QuakeIndex

Earthquake · automatic estimate, may change

M 1.8ml

Earthquake near Jurupa Valley, CA

No earthquake was likely felt in Jurupa Valley in the 24 hours to 1:16 pm PST (21:16 UTC). The last one was M 1.6, 3 km (2 mi) N, at 6:22 am PST on 12 November 2026, estimated intensity II (weak) in town. Every earthquake near Jurupa Valley

This page: a magnitude 1.8 earthquake was recorded 3 km (2 mi) north-northwest of Jurupa Valley, CA, at 7:31 am PDT on 31 August 2019 (14:31 UTC), 1.9 km deep. 3 people have reported feeling it to USGS. The magnitude and location are an automatic first estimate and may change.

USGS: 3km NNW of Mira Loma, CA

6 km (4 mi) WNW of Jurupa Valley, CA · 81 km (51 mi) E of Los Angeles, CA

7:31 am PDT, Aug 31, 2019 · · 1.9 km deep · released about 15 lb of TNT

Every earthquake near Jurupa Valley Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 44 kmLos Angeles County 71 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
7:31 am PDT on 31 August 2019 ()
Where
3 km (2 mi) north-northwest of Jurupa Valley, CA · earthquakes near Jurupa Valley
Magnitude
M 1.8 (ml)
Depth
1.9 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Orange County, 44 km SSW
Nearest mapped fault
Red Hill-Etiwanda Avenue fault, 13 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 2631 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 13 km (8 mi) from the epicentre. In Jurupa Valley, 3 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: Pedley 7 km, intensity II · Eastvale 7 km, intensity II · Norco 10 km, intensity II · Rubidoux 11 km, intensity II · Rancho Cucamonga 12 km, intensity II · Fontana 12 km, intensity II · Ontario 13 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 4.4 on 2018-08-29 — about 7,400 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 · 26 km ENE of this epicentre
  2. 6.0 The 1910 Lake Elsinore, California Earthquake · 37 km SSE of this epicentre
  3. 5.5 The 1990 Upland, California Earthquake · 21 km NW of this epicentre
  4. 5.4 5km S of Chino Hills, CA · 23 km WSW of this epicentre
  5. 5.3 Near San Bernardino, California · 44 km ENE 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 34.0163, -117.5270. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 44 km (28 mi) SSW earthquakes near Orange County
Los Angeles County, CA 71 km (44 mi) WNW earthquakes near Los Angeles County
San Diego County, CA 131 km (81 mi) SSE 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. 1.7 2km NNW of Loma Linda, CA
  2. 1.6 3 km SE of Home Gardens, CA
  3. 1.7 5km SSW of Redlands, CA
  4. 2.4 11km WNW of Lake Elsinore, CA
  5. 2.9 11km WNW of Lake Elsinore, CA
  6. 1.7 3km NNW of Mira Loma, CA
  7. 1.7 5km SE of Home Gardens, CA
  8. 2.6 11km WNW of Lake Elsinore, CA
  9. 1.5 5km SSE of Home Gardens, CA
  10. 1.7 7km NE of Moreno Valley, CA
  11. 1.6 8km ESE of Yorba Linda, CA
  12. 1.8 6km ENE of North Tustin, CA
  13. 1.7 1km SW of Calimesa, CA
  14. 1.6 3km NNW of Mira Loma, CA
  15. 1.6 1km ENE of Wrightwood, 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.