Earthquake near Anza, CA

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 37 km (23 mi) from the epicentre. In Anza, 20 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: Anza 20 km, intensity II · Borrego Springs 25 km, intensity II · La Quinta 28 km, intensity II · Palm Desert 31 km, intensity II · Aguanga 35 km, intensity II · Cathedral City 36 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 310,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 14,000× the energy of this one
3. Magna, Utah 2020 M 5.7 9,800× the energy of this one
4. This earthquake M 3.0 about 1,100 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 1,700 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

1. 6.6 The 1968 Borrego Mountain, California Earthquake · 47 km SE of this epicentre Apr 9, 1968
2. 6.4 The 1954 San Jacinto Fault, California Earthquake · 42 km ESE of this epicentre Mar 19, 1954
3. 6.0 16km WSW of Oasis, CA · 23 km ESE of this epicentre Mar 25, 1937
4. 5.7 Eastern San Diego County, California · 46 km SE of this epicentre Sep 30, 1916
5. 5.5 8km NNE of Ocotillo Wells, CA · 46 km SE of this epicentre Mar 19, 1954

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 33.4598, -116.4883. Map © OpenStreetMap contributors.

Nearby places

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

Aftershocks so far

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

1. 2.1 8km S of Idyllwild, CA 05:23 UTC
2. 2.1 8km S of Idyllwild, CA 05:23 UTC
3. 2.1 8km SSE of Idyllwild, CA 04:22 UTC
4. 2.4 23km NNW of Borrego Springs, CA 23:27 UTC
5. 1.8 14km NNE of Borrego Springs, CA 19:07 UTC
6. 1.6 4km W of Lake Henshaw, CA 12:19 UTC
7. 1.6 15km NNW of Ocotillo Wells, CA 13:45 UTC
8. 1.9 14km WNW of Anza, CA 07:23 UTC
9. 1.9 19km ESE of Anza, CA 18:42 UTC
10. 1.9 10km SSW of Idyllwild, CA 14:52 UTC
11. 1.8 20km ESE of Anza, CA 21:08 UTC
12. 1.9 20km ESE of Anza, CA 05:10 UTC
13. 1.9 14km WNW of Anza, CA 03:39 UTC
14. 1.7 18km NNW of Borrego Springs, CA 00:50 UTC
15. 1.8 22km ESE of Anza, CA 13:49 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 20:16 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.