QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near Calimesa, CA

No earthquake was likely felt in Calimesa in the 24 hours to 4:36 am PST (12:36 UTC). The last one was M 2.0, 7 km (4 mi) WSW, at 10:33 pm PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Calimesa

This page: a magnitude 3.1 earthquake was recorded 4 km (2 mi) east of Calimesa, CA, at 11:46 am PDT on 26 July 2018 (18:46 UTC), 16 km deep. 15 people have reported feeling it to USGS.

USGS: 4km ENE of Calimesa, CA

in Yucaipa, CA · 128 km (80 mi) E of Los Angeles, CA

11:46 am PDT, Jul 26, 2018 · · 16 km deep · released about 1,200 lb of TNT

10 km30 km60 km120 km N Orange County 79 kmRiverside County 99 kmSan Diego County 111 kmLos Angeles County 116 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
11:46 am PDT on 26 July 2018 ()
Where
4 km (2 mi) east of Calimesa, CA · earthquakes near Calimesa
Magnitude
M 3.1 (ml)
Depth
16 km below the surface
Felt
15 reports · strongest reported intensity III
Measured shaking
intensity IV (ShakeMap)
Nearest
Orange County, 79 km WSW
Nearest mapped fault
San Gorgonio Pass fault, 3 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 2747 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 36 km (22 mi) from the epicentre. In Calimesa, 4 km away, the estimate is intensity III (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: Yucaipa 4 km, intensity III · Beaumont 9 km, intensity III · Mentone 13 km, intensity II · Banning 16 km, intensity II · Redlands 16 km, intensity II · Moreno Valley 21 km, intensity II · Highland 22 km, intensity II · Loma Linda 23 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 290,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,100× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.2× more

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 2018-05-08 — about 140 times the energy of this one.

Before 2016, the USGS record lists 23 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 27 km S of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 28 km NE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 24 km WNW of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 49 km SW of this epicentre
  5. 6.0 The 1986 North Palm Springs, California Earthquake · 38 km E 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 34.0037, -117.0195. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 79 km (49 mi) WSW earthquakes near Orange County
Riverside County, CA 99 km (61 mi) ESE earthquakes near Riverside County
San Diego County, CA 111 km (69 mi) SSE earthquakes near San Diego County
Los Angeles County, CA 116 km (72 mi) W earthquakes near Los Angeles County
San Bernardino County, CA 122 km (76 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

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

  1. 1.6 4km SE of Home Gardens, CA
  2. 2.2 2km NNE of Yucaipa, CA
  3. 1.5 5km SSE of Hemet, CA
  4. 3.0 6km E of Lucerne Valley, CA
  5. 1.5 2km SE of Home Gardens, CA
  6. 1.8 10km SSW of Idyllwild, CA
  7. 2.4 6km E of Lucerne Valley, CA
  8. 2.7 1km SSW of Big Bear Lake, CA
  9. 1.6 1km SSW of Big Bear Lake, CA
  10. 1.7 1km SSW of Big Bear Lake, CA
  11. 1.9 8km NE of Moreno Valley, CA
  12. 2.1 9km SW of Morongo Valley, CA
  13. 1.8 5km N of Fontana, CA
  14. 1.7 4km WNW of Cabazon, CA
  15. 1.9 0km NE 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.