QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Claremont, CA

No earthquake was likely felt in Claremont in the 24 hours to 5:12 am PST (13:12 UTC). The last one was M 2.7, 22 km (14 mi) E, at 1:09 am PDT on 8 October 2026, estimated intensity II (weak) in town; 158 felt reports to USGS. Every earthquake near Claremont

This page: a magnitude 1.6 earthquake was recorded 2 km (1 mi) north of Claremont, CA, at 4:39 pm PDT on 12 June 2021 (23:39 UTC), 3.7 km deep.

USGS: 2km N of Claremont, CA

5 km (3 mi) W of Upland, CA · 65 km (40 mi) E of Los Angeles, CA

4:39 pm PDT, Jun 12, 2021 · · 3.7 km deep · released about 7.3 lb of TNT

Every earthquake near Claremont Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 49 kmLos Angeles County 51 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
4:39 pm PDT on 12 June 2021 ()
Where
2 km (1 mi) north of Claremont, CA · earthquakes near Claremont
Magnitude
M 1.6 (ml)
Depth
3.7 km below the surface
Felt
no reports yet
Nearest
Orange County, 49 km S
Nearest mapped fault
Sierra Madre fault, 2 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 1976 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 10 km (6 mi) from the epicentre. In Claremont, 2 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: Claremont 2 km, intensity II · La Verne 5 km, intensity II · Montclair 5 km, intensity II · Upland 7 km, intensity II · Pomona 7 km, intensity II · San Dimas 8 km, intensity II · Ontario 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 7.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.3 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 27,000 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.2 3 km SE of San Bernardino, California · 42 km E of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 34 km W of this epicentre
  3. 5.8 The 1991 Sierra Madre, California Earthquake · 31 km NW of this epicentre
  4. 5.5 The 1990 Upland, California Earthquake · 4 km NNE of this epicentre
  5. 5.4 5km S of Chino Hills, CA · 19 km SSW 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 34.1152, -117.7180. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 49 km (31 mi) S earthquakes near Orange County
Los Angeles County, CA 51 km (32 mi) W earthquakes near Los Angeles County

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

Aftershocks so far

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

  1. 2.6 5km NNE of Fontana, CA
  2. 2.6 5km SE of Loma Linda, CA
  3. 1.6 4km NE of Whittier, CA
  4. 1.6 4km SW of Highland, CA
  5. 1.9 4km SE of Home Gardens, CA
  6. 2.0 3km E of Loma Linda, CA
  7. 1.7 4km SE of Home Gardens, CA
  8. 1.7 2km ESE of Loma Linda, CA
  9. 1.7 4km N of Fontana, CA
  10. 1.6 4km N of Fontana, CA
  11. 1.5 6km S of Pearblossom, CA
  12. 1.8 3km SSE of Garden Grove, CA
  13. 1.8 3km SSE of Devore, CA
  14. 1.6 4km N of Rancho Cucamonga, CA
  15. 1.7 6km SSE of Home Gardens, 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.