QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Gustine, CA

No earthquake was likely felt in Gustine in the 24 hours to 7:15 pm PST (03:15 UTC). The last one was M 3.1, 23 km (14 mi) WSW, at 9:18 pm PDT on 21 October 2026, estimated intensity II (weak) in town; 9 felt reports to USGS. Every earthquake near Gustine

This page: a magnitude 1.6 earthquake was recorded 23 km (15 mi) southwest of Gustine, CA, at 4:53 am PST on 30 December 2023 (12:53 UTC), 1.5 km deep.

USGS: 24 km SW of Gustine, CA

60 km (37 mi) ESE of San Jose, CA · 37 km (23 mi) ENE of Gilroy, CA

4:53 am PST, Dec 30, 2023 · · 1.5 km deep · released about 7.1 lb of TNT

Every earthquake near Gustine Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Merced County 42 kmSanta Clara County 47 kmStanislaus County 53 kmSan Benito County 56 kmSanta Cruz County 74 kmAlameda County 88 kmSan Joaquin County 92 kmMonterey County 97 kmSan Mateo County 110 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
4:53 am PST on 30 December 2023 ()
Where
23 km (15 mi) southwest of Gustine, CA · earthquakes near Gustine
Magnitude
M 1.6 (md)
Depth
1.5 km below the surface
Felt
no reports yet
Nearest
Merced County, 42 km ENE
Nearest mapped fault
Ortigalita fault, 4 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 1045 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 11 km (7 mi) from the epicentre. In Gustine, 23 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: Newman.

How big was it?

This earthquake released about 7.1 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 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.1 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 5.1 on 2022-10-25 — about 170,000 times the energy of this one.

Before 2016, the USGS record lists 19 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 Near Morgan Hill, California · 40 km W of this epicentre
  2. 6.2 The 1984 Morgan Hill, California Earthquake · 49 km WNW of this epicentre
  3. 5.9 10 km SE of Tres Pinos, California · 42 km S of this epicentre
  4. 5.8 Near Watsonville, California · 49 km WSW of this epicentre
  5. 5.8 Near Paicines, California · 49 km S 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 37.1073, -121.1847. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Merced County, CA 42 km (26 mi) ENE earthquakes near Merced County
Santa Clara County, CA 47 km (29 mi) WNW earthquakes near Santa Clara County
Stanislaus County, CA 53 km (33 mi) NNE earthquakes near Stanislaus County
San Benito County, CA 56 km (35 mi) S earthquakes near San Benito County
Santa Cruz County, CA 74 km (46 mi) W earthquakes near Santa Cruz County
Alameda County, CA 88 km (55 mi) NW earthquakes near Alameda County

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

Aftershocks so far

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

  1. 2.4 8 km SSW of Ridgemark, CA
  2. 2.9 4 km W of San Juan Bautista, CA
  3. 1.6 10 km E of San Martin, CA
  4. 2.4 16 km E of Seven Trees, CA
  5. 2.1 12 km S of Tres Pinos, CA
  6. 1.8 2 km E of Aromas, CA
  7. 2.2 4 km N of San Juan Bautista, CA
  8. 1.6 2 km N of Aromas, CA
  9. 1.8 1 km N of Aromas, CA
  10. 1.6 2 km E of Aromas, CA
  11. 1.9 9 km ENE of San Martin, CA
  12. 1.6 10 km NNW of Hollister, CA
  13. 1.8 12 km S of Tres Pinos, CA
  14. 1.6 6 km SSW of Gilroy, CA
  15. 1.6 3 km WSW of San Juan Bautista, 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.