QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Anza, CA

No earthquake was likely felt in Anza in the 24 hours to 12:31 pm PST (20:31 UTC). The last one was M 2.6, 17 km (10 mi) S, at 10:44 pm PST on 5 November 2026, estimated intensity II (weak) in town; 7 felt reports to USGS. Every earthquake near Anza

This page: a magnitude 1.6 earthquake was recorded 4 km (2 mi) east-northeast of Anza, CA, at 12:33 pm PST on 30 January 2023 (20:33 UTC), 16 km deep.

USGS: 4km ENE of Anza, CA

96 km (59 mi) NNE of San Diego, CA · 32 km (20 mi) SW of Palm Desert, CA

12:33 pm PST, Jan 30, 2023 · · 16 km deep · released about 7.3 lb of TNT

10 km30 km60 km120 km N Riverside County 61 kmSan Diego County 62 kmOrange County 106 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
12:33 pm PST on 30 January 2023 ()
Where
4 km (2 mi) east-northeast of Anza, CA · earthquakes near Anza
Magnitude
M 1.6 (ml)
Depth
16 km below the surface
Felt
no reports yet
Nearest
Riverside County, 61 km ENE
Nearest mapped fault
San Jacinto fault, under 1 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 1381 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Anza, 4 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: Idyllwild, Idyllwild-Pine Cove, Aguanga, Rancho Mirage, Cathedral City, Palm Desert.

How big was it?

This earthquake released about 7.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.3 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 5.2 on 2016-06-10 — about 250,000 times the energy of this one.

Before 2016, the USGS record lists 15 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 38 km NW of this epicentre
  2. 6.0 16km WSW of Oasis, CA · 40 km ESE of this epicentre
  3. 6.0 The 1986 North Palm Springs, California Earthquake · 48 km N of this epicentre
  4. 5.5 1km ENE of Borrego Springs, CA · 43 km SE of this epicentre
  5. 5.4 20km NNW of Borrego Springs, CA · 22 km SE 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 33.5667, -116.6368. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Riverside County, CA 61 km (38 mi) ENE earthquakes near Riverside County
San Diego County, CA 62 km (38 mi) SSW earthquakes near San Diego County
Orange County, CA 106 km (66 mi) W earthquakes near Orange County
Imperial County, CA 133 km (82 mi) ESE earthquakes near Imperial County

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

Aftershocks so far

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

  1. 2.3 6km WSW of Anza, CA
  2. 1.6 6km WSW of Anza, CA
  3. 2.1 6km WSW of Anza, CA
  4. 1.7 21km ESE of Anza, CA
  5. 2.0 5km NNE of Banning, CA
  6. 1.8 10km NW of San Jacinto, CA
  7. 1.8 3km SE of San Jacinto, CA
  8. 1.9 8km WSW of Idyllwild, CA
  9. 1.5 3km NNW of Cabazon, CA
  10. 1.9 5km SW of Palomar Observatory, CA
  11. 2.4 16km N of Borrego Springs, CA
  12. 1.7 14km SE of Anza, CA
  13. 2.0 14km SE of Anza, CA
  14. 2.6 5km S of Idyllwild, CA
  15. 2.3 14km SE of Anza, 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.