QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Port Hueneme, CA

No earthquake was likely felt in Port Hueneme in the 24 hours to 12:51 am PST (08:51 UTC). The last one was M 3.8, 48 km (30 mi) NE, at 8:00 pm PDT on 29 September 2026, estimated intensity II (weak) in town; 199 felt reports to USGS. Every earthquake near Port Hueneme

This page: a magnitude 2.3 earthquake was recorded 5 km (3 mi) southwest of Port Hueneme, CA, at 3:02 pm PDT on 29 September 2017 (22:02 UTC), 22 km deep. 4 people have reported feeling it to USGS.

USGS: 5km SW of Port Hueneme, CA

9 km (6 mi) SSW of Oxnard, CA · 77 km (48 mi) W of Los Angeles, CA

3:02 pm PDT, Sep 29, 2017 · · 22 km deep · released about 74 lb of TNT

Every earthquake near Port Hueneme Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Ventura County 28 kmSanta Barbara County 87 kmLos Angeles County 90 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
3:02 pm PDT on 29 September 2017 ()
Where
5 km (3 mi) southwest of Port Hueneme, CA · earthquakes near Port Hueneme
Magnitude
M 2.3 (ml)
Depth
22 km below the surface
Felt
4 reports · strongest reported intensity II
Nearest
Ventura County, 28 km NNE
Nearest mapped fault
Malibu Coast fault, 13 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 1558 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Port Hueneme, 5 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: Channel Islands Beach, Oxnard, El Rio, Ventura, Saticoy, Camarillo.

How big was it?

This earthquake released about 74 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 140,000× the energy of this one
  3. Around the size people start to feel M 3.0 13× the energy of this one
  4. This earthquake M 2.3 about 74 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 2016-03-12 — about 640 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. 5.5 30 km SW of Channel Islands Beach, California · 28 km WSW of this epicentre
  2. 5.5 10 km NE of Toro Canyon, California · 49 km NNW of this epicentre
  3. 5.5 The 1941 Santa Barbara, California Earthquake · 38 km NW of this epicentre
  4. 5.3 The 1973 Point Mugu, California Earthquake · 23 km SE of this epicentre
  5. 5.2 9 km SW of Channel Islands Beach, California · 6 km WSW 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 34.1175, -119.2355. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Ventura County, CA 28 km (18 mi) NNE earthquakes near Ventura County
Santa Barbara County, CA 87 km (54 mi) WNW earthquakes near Santa Barbara County
Los Angeles County, CA 90 km (56 mi) E earthquakes near Los Angeles County

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

Aftershocks so far

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

  1. 2.4 16km SW of Malibu, CA
  2. 2.3 21km NNW of Santa Cruz Is. (E end), CA
  3. 2.0 14km SW of Port Hueneme, CA
  4. 1.7 6km ESE of Port Hueneme, CA
  5. 1.7 7km NNW of Fillmore, CA
  6. 2.4 17km SW of Port Hueneme, CA
  7. 1.8 3 km NE of Malibu, California
  8. 1.9 20km SE of Port Hueneme, CA
  9. 2.4 15km WNW of Malibu, CA
  10. 2.8 16km N of Santa Paula, CA
  11. 1.5 15km N of Santa Paula, CA
  12. 2.2 16km N of Santa Paula, CA
  13. 1.7 15km N of Santa Paula, CA
  14. 1.8 15km N of Santa Paula, CA
  15. 1.6 15km N of Santa Paula, 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.