QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

Earthquake near Signal Hill, CA

No earthquake was likely felt in Signal Hill in the 24 hours to 1:29 am PST (09:29 UTC). The last one was M 3.2, 2 km (2 mi) SW, at 12:44 am PDT on 9 October 2026, estimated intensity III (weak) in town; 1,090 felt reports to USGS. Every earthquake near Signal Hill

This page: a magnitude 2.6 earthquake was recorded 3 km (2 mi) south-southwest of Signal Hill, CA, at 3:42 am PDT on 5 August 2018 (10:42 UTC), 12 km deep. 877 people have reported feeling it to USGS.

USGS: 3km SSW of Signal Hill, CA

in Long Beach, CA · 34 km (21 mi) SE of Los Angeles, CA

3:42 am PDT, Aug 5, 2018 · · 12 km deep · released about 220 lb of TNT

Every earthquake near Signal Hill Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 39 kmLos Angeles County 47 kmVentura County 109 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
3:42 am PDT on 5 August 2018 ()
Where
3 km (2 mi) south-southwest of Signal Hill, CA · earthquakes near Signal Hill
Magnitude
M 2.6 (ml)
Depth
12 km below the surface
Felt
877 reports · strongest reported intensity IV
Nearest
Orange County, 39 km ESE
Nearest mapped fault
Palos Verdes fault, 9 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 2997 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 20 km (12 mi) from the epicentre. In Signal Hill, 3 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: Long Beach in town, intensity II · Signal Hill 3 km, intensity II · Seal Beach 8 km, intensity II · Lakewood 9 km, intensity II · Carson 11 km, intensity II · Paramount 13 km, intensity II · Bellflower 13 km, intensity II · Compton 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 68,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 48,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.3× the energy of this one
  4. This earthquake M 2.6 about 220 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 23 km SE of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 33 km NNE of this epicentre
  3. 5.4 5km S of Chino Hills, CA · 43 km ENE of this epicentre
  4. 5.3 2 km SSW of Santa Monica, California · 39 km NW of this epicentre
  5. 5.3 7km W of Newport Beach, CA · 24 km SE 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 33.7778, -118.1800. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 39 km (24 mi) ESE earthquakes near Orange County
Los Angeles County, CA 47 km (29 mi) N earthquakes near Los Angeles County
Ventura County, CA 109 km (68 mi) NW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 2.1 1km E of Santa Monica, CA
  2. 1.9 9km SW of Newport Beach, CA
  3. 1.9 10km SW of Newport Beach, CA
  4. 2.1 9km SW of Newport Beach, CA
  5. 1.7 3km N of View Park-Windsor Hills, CA
  6. 1.6 2km WSW of Santa Monica, CA
  7. 1.5 3km WSW of Willowbrook, CA
  8. 2.3 3km W of San Pedro, CA
  9. 1.6 1km ESE of Maywood, CA
  10. 1.7 1km SSW of Gardena, CA
  11. 2.1 8km W of Newport Beach, CA
  12. 2.4 7km W of Newport Beach, CA
  13. 2.1 9km ENE of North Tustin, CA
  14. 1.8 8km E of Yorba Linda, CA
  15. 2.0 1km NW of Hawthorne, 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.