QuakeIndex

Earthquake · reviewed by a seismologist

M 3.7mw

Earthquake near Anza, CA

No earthquake was likely felt in Anza in the 24 hours to 5:59 am PST (13:59 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 3.7 earthquake was recorded 16 km (10 mi) east-southeast of Anza, CA, at 7:05 pm PDT on 3 April 2020 (02:05 UTC), 10 km deep. 486 people have reported feeling it to USGS.

USGS: 16km ESE of Anza, CA

95 km (59 mi) NE of San Diego, CA · 30 km (19 mi) SSW of Palm Desert, CA

7:05 pm PDT, Apr 3, 2020 · · 10 km deep · released about 4.7 tons of TNT

Every earthquake near Anza Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Riverside County 54 kmSan Diego County 58 kmOrange County 119 kmImperial County 119 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
7:05 pm PDT on 3 April 2020 ()
Where
16 km (10 mi) east-southeast of Anza, CA · earthquakes near Anza
Magnitude
M 3.7 (mw)
Depth
10 km below the surface
Felt
486 reports · strongest reported intensity V
Measured shaking
intensity IV (ShakeMap)
Nearest
Riverside County, 54 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 1412 days ago

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 72 km (45 mi) from the epicentre. In Anza, 16 km away, the estimate is intensity III (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 16 km, intensity III · La Quinta 27 km, intensity III · Palm Desert 28 km, intensity III · Borrego Springs 30 km, intensity III · Cathedral City 32 km, intensity II · Aguanga 33 km, intensity II · Idyllwild 33 km, intensity II · Indio 37 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 4.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 36,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,100× the energy of this one
  4. This earthquake M 3.7 about 4.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 9.8× more

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 200 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 The 1954 San Jacinto Fault, California Earthquake · 46 km ESE of this epicentre
  2. 6.0 16km WSW of Oasis, CA · 27 km ESE of this epicentre
  3. 5.5 1km ENE of Borrego Springs, CA · 30 km SSE of this epicentre
  4. 5.4 20km NNW of Borrego Springs, CA · 9 km SSE of this epicentre
  5. 5.3 6km SSE of Hemet, CA · 46 km WNW 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 33.4947, -116.5153. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Riverside County, CA 54 km (34 mi) ENE earthquakes near Riverside County
San Diego County, CA 58 km (36 mi) SSW earthquakes near San Diego County
Orange County, CA 119 km (74 mi) W earthquakes near Orange County
Imperial County, CA 119 km (74 mi) ESE earthquakes near Imperial County

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. 2.0 15km ESE of Anza, CA
  2. 2.8 16km ESE of Anza, CA
  3. 1.8 15km ESE of Anza, CA
  4. 1.7 15km ESE of Anza, CA
  5. 1.7 16km ESE of Anza, CA
  6. 1.5 16km ESE of Anza, CA
  7. 1.7 16km ESE of Anza, CA
  8. 1.8 15km ESE of Anza, CA
  9. 1.9 16km ESE of Anza, CA
  10. 2.0 17km ESE of Anza, CA
  11. 2.3 16km ESE of Anza, CA
  12. 1.8 17km ESE of Anza, CA
  13. 1.9 15km ESE of Anza, CA
  14. 1.7 16km ESE of Anza, CA
  15. 1.5 16km ESE 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.