QuakeIndex

quarry blast · reviewed by a seismologist

M 1.6ml

Earthquake near San Diego, CA

No earthquake was likely felt in San Diego in the 24 hours to 2:26 am PST (10:26 UTC). The last one was M 4.7, 152 km (95 mi) E, at 12:10 am PDT on 10 May 2026, estimated intensity II (weak) in town; 203 felt reports to USGS. Every earthquake near San Diego

No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 1.6 quarry blast was recorded 22 km (14 mi) southeast of San Diego, CA, at 1:52 pm PST on 28 November 2018 (21:52 UTC), less than 1 km deep.

USGS: 2km ENE of San Ysidro, CA

8 km (5 mi) S of Chula Vista, CA · 31 km (19 mi) SSE of San Diego, CA

1:52 pm PST, Nov 28, 2018 · · -0.4 km deep · released about 9 lb of TNT

10 km30 km60 km120 km N San Diego County 57 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
1:52 pm PST on 28 November 2018 ()
Where
22 km (14 mi) southeast of San Diego, CA · earthquakes near San Diego
Magnitude
M 1.6 (ml)
Depth
-0.4 km below the surface
Felt
no reports yet
Nearest
San Diego County, 57 km NNE
Nearest mapped fault
Newport-Inglewood-Rose Canyon fault, 11 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 2906 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 12 km (7 mi) from the epicentre. In San Diego, 22 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: Imperial Beach, Chula Vista, Bonita, National City, La Presa, Lemon Grove.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 9 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 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 9 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 32.5578, -117.0210. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Diego County, CA 57 km (35 mi) NNE earthquakes near San Diego County

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

Aftershocks so far

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

  1. 2.9 6km NNW of Lakeside, CA
  2. 1.7 4km NE of San Ysidro, CA
  3. 1.5 1km SE of Jamul, CA
  4. 1.6 7 km ESE of Chula Vista, CA
  5. 1.5 7 km ESE of Chula Vista, CA
  6. 1.5 4km NE of San Ysidro, CA
  7. 1.8 27 km S of Tecate, B.C., MX
  8. 1.5 6km NNW of Lakeside, CA
  9. 1.6 12km N of Tecate, B.C., MX
  10. 1.7 7km ESE of Chula Vista, CA
  11. 1.6 16km WSW of Tecate, B.C., MX
  12. 1.9 6km NNW of Lakeside, CA
  13. 1.7 3km NE of San Ysidro, CA
  14. 2.2 16km SW of La Jolla, CA
  15. 1.8 6km SE of Chula Vista, 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.