QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near El Centro, CA

No earthquake was likely felt in El Centro in the 24 hours to 2:50 am PST (10:50 UTC). The last one was M 4.9, 54 km (33 mi) SE, at 10:27 am PST on 3 November 2026, estimated intensity III (weak) in town; 321 felt reports to USGS. Every earthquake near El Centro

This page: a magnitude 1.5 earthquake was recorded 34 km (21 mi) west-southwest of El Centro, CA, at 2:25 am PST on 23 December 2017 (10:25 UTC), 10 km deep.

USGS: 9km ESE of Ocotillo, CA

2:25 am PST, Dec 23, 2017 · · 10 km deep · released about 6.2 lb of TNT

10 km30 km60 km120 km N Imperial County 64 kmSan Diego County 89 kmRiverside County 115 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
2:25 am PST on 23 December 2017 ()
Where
34 km (21 mi) west-southwest of El Centro, CA · earthquakes near El Centro
Magnitude
M 1.5 (ml)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Imperial County, 64 km NE
Nearest mapped fault
Elsinore fault, 3 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 3234 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 3 km (2 mi) from the epicentre. In El Centro, 34 km away, the estimate is intensity I (not felt). 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: Seeley.

How big was it?

This earthquake released about 6.2 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 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.5 about 6.2 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 4.0 on 2016-07-31 — about 5,400 times the energy of this one.

Before 2016, the USGS record lists 31 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.6 The 1942 Fish Creek Mountains, California Earthquake · 33 km NNE of this epicentre
  2. 6.6 The 1987 Superstition Hills, California Earthquake · 35 km N of this epicentre
  3. 6.3 The 1906 Imperial Valley, California Earthquake · 44 km ENE of this epicentre
  4. 6.2 The 1987 Elmore Ranch, California Earthquake · 45 km NNE of this epicentre
  5. 6.0 The 1915 Imperial Valley, California Earthquakes (First Major Event) · 39 km ENE 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 32.6997, -115.9042. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Imperial County, CA 64 km (40 mi) NE earthquakes near Imperial County
San Diego County, CA 89 km (55 mi) WNW earthquakes near San Diego County
Riverside County, CA 115 km (71 mi) N earthquakes near Riverside County

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

Aftershocks so far

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

  1. 2.0 7km SSW of Brawley, CA
  2. 2.3 8km S of Brawley, CA
  3. 1.7 7km NE of Imperial, CA
  4. 1.9 8km NE of Imperial, CA
  5. 2.1 8km S of Brawley, CA
  6. 1.6 14km WNW of Progreso, B.C., MX
  7. 2.4 17km ESE of Ocotillo, CA
  8. 2.1 11km S of Progreso, B.C., MX
  9. 1.9 5km NNE of Imperial, CA
  10. 1.8 10km S of Progreso, B.C., MX
  11. 1.5 6km S of Brawley, CA
  12. 2.0 12km NW of Progreso, B.C., MX
  13. 1.5 8km W of Progreso, B.C., MX
  14. 2.0 5km S of Brawley, CA
  15. 1.8 3km NNW of El Centro, 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.