QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Modesto, CA

USGS: 2 km NW of Diablo Grande, California

48 km (30 mi) ENE of San Jose, CA · 36 km (22 mi) SW of Modesto, CA

9:55 pm PDT, Jul 1, 2016 · · -0.7 km deep · released about 23 lb of TNT

Every earthquake near Modesto Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Stanislaus County 31 kmSanta Clara County 41 kmMerced County 56 kmSan Joaquin County 58 kmAlameda County 61 kmSanta Cruz County 77 kmContra Costa County 81 kmSan Benito County 91 kmSan Mateo County 95 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
9:55 pm PDT on 1 July 2016 ()
Where
36 km (23 mi) SW of Modesto, CA · earthquakes near Modesto
Magnitude
M 1.9 (md)
Depth
-0.7 km below the surface
Felt
no reports yet
Nearest
Stanislaus County, 31 km ENE
Nearest mapped fault
Great Valley thrust fault system, 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 3521 days ago

A magnitude 1.9 earthquake was recorded 36 km (23 mi) SW of Modesto, CA, at 9:55 pm PDT on 1 July 2016 (04:55 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Patterson, Newman.

How big was it?

This earthquake released about 23 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 660,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 470,000× the energy of this one
  3. Around the size people start to feel M 3.0 42× the energy of this one
  4. This earthquake M 1.9 about 23 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 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 Near Morgan Hill, California · 45 km SW of this epicentre
  2. 6.2 Near San Jose, California · 47 km WSW of this epicentre
  3. 6.2 The 1984 Morgan Hill, California Earthquake · 36 km WSW of this epicentre
  4. 5.8 The 1979 Coyote Lake, California Earthquake · 39 km SSW of this epicentre
  5. 5.7 15 km NE of East Foothills, California · 36 km WNW 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 37.4122, -121.2928. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Stanislaus County, CA 31 km (19 mi) ENE earthquakes near Stanislaus County
Santa Clara County, CA 41 km (25 mi) WSW earthquakes near Santa Clara County
Merced County, CA 56 km (35 mi) ESE earthquakes near Merced County
San Joaquin County, CA 58 km (36 mi) N earthquakes near San Joaquin County
Alameda County, CA 61 km (38 mi) WNW earthquakes near Alameda County
Santa Cruz County, CA 77 km (48 mi) SW earthquakes near Santa Cruz County

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

Aftershocks so far

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

  1. 2.3 7 km NNE of East Foothills, California
  2. 1.9 10 km N of East Foothills, California
  3. 1.6 10 km NNE of East Foothills, California
  4. 1.7 14 km E of Seven Trees, California
  5. 1.9 14 km E of Seven Trees, California
  6. 2.2 14 km N of Morgan Hill, California
  7. 1.6 9 km NNE of East Foothills, California
  8. 2.5 16 km E of Seven Trees, California
  9. 2.3 16 km E of Seven Trees, California
  10. 2.4 8 km NNE of East Foothills, California
  11. 1.7 13 km ENE of East Foothills, California
  12. 1.8 11 km ESE of East Foothills, California
  13. 1.5 11 km ESE of East Foothills, California
  14. 3.3 11 km ESE of East Foothills, California
  15. 2.1 11 km ESE of East Foothills, California

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.