QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

Earthquake near La Verne, CA

No earthquake was likely felt in La Verne in the 24 hours to 1:05 pm PST (21:05 UTC). The last one was M 3.2, 19 km (12 mi) ESE, at 5:37 am PDT on 2 September 2026, estimated intensity III (weak) in town; 730 felt reports to USGS. Every earthquake near La Verne

This page: a magnitude 2.1 earthquake was recorded 4 km (2 mi) north of La Verne, CA, at 9:26 pm PDT on 4 September 2018 (04:26 UTC), 5.1 km deep. 38 people have reported feeling it to USGS.

USGS: 4km N of La Verne, CA

7 km (4 mi) E of Glendora, CA · 60 km (37 mi) ENE of Los Angeles, CA

9:26 pm PDT, Sep 4, 2018 · · 5.1 km deep · released about 43 lb of TNT

Every earthquake near La Verne Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Los Angeles County 46 kmOrange 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
9:26 pm PDT on 4 September 2018 ()
Where
4 km (2 mi) north of La Verne, CA · earthquakes near La Verne
Magnitude
M 2.1 (ml)
Depth
5.1 km below the surface
Felt
38 reports · strongest reported intensity III
Nearest
Los Angeles County, 46 km W
Nearest mapped fault
Sierra Madre fault, under 1 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 2942 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 16 km (10 mi) from the epicentre. In La Verne, 4 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: La Verne 4 km, intensity II · San Dimas 5 km, intensity II · Claremont 6 km, intensity II · Glendora 9 km, intensity II · Pomona 9 km, intensity II · Montclair 10 km, intensity II · Covina 12 km, intensity II · Upland 12 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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 4.4 on 2018-08-29 — about 2,600 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 · 47 km E of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 29 km WSW of this epicentre
  3. 5.8 The 1991 Sierra Madre, California Earthquake · 25 km NW of this epicentre
  4. 5.5 The 1990 Upland, California Earthquake · 7 km E of this epicentre
  5. 5.4 5km S of Chino Hills, CA · 21 km S 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 34.1355, -117.7718. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Los Angeles County, CA 46 km (28 mi) W earthquakes near Los Angeles County
Orange County, CA 51 km (32 mi) S earthquakes near Orange County

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

Aftershocks so far

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

  1. 1.6 1km SSW of Colton, CA
  2. 1.5 5km SSE of Home Gardens, CA
  3. 1.5 2km NE of Whittier, CA
  4. 2.3 4km WNW of Devore, CA
  5. 1.5 4km WSW of Lytle Creek, CA
  6. 1.9 1km NNE of Loma Linda, CA
  7. 2.0 4km SSW of La Mirada, CA
  8. 2.3 3km SW of La Mirada, CA
  9. 2.5 4km WNW of Devore, CA
  10. 1.8 10km W of Corona, CA
  11. 1.6 3km SE of Home Gardens, CA
  12. 1.8 5km SSE of Home Gardens, CA
  13. 1.5 3km E of Colton, CA
  14. 1.5 4km WNW of Lytle Creek, CA
  15. 1.9 2km SSE of Loma Linda, 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.