Earthquake · reviewed by a seismologist
M 1.7md
Earthquake near Madera, CA
No earthquake was likely felt in Madera in the 24 hours to 3:31 pm PST (23:31 UTC). The last one was M 2.6, 5 km (3 mi) WNW, at 5:14 am PDT on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Madera
This page: a magnitude 1.7 earthquake was recorded 46 km (29 mi) north-northeast of Madera, CA, at 10:41 am PDT on 31 July 2021 (17:41 UTC), 29 km deep.
USGS: 12km S of Bootjack, CA
64 km (40 mi) N of Fresno, CA · 47 km (29 mi) NNE of Madera, CA
- When
- 10:41 am PDT on 31 July 2021 ()
- Where
- 46 km (29 mi) north-northeast of Madera, CA · earthquakes near Madera
- Magnitude
- M 1.7 (md)
- Depth
- 29 km below the surface
- Felt
- no reports yet
- Nearest
- Madera County, 20 km SE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1926 days ago
Earthquake alerts for Madera, 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 Madera, 46 km away, the estimate is intensity I (not felt). 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: Ahwahnee, Mariposa, Coarsegold, Yosemite Lakes, Oakhurst, Midpines.
How big was it?
This earthquake released about 9.3 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.
- Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
- Around the size people start to feel M 3.0 100× the energy of this one
- This earthquake M 1.7 about 9.3 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 37.3527, -119.8782. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Madera County, CA | 20 km (12 mi) | SE | earthquakes near Madera County |
| Mariposa County, CA | 25 km (15 mi) | N | earthquakes near Mariposa County |
| Fresno County, CA | 69 km (43 mi) | SSE | earthquakes near Fresno County |
| Tuolumne County, CA | 75 km (46 mi) | N | earthquakes near Tuolumne County |
| Merced County, CA | 77 km (48 mi) | WSW | earthquakes near Merced County |
| Stanislaus County, CA | 102 km (63 mi) | WNW | earthquakes near Stanislaus County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
32 earthquakes have been recorded within 50 km since this one.
- 2.4 21km SSW of Mariposa, CA
- 1.6 1km WSW of Auberry, CA
- 1.7 21km E of Le Grand, CA
- 1.9 6km ENE of Bonadelle Ranchos-Madera Ranchos, CA
- 2.1 19km SSW of Mariposa, CA
- 1.7 20km SE of Yosemite Valley, CA
- 2.0 7km NE of Bonadelle Ranchos-Madera Ranchos, CA
- 2.0 17km SSW of Bootjack, CA
- 2.0 8km W of North Fork, CA
- 2.2 7km SE of Fairmead, CA
- 2.1 12km WNW of Yosemite Lakes, CA
- 2.1 19km SE of Yosemite Valley, CA
- 2.5 18km SSW of Mariposa, CA
- 1.5 7km NE of Bonadelle Ranchos-Madera Ranchos, CA
- 1.9 4km NE of Fairmead, 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.