QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Mentone, CA

No earthquake was likely felt in Mentone in the 24 hours to 5:01 am PST (13:01 UTC). The last one was M 2.0, 9 km (6 mi) S, at 10:33 pm PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Mentone

This page: a magnitude 2.3 earthquake was recorded 5 km (3 mi) south-southeast of Mentone, CA, at 11:38 pm PDT on 17 March 2018 (06:38 UTC), 11 km deep.

USGS: 5km SSE of Mentone, CA

6 km (4 mi) ESE of Redlands, CA · 120 km (74 mi) E of Los Angeles, CA

11:38 pm PDT, Mar 17, 2018 · · 11 km deep · released about 74 lb of TNT

Every earthquake near Mentone Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 73 kmLos Angeles County 107 kmRiverside County 108 kmSan Diego 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
11:38 pm PDT on 17 March 2018 ()
Where
5 km (3 mi) south-southeast of Mentone, CA · earthquakes near Mentone
Magnitude
M 2.3 (ml)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Orange County, 73 km WSW
Nearest mapped fault
Crafton Hills fault, 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 3030 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 Mentone, 5 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: Mentone 5 km, intensity II · Yucaipa 6 km, intensity II · Redlands 7 km, intensity II · Loma Linda 14 km, intensity II · Highland 14 km, intensity II · Moreno Valley 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 74 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 140,000× the energy of this one
  3. Around the size people start to feel M 3.0 13× the energy of this one
  4. This earthquake M 2.3 about 74 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 1,600 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 · 32 km SSE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 33 km NE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 15 km WNW of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 45 km SW of this epicentre
  5. 6.0 The 1986 North Palm Springs, California Earthquake · 47 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 34.0287, -117.1120. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 73 km (45 mi) WSW earthquakes near Orange County
Los Angeles County, CA 107 km (67 mi) W earthquakes near Los Angeles County
Riverside County, CA 108 km (67 mi) ESE earthquakes near Riverside County
San Diego County, CA 116 km (72 mi) SSE earthquakes near San Diego County
San Bernardino County, CA 126 km (78 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

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

  1. 1.7 8km E of Running Springs, CA
  2. 1.6 5km SE of Home Gardens, CA
  3. 1.5 3km WSW of Morongo Valley, CA
  4. 1.8 14km WNW of Morongo Valley, CA
  5. 1.9 3km S of Lytle Creek, CA
  6. 2.0 3km NNE of Norco, CA
  7. 1.6 5km SE of Loma Linda, CA
  8. 2.1 11km NNE of Trabuco Canyon, CA
  9. 2.5 11km NE of Trabuco Canyon, CA
  10. 2.4 2km W of Loma Linda, CA
  11. 1.9 4km ENE of Calimesa, CA
  12. 2.1 3km ENE of Calimesa, CA
  13. 2.3 4km ENE of Calimesa, CA
  14. 1.8 10km NNW of Big Bear Lake, CA
  15. 3.2 6km NNE of Moreno Valley, 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.