July 2018 ()
Where
4 km (2 mi) south of Buellton, CA · earthquakes near Buellton
Magnitude
M 1.7 (ml)
Depth
-0.1 km below the surface
Felt
15 reports · strongest reported intensity IV
Nearest
Santa Barbara County, 15 km ESE
Nearest mapped fault
Santa Ynez fault, 5 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 3030 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 Buellton, 4 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: Santa Ynez 11 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 95× the energy of this one
  4. This earthquake M 1.7 about 10 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 4.3 on 2017-10-26 — about 9,400 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 · 48 km WNW of this epicentre
  2. 6.8 The 1925 Santa Barbara, California Earthquake · 48 km SE of this epicentre
  3. 5.8 Near Los Alamos, California · 31 km NW of this epicentre
  4. 5.8 Near Los Alamos, California · 17 km NW of this epicentre
  5. 5.7 Near Los Alamos, California · 2 km N 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 34.5778, -120.1973. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Barbara County, CA 15 km (9 mi) ESE earthquakes near Santa Barbara County
San Luis Obispo County, CA 93 km (58 mi) NNW earthquakes near San Luis Obispo County
Ventura County, CA 101 km (62 mi) ESE earthquakes near Ventura County

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

Aftershocks so far

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

  1. 1.7 19km SSW of Lompoc, CA
  2. 2.3 32km NNE of Goleta, CA
  3. 1.8 12km NNE of Los Olivos, CA
  4. 2.6 12km SSW of Lompoc, CA
  5. 2.1 13km SSW of Lompoc, CA
  6. 1.6 13km NNE of Los Alamos, CA
  7. 1.8 12km NNE of Goleta, CA
  8. 2.0 13km SSW of Lompoc, CA
  9. 2.0 8km ESE of Santa Ynez, CA
  10. 1.8 9km NNW of Santa Barbara, CA
  11. 1.5 11km NNW of Montecito, CA
  12. 1.7 14km NE of Los Olivos, CA
  13. 2.0 31 km SW of Lompoc, CA
  14. 2.6 13km SSW of Lompoc, CA
  15. 2.1 5km SSW of Orcutt, 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.