Earthquake · reviewed by a seismologist
M 2.3md
Earthquake near Sonora, CA
No earthquake was likely felt in Sonora in the 24 hours to 7:12 pm PST (03:12 UTC). The last one was M 5.2, 187 km (116 mi) NE, at 1:17 am PDT on 1 May 2026, estimated intensity II (weak) in town; 1,875 felt reports to USGS. Every earthquake near Sonora
This page: a magnitude 2.3 earthquake was recorded 33 km (20 mi) south-southeast of Sonora, CA, at 6:50 am PDT on 26 October 2019 (13:50 UTC), 25 km deep. 3 people have reported feeling it to USGS.
USGS: 14km S of Groveland-Big Oak Flat, CA
51 km (32 mi) NNE of Merced, CA · 148 km (92 mi) ENE of San Jose, CA
- When
- 6:50 am PDT on 26 October 2019 ()
- Where
- 33 km (20 mi) south-southeast of Sonora, CA · earthquakes near Sonora
- Magnitude
- M 2.3 (md)
- Depth
- 25 km below the surface
- Felt
- 3 reports · strongest reported intensity II
- Nearest
- Mariposa County, 32 km ESE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2570 days ago
Earthquake alerts for Sonora, CA
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Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 Sonora, 33 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: Tuolumne City, Soulsbyville.
How big was it?
This earthquake released about 85 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 180,000× the energy of this one
- Magna, Utah 2020 M 5.7 130,000× the energy of this one
- Around the size people start to feel M 3.0 11× the energy of this one
- This earthquake M 2.3 about 85 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 37.7210, -120.2202. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mariposa County, CA | 32 km (20 mi) | ESE | earthquakes near Mariposa County |
| Tuolumne County, CA | 40 km (25 mi) | NE | earthquakes near Tuolumne County |
| Calaveras County, CA | 60 km (37 mi) | NNW | earthquakes near Calaveras County |
| Madera County, CA | 70 km (44 mi) | SE | earthquakes near Madera County |
| Stanislaus County, CA | 71 km (44 mi) | WSW | earthquakes near Stanislaus County |
| Merced County, CA | 73 km (46 mi) | SW | earthquakes near Merced County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
36 earthquakes have been recorded within 50 km since this one.
- 2.1 19km SSW of Mariposa, CA
- 2.0 17km SSW of Bootjack, CA
- 2.5 18km SSW of Mariposa, CA
- 1.5 14km SSW of Mariposa, CA
- 2.1 11km E of Groveland-Big Oak Flat, CA
- 2.1 18km SSW of Mariposa, CA
- 1.9 1km SW of Mariposa, CA
- 1.6 14km SW of Bootjack, CA
- 2.1 12km WNW of Midpines, CA
- 2.1 14km NW of Midpines, CA
- 1.8 13km S of Mariposa, CA
- 2.6 14km S of Mariposa, CA
- 1.6 13km S of Mariposa, CA
- 1.6 19km SSW of Bootjack, CA
- 2.3 16km SSW of Bootjack, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.