QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

Earthquake near Colton, CA

No earthquake was likely felt in Colton in the 24 hours to 11:35 pm PST (07:35 UTC). The last one was M 2.1, 8 km (5 mi) SE, at 10:40 am PDT on 31 October 2026, estimated intensity II (weak) in town. Every earthquake near Colton

This page: a magnitude 2.2 earthquake was recorded 2 km (1 mi) north of Colton, CA, at 5:38 pm PDT on 28 September 2017 (00:38 UTC), 17 km deep.

USGS: 2km N of Colton, CA

5 km (3 mi) SSW of San Bernardino, CA · in Colton, CA

5:38 pm PDT, Sep 28, 2017 · · 17 km deep · released about 69 lb of TNT

Every earthquake near Colton Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 63 kmLos Angeles County 88 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
5:38 pm PDT on 28 September 2017 ()
Where
2 km (1 mi) north of Colton, CA · earthquakes near Colton
Magnitude
M 2.2 (ml)
Depth
17 km below the surface
Felt
no reports yet
Nearest
Orange County, 63 km SW
Nearest mapped fault
San Jacinto fault, 2 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 3303 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 Colton, 2 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.

Likely felt in: Colton 2 km, intensity II · San Bernardino 3 km, intensity II · Rialto 5 km, intensity II · Loma Linda 7 km, intensity II · Muscoy 7 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 69 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 220,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 150,000× the energy of this one
  3. Around the size people start to feel M 3.0 14× the energy of this one
  4. This earthquake M 2.2 about 69 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 1,700 times the energy of this one.

Before 2016, the USGS record lists 21 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 49 km SE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 46 km ENE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 5 km E of this epicentre
  4. 6.0 The 1910 Lake Elsinore, California Earthquake · 45 km S of this epicentre
  5. 5.6 7km ENE of Running Springs, CA · 30 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 34.0942, -117.3130. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 63 km (39 mi) SW earthquakes near Orange County
Los Angeles County, CA 88 km (55 mi) W earthquakes near Los Angeles County
San Diego County, CA 129 km (80 mi) SSE earthquakes near San Diego County
San Bernardino County, CA 134 km (83 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

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

  1. 1.6 3km SE of Loma Linda, CA
  2. 2.6 3km SE of Loma Linda, CA
  3. 1.6 3km ESE of Loma Linda, CA
  4. 2.7 5km E of Calimesa, CA
  5. 2.7 2km ESE of Loma Linda, CA
  6. 1.5 5km ENE of Rancho Cucamonga, CA
  7. 1.5 3km ESE of Loma Linda, CA
  8. 2.5 10km N of Lytle Creek, CA
  9. 1.7 5km NE of Yorba Linda, CA
  10. 2.3 1km NNW of Colton, CA
  11. 1.5 6km N of Big Bear City, CA
  12. 1.9 5km SSE of Home Gardens, CA
  13. 1.5 2km W of San Jacinto, CA
  14. 2.2 4km SE of Yucaipa, CA
  15. 1.7 14km SW of Lucerne Valley, 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.