QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Modesto, CA

No earthquake was likely felt in Modesto in the 24 hours to 2:47 am PST (10:47 UTC). The last one was M 3.5, 47 km (29 mi) WSW, at 7:21 am PDT on 27 September 2026, estimated intensity II (weak) in town; 8 felt reports to USGS. Every earthquake near Modesto

This page: a magnitude 1.7 earthquake was recorded 21 km (13 mi) west of Modesto, CA, at 3:56 pm PDT on 25 October 2022 (22:56 UTC), 14 km deep.

USGS: 9km NW of Grayson, CA

63 km (39 mi) NE of San Jose, CA · 18 km (11 mi) S of Manteca, CA

3:56 pm PDT, Oct 25, 2022 · · 14 km deep · released about 9.6 lb of TNT

10 km30 km60 km120 km N Stanislaus County 22 kmSan Joaquin County 34 kmAlameda County 59 kmSanta Clara County 60 kmMerced County 67 kmContra Costa County 70 kmCalaveras County 87 kmSacramento County 92 kmSolano County 94 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
3:56 pm PDT on 25 October 2022 ()
Where
21 km (13 mi) west of Modesto, CA · earthquakes near Modesto
Magnitude
M 1.7 (md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Stanislaus County, 22 km ESE
Nearest mapped fault
Great Valley thrust fault system, 10 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 1478 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Modesto, 21 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: Salida, Ripon, Riverdale Park, West Modesto, Manteca, Patterson.

How big was it?

This earthquake released about 9.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 99× the energy of this one
  4. This earthquake M 1.7 about 9.6 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

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

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.7 15 km NE of East Foothills, California · 43 km WSW of this epicentre
  2. 5.4 9 km NE of Livermore, California · 43 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 37.6310, -121.2385. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Stanislaus County, CA 22 km (14 mi) ESE earthquakes near Stanislaus County
San Joaquin County, CA 34 km (21 mi) N earthquakes near San Joaquin County
Alameda County, CA 59 km (37 mi) W earthquakes near Alameda County
Santa Clara County, CA 60 km (38 mi) SW earthquakes near Santa Clara County
Merced County, CA 67 km (41 mi) SE earthquakes near Merced County
Contra Costa County, CA 70 km (44 mi) WNW earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 2.0 22km WSW of Gustine, CA
  2. 2.0 18km SSE of Livermore, CA
  3. 1.6 13km SSE of Livermore, CA
  4. 2.9 19km SSE of Livermore, CA
  5. 1.6 20km NE of Alum Rock, CA
  6. 1.6 18km WSW of Westley, CA
  7. 1.6 3km NW of Byron, 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.