QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Seal Beach, CA

No earthquake was likely felt in Seal Beach in the 24 hours to 4:02 am PST (12:02 UTC). The last one was M 3.2, 9 km (6 mi) NW, at 12:44 am PDT on 9 October 2026, estimated intensity III (weak) in town; 1,090 felt reports to USGS. Every earthquake near Seal Beach

This page: a magnitude 1.8 earthquake was recorded 9 km (5 mi) south of Seal Beach, CA, at 10:05 am PST on 5 January 2018 (18:05 UTC), 15 km deep.

USGS: 9km S of Seal Beach, CA

9 km (6 mi) WSW of Huntington Beach, CA · 49 km (31 mi) SE of Los Angeles, CA

10:05 am PST, Jan 5, 2018 · · 15 km deep · released about 16 lb of TNT

Every earthquake near Seal Beach Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 29 kmLos Angeles County 61 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
10:05 am PST on 5 January 2018 ()
Where
9 km (5 mi) south of Seal Beach, CA · earthquakes near Seal Beach
Magnitude
M 1.8 (ml)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Orange County, 29 km E
Nearest mapped fault
Newport-Inglewood-Rose Canyon fault, 6 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 3233 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 Seal Beach, 9 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: Huntington Beach, Westminster, Rossmoor, Fountain Valley, Long Beach, Los Alamitos.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× the energy of this one
  4. This earthquake M 1.8 about 16 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 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 10 km ESE of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 44 km N of this epicentre
  3. 5.4 5km S of Chino Hills, CA · 44 km NE of this epicentre
  4. 5.3 7km W of Newport Beach, CA · 10 km ESE of this epicentre
  5. 5.2 2km WSW of Rosemead, CA · 46 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 33.6637, -118.0947. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 29 km (18 mi) E earthquakes near Orange County
Los Angeles County, CA 61 km (38 mi) NNW earthquakes near Los Angeles County
Ventura County, CA 123 km (76 mi) NW earthquakes near Ventura County

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

Aftershocks so far

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

  1. 2.0 4km SSW of Baldwin Hills, CA
  2. 1.7 2km E of Foothill Ranch, CA
  3. 1.8 4km WSW of Irvine, CA
  4. 1.5 24km SW of Dana Point, CA
  5. 1.8 1km NNW of Rolling Hills Estates, CA
  6. 1.7 2km SSW of Yorba Linda, CA
  7. 1.6 1km E of Baldwin Hills, CA
  8. 1.5 1km NE of Pico Rivera, CA
  9. 2.0 4km E of Lennox, CA
  10. 1.5 4km WNW of Willowbrook, CA
  11. 2.7 2km ENE of La Habra, CA
  12. 2.0 2km S of Newport Beach, CA
  13. 1.6 1km NNE of Huntington Park, CA
  14. 1.7 9km SW of Rancho Palos Verdes, CA
  15. 1.6 8km ESE of North Tustin, 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.