QuakeIndex

Earthquake · reviewed by a seismologist

M 1.1ml

Earthquake near Borrego Springs, CA

USGS: 11 km SSW of Borrego Springs, CA

77 km (48 mi) ENE of San Diego, CA

9:04 pm PDT, Oct 1, 2026 · · 8.0 km deep · released about 1.6 lb of TNT

10 km30 km60 km120 km N San Diego County 37 kmRiverside County 74 kmImperial County 100 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
9:04 pm PDT on 1 October 2026 ()
Where
11 km (7 mi) SSW of Borrego Springs, CA · earthquakes near Borrego Springs
Magnitude
M 1.1 (ml)
Depth
8.0 km below the surface
Felt
no reports yet
Nearest
San Diego County, 37 km WSW
Nearest mapped fault
Elsinore fault, 8 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 22 hours ago

A magnitude 1.1 earthquake was recorded 11 km (7 mi) SSW of Borrego Springs, CA, at 9:04 pm PDT on 1 October 2026 (04:04 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Julian.

How big was it?

This earthquake released about 1.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 9,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 6,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 600× the energy of this one
  4. This earthquake M 1.1 about 1.6 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 2025-04-14 — about 1,200,000 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. 6.6 The 1968 Borrego Mountain, California Earthquake · 30 km E of this epicentre
  2. 6.4 The 1954 San Jacinto Fault, California Earthquake · 35 km ENE of this epicentre
  3. 6.0 16km WSW of Oasis, CA · 30 km NNE of this epicentre
  4. 5.7 Eastern San Diego County, California · 30 km E of this epicentre
  5. 5.5 8km NNE of Ocotillo Wells, CA · 30 km E 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 33.1675, -116.4198. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Diego County, CA 37 km (23 mi) WSW earthquakes near San Diego County
Riverside County, CA 74 km (46 mi) NNE earthquakes near Riverside County
Imperial County, CA 100 km (62 mi) E earthquakes near Imperial County

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

Aftershocks so far

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

  1. 0.4 4 km E of Anza, CA
  2. 0.3 15 km N of Warner Springs, CA
  3. 0.8 21 km ESE of Anza, CA
  4. 0.3 15 km N of Warner Springs, CA
  5. 0.9 22 km ESE of Anza, CA
  6. 0.7 22 km ESE of Anza, CA
  7. 0.6 21 km ESE of Anza, CA
  8. 0.6 22 km ESE of Anza, CA
  9. 2.0 22 km ESE of Anza, CA
  10. 0.4 18 km ESE of Anza, CA
  11. 0.3 14 km N of Warner Springs, CA
  12. 1.0 11 km SSW of Borrego Springs, CA
  13. 0.7 24 km NE of Pine 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.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
review statusautomaticreviewed
longitude-116.42-116.42
latitude33.1733.17
depth7.757.98
longitude-116.43-116.42
latitude33.1733.17
depth7.77.75
magnitude1.341.15

On USGS

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