QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Morongo Valley, CA

No earthquake was likely felt in Morongo Valley in the 24 hours to 11:43 pm PST (07:43 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 1.5 earthquake was recorded 12 km (7 mi) north-northeast of Morongo Valley, CA, at 12:00 pm PDT on 4 July 2018 (19:00 UTC), 2.2 km deep.

USGS: 12km NNE of Morongo Valley, CA

81 km (50 mi) ENE of Riverside, CA · 36 km (22 mi) NNW of Cathedral City, CA

12:00 pm PDT, Jul 4, 2018 · · 2.2 km deep · released about 5.9 lb of TNT

10 km30 km60 km120 km N Riverside County 69 kmSan Bernardino County 86 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
12:00 pm PDT on 4 July 2018 ()
Where
12 km (7 mi) north-northeast of Morongo Valley, CA · earthquakes near Morongo Valley
Magnitude
M 1.5 (ml)
Depth
2.2 km below the surface
Felt
no reports yet
Nearest
Riverside County, 69 km SE
Nearest mapped fault
Pinto Mountain fault (includes Morongo Valley fault), 7 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 10 km (6 mi) from the epicentre. In Morongo Valley, 12 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: Yucca Valley, Desert Hot Springs, Joshua Tree, Garnet, Desert Edge, Big Bear City.

How big was it?

This earthquake released about 5.9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,800,000× the energy of this one
  3. Around the size people start to feel M 3.0 160× the energy of this one
  4. This earthquake M 1.5 about 5.9 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 4.5 on 2018-05-08 — about 28,000 times the energy of this one.

Before 2016, the USGS record lists 35 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.3 The 1992 Landers, California Earthquake · 12 km ENE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 26 km WNW of this epicentre
  3. 6.1 The 1992 Joshua Tree, California Earthquake · 30 km SE of this epicentre
  4. 6.0 The 1948 Desert Hot Springs, California Earthquake · 28 km SE of this epicentre
  5. 6.0 The 1986 North Palm Springs, California Earthquake · 17 km SSW 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 34.1490, -116.5550. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Riverside County, CA 69 km (43 mi) SE earthquakes near Riverside County
San Bernardino County, CA 86 km (53 mi) NNE earthquakes near San Bernardino County
Orange County, CA 124 km (77 mi) WSW earthquakes near Orange County

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

Aftershocks so far

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

  1. 1.6 1km SSW of Big Bear Lake, CA
  2. 1.7 1km SSW of Big Bear Lake, CA
  3. 2.1 9km SW of Morongo Valley, CA
  4. 1.7 4km WNW of Cabazon, CA
  5. 2.7 18km ENE of Thousand Palms, CA
  6. 1.9 3km SSE of Yucca Valley, CA
  7. 1.8 18km ENE of Thousand Palms, CA
  8. 1.6 8km NE of Cabazon, CA
  9. 1.5 18km ENE of Thousand Palms, CA
  10. 3.0 18km ENE of Thousand Palms, CA
  11. 1.6 18km ENE of Thousand Palms, CA
  12. 1.9 8km SSW of Big Bear Lake, CA
  13. 1.5 9km SSW of Big Bear Lake, CA
  14. 1.8 9km SSW of Big Bear Lake, CA
  15. 1.6 12km SSE of Big Bear Lake, 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.