QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Morongo Valley, CA

No earthquake was likely felt in Morongo Valley in the 24 hours to 12:15 am PST (08:15 UTC). The last one was M 3.6, 72 km (44 mi) S, at 12:31 am PDT on 19 August 2026, estimated intensity II (weak) in town; 165 felt reports to USGS. Every earthquake near Morongo Valley

This page: a magnitude 1.8 earthquake was recorded 16 km (10 mi) northwest of Morongo Valley, CA, at 4:46 pm PDT on 13 March 2018 (23:46 UTC), 1.6 km deep.

USGS: 16km NW of Morongo Valley, CA

68 km (42 mi) ENE of Riverside, CA · 34 km (21 mi) ENE of Yucaipa, CA

4:46 pm PDT, Mar 13, 2018 · · 1.6 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Riverside County 79 kmSan Bernardino County 92 kmOrange County 112 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
4:46 pm PDT on 13 March 2018 ()
Where
16 km (10 mi) northwest of Morongo Valley, CA · earthquakes near Morongo Valley
Magnitude
M 1.8 (ml)
Depth
1.6 km below the surface
Felt
no reports yet
Nearest
Riverside County, 79 km SE
Nearest mapped fault
Pinto Mountain fault (includes Morongo Valley fault), 8 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 14 km (9 mi) from the epicentre. In Morongo Valley, 16 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.

Earthquakes near other towns within 30 km: Big Bear City, Big Bear Lake, Yucca Valley, Cabazon, Desert Hot Springs, Banning.

How big was it?

This earthquake released about 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 6,900 times the energy of this one.

Before 2016, the USGS record lists 37 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.3 The 1992 Landers, California Earthquake · 25 km ENE of this epicentre
  2. 6.7 The 1918 San Jacinto, California Earthquake · 49 km SSW of this epicentre
  3. 6.3 The 1992 Big Bear, California Earthquake · 13 km WNW of this epicentre
  4. 6.1 The 1992 Joshua Tree, California Earthquake · 41 km ESE of this epicentre
  5. 6.0 The 1948 Desert Hot Springs, California Earthquake · 39 km ESE 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 34.1452, -116.7032. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Riverside County, CA 79 km (49 mi) SE earthquakes near Riverside County
San Bernardino County, CA 92 km (57 mi) NNE earthquakes near San Bernardino County
Orange County, CA 112 km (70 mi) WSW earthquakes near Orange 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. 4.5 11km N of Cabazon, CA
  2. 2.2 2km E of Big Bear Lake, CA
  3. 2.1 9km SW of Morongo Valley, CA
  4. 1.8 4km SSW of Idyllwild, CA
  5. 1.7 8km E of Running Springs, CA
  6. 1.5 3km WSW of Morongo Valley, CA
  7. 1.8 14km WNW of Morongo Valley, CA
  8. 1.6 5km SE of Loma Linda, CA
  9. 1.9 4km ENE of Calimesa, CA
  10. 2.1 3km ENE of Calimesa, CA
  11. 2.3 4km ENE of Calimesa, CA
  12. 1.8 10km NNW of Big Bear Lake, CA
  13. 1.5 6km ENE of Desert Hot Springs, CA
  14. 2.2 13km NNE of Thousand Palms, CA
  15. 3.9 13km NNE of Thousand Palms, 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.