QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Running Springs, CA

No earthquake was likely felt in Running Springs in the 24 hours to 5:31 am PST (13:31 UTC). The last one was M 2.0, 13 km (8 mi) WSW, at 3:40 pm PDT on 22 September 2026, estimated intensity II (weak) in town; 14 felt reports to USGS. Every earthquake near Running Springs

This page: a magnitude 1.7 earthquake was recorded 13 km (8 mi) northeast of Running Springs, CA, at 2:26 am PST on 20 February 2023 (10:26 UTC), 9.0 km deep.

USGS: 12km NE of Running Springs, CA

24 km (15 mi) NNE of Highland, CA · 131 km (81 mi) ENE of Los Angeles, CA

2:26 am PST, Feb 20, 2023 · · 9.0 km deep · released about 9.3 lb of TNT

Every earthquake near Running Springs Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 98 kmSan Bernardino County 99 kmLos Angeles County 114 kmRiverside County 114 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
2:26 am PST on 20 February 2023 ()
Where
13 km (8 mi) northeast of Running Springs, CA · earthquakes near Running Springs
Magnitude
M 1.7 (ml)
Depth
9.0 km below the surface
Felt
no reports yet
Nearest
Orange County, 98 km SW
Nearest mapped fault
North Frontal thrust system, 13 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 1360 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 8 km (5 mi) from the epicentre. In Running Springs, 13 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 Lake, Lake Arrowhead, Lucerne Valley, Big Bear City, Crestline, Highland.

How big was it?

This earthquake released about 9.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 100× the energy of this one
  4. This earthquake M 1.7 about 9.3 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 18,000 times the energy of this one.

Before 2016, the USGS record lists 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.3 The 1992 Big Bear, California Earthquake · 22 km ESE of this epicentre
  2. 6.2 3 km SE of San Bernardino, California · 31 km SW of this epicentre
  3. 5.6 7km ENE of Running Springs, CA · 7 km S of this epicentre
  4. 5.5 11km SSE of Big Bear Lake, California · 23 km SE of this epicentre
  5. 5.4 26km NNW of Yucca Valley, CA · 48 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 34.3005, -117.0318. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 98 km (61 mi) SW earthquakes near Orange County
San Bernardino County, CA 99 km (62 mi) NE earthquakes near San Bernardino County
Los Angeles County, CA 114 km (71 mi) W earthquakes near Los Angeles County
Riverside County, CA 114 km (71 mi) ESE earthquakes near Riverside 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. 2.8 8km NE of Cabazon, CA
  2. 1.8 9km NE of Cabazon, CA
  3. 1.6 2km S of Lytle Creek, CA
  4. 2.1 3km SE of Loma Linda, CA
  5. 2.1 12km WNW of Morongo Valley, CA
  6. 1.6 3km S of Lytle Creek, CA
  7. 3.6 12km NNE of Banning, CA
  8. 1.7 3km S of Lytle Creek, CA
  9. 2.0 20km ENE of Big Bear City, CA
  10. 2.0 8km NW of Morongo Valley, CA
  11. 1.5 6km NNW of Cabazon, CA
  12. 1.5 2km NE of Loma Linda, CA
  13. 1.5 0km SSW of Calimesa, CA
  14. 1.6 6km SSE of Moreno Valley, CA
  15. 1.8 4km SW of Redlands, 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.