QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3ml

Earthquake near Mentone, CA

No earthquake was likely felt in Mentone in the 24 hours to 4:38 am PST (12:38 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 3.3 earthquake was recorded 3 km (2 mi) south of Mentone, CA, at 5:47 pm PST on 14 February 2018 (01:47 UTC), 13 km deep. 572 people have reported feeling it to USGS.

USGS: 3km S of Mentone, CA

in Redlands, CA · 117 km (73 mi) E of Los Angeles, CA

5:47 pm PST, Feb 14, 2018 · · 13 km deep · released about 1.5 tons of TNT

Every earthquake near Mentone Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 72 kmLos Angeles County 105 kmRiverside County 111 kmSan Diego County 118 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
5:47 pm PST on 14 February 2018 ()
Where
3 km (2 mi) south of Mentone, CA · earthquakes near Mentone
Magnitude
M 3.3 (ml)
Depth
13 km below the surface
Felt
572 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
Nearest
Orange County, 72 km SW
Nearest mapped fault
Crafton Hills 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 3103 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 52 km (32 mi) from the epicentre. In Mentone, 3 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: Mentone 3 km, intensity III · Redlands 4 km, intensity III · Yucaipa 9 km, intensity III · Loma Linda 11 km, intensity III · Highland 11 km, intensity III · Moreno Valley 15 km, intensity III · San Bernardino 15 km, intensity III · Colton 16 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1.5 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 110,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,500× the energy of this one
  4. This earthquake M 3.3 about 1.5 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.2× 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 4.4 on 2016-01-06 — about 38 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 · 35 km SSE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 34 km ENE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 12 km WNW of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 45 km SSW of this epicentre
  5. 6.0 The 1986 North Palm Springs, California Earthquake · 49 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 34.0448, -117.1400. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 72 km (45 mi) SW earthquakes near Orange County
Los Angeles County, CA 105 km (65 mi) W earthquakes near Los Angeles County
Riverside County, CA 111 km (69 mi) ESE earthquakes near Riverside County
San Diego County, CA 118 km (74 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

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

  1. 2.5 3km ENE of Upland, CA
  2. 1.7 7km N of Big Bear City, CA
  3. 1.5 9km NE of Big Bear City, CA
  4. 2.3 5km SSE of Mentone, CA
  5. 1.9 11km SSE of Lucerne Valley, CA
  6. 2.6 1km SSW of Loma Linda, CA
  7. 1.8 3km SE of San Jacinto, CA
  8. 1.7 4km SE of San Jacinto, CA
  9. 2.0 4km SE of San Jacinto, CA
  10. 2.6 7km NW of Big Bear Lake, CA
  11. 1.7 3km SE of San Jacinto, CA
  12. 1.8 2km E of Menifee, CA
  13. 1.7 8km N of Big Bear City, CA
  14. 1.6 12km NE of Trabuco Canyon, CA
  15. 2.7 3km NNW of Beaumont, 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.