QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near Loma Linda, CA

No earthquake was likely felt in Loma Linda in the 24 hours to 9:49 pm PST (05:49 UTC). The last one was M 2.1, 2 km (1 mi) SE, at 10:40 am PDT on 31 October 2026, estimated intensity II (weak) in town. Every earthquake near Loma Linda

This page: a magnitude 3.0 earthquake was recorded 2 km (1 mi) east-southeast of Loma Linda, CA, at 11:39 pm PDT on 8 October 2017 (06:39 UTC), 18 km deep. 338 people have reported feeling it to USGS.

USGS: 2km ESE of Loma Linda, CA

6 km (4 mi) WSW of Redlands, CA · 108 km (67 mi) E of Los Angeles, CA

11:39 pm PDT, Oct 8, 2017 · · 18 km deep · released about 800 lb of TNT

10 km30 km60 km120 km N Orange County 64 kmLos Angeles County 96 kmRiverside County 119 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
11:39 pm PDT on 8 October 2017 ()
Where
2 km (1 mi) east-southeast of Loma Linda, CA · earthquakes near Loma Linda
Magnitude
M 3.0 (ml)
Depth
18 km below the surface
Felt
338 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
Orange County, 64 km SW
Nearest mapped fault
San Jacinto 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 3212 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 29 km (18 mi) from the epicentre. In Loma Linda, 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: Loma Linda 2 km, intensity II · Redlands 5 km, intensity II · Colton 8 km, intensity II · San Bernardino 9 km, intensity II · Highland 10 km, intensity II · Mentone 10 km, intensity II · Moreno Valley 11 km, intensity II · Rialto 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 800 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 420,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 19,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 13,000× the energy of this one
  4. This earthquake M 3.0 about 800 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 2016-01-06 — about 140 times the energy of this one.

Before 2016, the USGS record lists 24 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 40 km SE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 42 km ENE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 6 km NNW of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 41 km SSW of this epicentre
  5. 5.6 7km ENE of Running Springs, CA · 29 km NE 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 34.0407, -117.2388. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 64 km (40 mi) SW earthquakes near Orange County
Los Angeles County, CA 96 km (59 mi) W earthquakes near Los Angeles County
Riverside County, CA 119 km (74 mi) ESE earthquakes near Riverside County
San Diego County, CA 121 km (75 mi) SSE earthquakes near San Diego County
San Bernardino County, CA 133 km (83 mi) NE earthquakes near San Bernardino County

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

Aftershocks so far

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

  1. 2.5 2km NW of Big Bear City, CA
  2. 1.9 4km SE of Home Gardens, CA
  3. 1.6 4km S of Redlands, CA
  4. 1.6 9km NNW of Big Bear Lake, CA
  5. 1.9 5km N of Cabazon, CA
  6. 1.7 9km ESE of Big Bear City, CA
  7. 2.1 1km S of Loma Linda, CA
  8. 1.9 4km SE of Home Gardens, CA
  9. 1.9 5km SE of Loma Linda, CA
  10. 1.8 4km N of Beaumont, CA
  11. 2.2 4km NNW of Valle Vista, CA
  12. 1.9 5km NNW of Lake Elsinore, CA
  13. 1.8 2km NE of Redlands, CA
  14. 1.7 13km NNE of Yucaipa, CA
  15. 1.6 8km ESE of Yorba 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.