QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Escondido, CA

No earthquake was likely felt in Escondido in the 24 hours to 8:30 am PST (16:30 UTC). The last one was M 3.6, 51 km (32 mi) NE, at 12:31 am PDT on 19 August 2026, estimated intensity II (weak) in town; 165 felt reports to USGS. Every earthquake near Escondido

This page: a magnitude 1.7 earthquake was recorded 33 km (21 mi) northeast of Escondido, CA, at 1:00 pm PDT on 15 May 2021 (20:00 UTC), 8.1 km deep.

USGS: 2km SE of Palomar Observatory, CA

64 km (40 mi) NNE of San Diego, CA · 31 km (19 mi) ESE of Temecula, CA

1:00 pm PDT, May 15, 2021 · · 8.1 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N San Diego County 36 kmRiverside County 90 kmOrange County 93 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
1:00 pm PDT on 15 May 2021 ()
Where
33 km (21 mi) northeast of Escondido, CA · earthquakes near Escondido
Magnitude
M 1.7 (ml)
Depth
8.1 km below the surface
Felt
no reports yet
Nearest
San Diego County, 36 km S
Nearest mapped fault
Elsinore 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 2004 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 9 km (6 mi) from the epicentre. In Escondido, 33 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: Aguanga, Valley Center, Hidden Meadows, Rainbow, Anza.

How big was it?

This earthquake released about 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 970,000× the energy of this one
  3. Around the size people start to feel M 3.0 86× the energy of this one
  4. This earthquake M 1.7 about 11 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 170,000 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1918 San Jacinto, California Earthquake · 48 km NNW of this epicentre
  2. 5.5 1km ENE of Borrego Springs, CA · 47 km ESE of this epicentre
  3. 5.4 20km NNW of Borrego Springs, CA · 36 km ENE of this epicentre
  4. 5.3 6km SSE of Hemet, CA · 41 km N of this epicentre
  5. 5.3 18km ESE of Anza, CA · 36 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 33.3440, -116.8520. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Diego County, CA 36 km (23 mi) S earthquakes near San Diego County
Riverside County, CA 90 km (56 mi) ENE earthquakes near Riverside County
Orange County, CA 93 km (58 mi) WNW earthquakes near Orange County

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

Aftershocks so far

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

  1. 1.7 10km S of Idyllwild, CA
  2. 3.1 2km NW of Hemet, CA
  3. 1.6 11km N of Borrego Springs, CA
  4. 1.8 6km ESE of Palomar Observatory, CA
  5. 1.6 9km S of Idyllwild, CA
  6. 1.5 10km SSW of Idyllwild, CA
  7. 2.0 12km ESE of Anza, CA
  8. 1.9 2km NW of Lake Henshaw, CA
  9. 1.7 6km NNW of Lakeside, CA
  10. 1.9 5km SW of Idyllwild, CA
  11. 1.9 10km SW of Idyllwild, CA
  12. 1.7 15km N of Borrego Springs, CA
  13. 1.6 6km WSW of Aguanga, CA
  14. 1.7 21km ESE of Anza, CA
  15. 1.8 23km 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.