QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Signal Hill, CA

No earthquake was likely felt in Signal Hill in the 24 hours to 2:45 am PST (10:45 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 1.5 earthquake was recorded 3 km (2 mi) south-southwest of Signal Hill, CA, at 5:30 pm PDT on 24 August 2016 (00:30 UTC), 12 km deep.

USGS: 3km SSW of Signal Hill, CA

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

5:30 pm PDT, Aug 24, 2016 · · 12 km deep · released about 5.4 lb of TNT

10 km30 km60 km120 km N Orange County 40 kmLos Angeles County 47 kmVentura County 108 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
5:30 pm PDT on 24 August 2016 ()
Where
3 km (2 mi) south-southwest of Signal Hill, CA · earthquakes near Signal Hill
Magnitude
M 1.5 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Orange County, 40 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 3731 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 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.

Earthquakes near other towns within 30 km: Long Beach, Seal Beach, Rossmoor, Lakewood, Carson, Los Alamitos.

How big was it?

This earthquake released about 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 · 24 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 · 38 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 33.7810, -118.1860. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 40 km (25 mi) ESE earthquakes near Orange County
Los Angeles County, CA 47 km (29 mi) N earthquakes near Los Angeles County
Ventura County, CA 108 km (67 mi) NW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 2.2 2km ENE of Inglewood, CA
  2. 2.8 30km WSW of Rancho Palos Verdes, CA
  3. 2.4 1km ENE of Brea, CA
  4. 1.7 7km WSW of Huntington Beach, CA
  5. 1.6 2km N of Costa Mesa, CA
  6. 2.1 7km WSW of Huntington Beach, CA
  7. 1.8 18km SSW of Rancho Palos Verdes, CA
  8. 2.6 31km WSW of Rancho Palos Verdes, CA
  9. 2.1 7km WSW of Santa Monica, CA
  10. 1.9 19km S of Malibu Beach, CA
  11. 1.7 6km SW of Chino Hills, CA
  12. 1.6 4km N of Yorba Linda, CA
  13. 2.3 14km SSE of Malibu Beach, CA
  14. 1.6 4km WSW of Compton, CA
  15. 2.5 2km NNE of Costa Mesa, 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.