QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Yorba Linda, CA

No earthquake was likely felt in Yorba Linda in the 24 hours to 3:42 am PST (11:42 UTC). The last one was M 1.8, 5 km (3 mi) ESE, at 9:16 pm PST on 3 November 2026, estimated intensity II (weak) in town. Every earthquake near Yorba Linda

This page: a magnitude 2.3 earthquake was recorded 11 km (7 mi) east of Yorba Linda, CA, at 10:25 am PDT on 7 July 2021 (17:25 UTC), 10 km deep. 3 people have reported feeling it to USGS.

USGS: 11km E of Yorba Linda, CA

6 km (4 mi) ENE of Anaheim, CA · 68 km (42 mi) ESE of Los Angeles, CA

10:25 am PDT, Jul 7, 2021 · · 10 km deep · released about 94 lb of TNT

Every earthquake near Yorba Linda Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 23 kmLos Angeles County 64 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
10:25 am PDT on 7 July 2021 ()
Where
11 km (7 mi) east of Yorba Linda, CA · earthquakes near Yorba Linda
Magnitude
M 2.3 (ml)
Depth
10 km below the surface
Felt
3 reports · strongest reported intensity II
Nearest
Orange County, 23 km SSW
Nearest mapped fault
Elsinore fault, 4 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 1953 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 17 km (11 mi) from the epicentre. In Yorba Linda, 11 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: Yorba Linda 11 km, intensity II · Corona 12 km, intensity II · North Tustin 15 km, intensity II · Chino Hills 15 km, intensity II · Norco 15 km, intensity II · Chino 16 km, intensity II · Eastvale 16 km, intensity II · Placentia 16 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 94 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 5.8 160,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 110,000× the energy of this one
  3. Around the size people start to feel M 3.0 10× the energy of this one
  4. This earthquake M 2.3 about 94 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 4.5 on 2020-09-19 — about 2,100 times the energy of this one.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 39 km SW of this epicentre
  2. 6.2 3 km SE of San Bernardino, California · 47 km ENE of this epicentre
  3. 6.0 The 1910 Lake Elsinore, California Earthquake · 33 km SE of this epicentre
  4. 5.9 The 1987 Whittier Narrows, California Earthquake · 41 km WNW of this epicentre
  5. 5.5 The 1990 Upland, California Earthquake · 30 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 33.8698, -117.6947. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 23 km (14 mi) SSW earthquakes near Orange County
Los Angeles County, CA 64 km (40 mi) NW earthquakes near Los Angeles County
San Diego County, CA 127 km (79 mi) SE earthquakes near San Diego 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. 1.8 5km SSE of Home Gardens, CA
  2. 1.9 3km NNW of Rancho Cucamonga, CA
  3. 1.5 5km N of Lake Elsinore, CA
  4. 1.8 5km NNW of Glen Avon, CA
  5. 2.3 9km N of Rancho Cucamonga, CA
  6. 2.0 9km SW of Lytle Creek, CA
  7. 1.6 4km SE of Rancho Cucamonga, CA
  8. 2.3 5km NE of Wildomar, CA
  9. 1.7 5km SSE of Home Gardens, CA
  10. 2.9 2km SSE of Lytle Creek, CA
  11. 1.8 5km NE of Wildomar, CA
  12. 2.6 3km NNW of La Verne, CA
  13. 2.1 5km SSE of Home Gardens, CA
  14. 1.6 5km NNE of Fontana, CA
  15. 2.6 5km NNE of Fontana, 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.