QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near La Puente, CA

No earthquake was likely felt in La Puente in the 24 hours to 5:17 am PST (13:17 UTC). The last one was M 3.2, 34 km (21 mi) SW, at 12:44 am PDT on 9 October 2026, estimated intensity II (weak) in town; 1,090 felt reports to USGS. Every earthquake near La Puente

This page: a magnitude 1.8 earthquake was recorded in La Puente, CA, at 7:50 pm PDT on 16 August 2021 (02:50 UTC), 9.3 km deep.

USGS: 1km NNW of La Puente, CA

5 km (3 mi) SW of West Covina, CA · 42 km (26 mi) E of Los Angeles, CA

7:50 pm PDT, Aug 16, 2021 · · 9.3 km deep · released about 15 lb of TNT

Every earthquake near La Puente Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Los Angeles County 34 kmOrange County 42 kmVentura County 114 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
7:50 pm PDT on 16 August 2021 ()
Where
in La Puente, CA · earthquakes near La Puente
Magnitude
M 1.8 (ml)
Depth
9.3 km below the surface
Felt
no reports yet
Nearest
Los Angeles County, 34 km WNW
Nearest mapped fault
Sierra Madre fault, 12 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 1913 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. 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 Puente in town, intensity II · Hacienda Heights 4 km, intensity II · West Covina 5 km, intensity II · Baldwin Park 6 km, intensity II · Rowland Heights 7 km, intensity II · El Monte 8 km, intensity II · Walnut 8 km, intensity II · South El Monte 9 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 13,000 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1933 Long Beach, California Earthquake · 44 km S of this epicentre
  2. 5.9 The 1987 Whittier Narrows, California Earthquake · 12 km WNW of this epicentre
  3. 5.8 The 1991 Sierra Madre, California Earthquake · 27 km N of this epicentre
  4. 5.5 The 1990 Upland, California Earthquake · 27 km ENE of this epicentre
  5. 5.4 5km S of Chino Hills, CA · 19 km ESE 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 34.0282, -117.9543. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Los Angeles County, CA 34 km (21 mi) WNW earthquakes near Los Angeles County
Orange County, CA 42 km (26 mi) SSE earthquakes near Orange County
Ventura County, CA 114 km (71 mi) WNW earthquakes near Ventura County
San Diego County, CA 156 km (97 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

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

  1. 1.8 4km WSW of East Los Angeles, CA
  2. 1.5 4km SE of Home Gardens, CA
  3. 1.6 2km SSW of Sherman Oaks, CA
  4. 1.6 2km ESE of Anaheim, CA
  5. 1.6 2km ESE of Anaheim, CA
  6. 1.6 2km ESE of Lawndale, CA
  7. 1.5 5km SE of Home Gardens, CA
  8. 1.6 5km NNE of Fontana, CA
  9. 2.0 3km WSW of East Los Angeles, CA
  10. 3.6 3km WSW of East Los Angeles, CA
  11. 2.0 4km SE of Home Gardens, CA
  12. 2.4 1km NW of View Park-Windsor Hills, CA
  13. 1.9 3km WNW of Fontana, CA
  14. 1.8 1km S of Commerce, CA
  15. 1.5 4km NW 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.