QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Gustine, CA

No earthquake was likely felt in Gustine in the 24 hours to 3:48 am PST (11:48 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 2.1 earthquake was recorded 20 km (12 mi) southwest of Gustine, CA, at 5:38 pm PDT on 11 September 2020 (00:38 UTC), 4.8 km deep. 1 person has reported feeling it to USGS.

USGS: 20km SW of Gustine, CA

64 km (40 mi) ESE of San Jose, CA · 42 km (26 mi) ENE of Gilroy, CA

5:38 pm PDT, Sep 11, 2020 · · 4.8 km deep · released about 47 lb of TNT

10 km30 km60 km120 km N Merced County 37 kmStanislaus County 51 kmSanta Clara County 51 kmSan Benito County 56 kmSanta Cruz County 79 kmAlameda County 91 kmSan Joaquin County 92 kmMonterey County 99 kmSan Mateo County 115 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
5:38 pm PDT on 11 September 2020 ()
Where
20 km (12 mi) southwest of Gustine, CA · earthquakes near Gustine
Magnitude
M 2.1 (md)
Depth
4.8 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Merced County, 37 km ENE
Nearest mapped fault
Ortigalita 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 2242 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 17 km (11 mi) from the epicentre. In Gustine, 20 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, Los Banos.

How big was it?

This earthquake released about 47 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 320,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 20× the energy of this one
  4. This earthquake M 2.1 about 47 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 lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 Near Morgan Hill, California · 45 km W of this epicentre
  2. 5.9 10 km SE of Tres Pinos, California · 43 km SSW of this epicentre
  3. 5.8 The 1979 Coyote Lake, California Earthquake · 34 km W of this epicentre
  4. 5.5 7 km SW of Hollister, California · 45 km SW of this epicentre
  5. 5.5 3 km ENE of Tres Pinos, California · 37 km SSW 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 37.1130, -121.1262. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Merced County, CA 37 km (23 mi) ENE earthquakes near Merced County
Stanislaus County, CA 51 km (32 mi) NNE earthquakes near Stanislaus County
Santa Clara County, CA 51 km (32 mi) WNW earthquakes near Santa Clara County
San Benito County, CA 56 km (35 mi) S earthquakes near San Benito County
Santa Cruz County, CA 79 km (49 mi) W earthquakes near Santa Cruz County
Alameda County, CA 91 km (57 mi) NW earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.8 4km S of San Juan Bautista, CA
  2. 1.6 3km E of Aromas, CA
  3. 1.8 6km WSW of Gilroy, CA
  4. 1.7 7km WSW of Gilroy, CA
  5. 2.8 6km SSE of San Juan Bautista, CA
  6. 1.8 4km SSE of San Juan Bautista, CA
  7. 3.0 5km S of San Juan Bautista, CA
  8. 3.3 4km S of San Juan Bautista, CA
  9. 2.1 4km S of San Juan Bautista, CA
  10. 1.6 30km NE of Pinnacles, CA
  11. 2.1 32km NE of Pinnacles, CA
  12. 1.7 8km SSW of Tres Pinos, CA
  13. 1.7 3km E of Aromas, CA
  14. 1.6 7km S of Gilroy, CA
  15. 2.1 6km SE of Tres Pinos, 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.