Earthquake · reviewed by a seismologist
M 1.5ml
Earthquake near Alta Sierra, CA
No earthquake was likely felt in Alta Sierra in the 24 hours to 12:32 pm PST (20:32 UTC). The last one was M 3.1, 14 km (9 mi) ESE, at 2:37 am PDT on 6 October 2026, estimated intensity III (weak) in town; 30 felt reports to USGS. Every earthquake near Alta Sierra
This page: a magnitude 1.5 earthquake was recorded 46 km (29 mi) north-northeast of Alta Sierra, CA, at 5:21 am PST on 3 December 2025 (13:21 UTC), 8.8 km deep.
USGS: 42 km WSW of Olancha, CA
54 km (33 mi) E of Porterville, CA · 103 km (64 mi) NNE of Bakersfield, CA
- When
- 5:21 am PST on 3 December 2025 ()
- Where
- 46 km (29 mi) north-northeast of Alta Sierra, CA · earthquakes near Alta Sierra
- Magnitude
- M 1.5 (ml)
- Depth
- 8.8 km below the surface
- Felt
- no reports yet
- Nearest
- Tulare County, 32 km WNW
- Nearest mapped fault
- Kern Canyon 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 344 days ago
Earthquake alerts for Alta Sierra, CA
Get a notification in this browser when USGS records an earthquake near Alta Sierra, CA. No account or email needed.
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, people at rest would likely notice it out to about 6 km (4 mi) from the epicentre. In Alta Sierra, 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.
How big was it?
This earthquake released about 6.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
- Around the size people start to feel M 3.0 150× the energy of this one
- This earthquake M 1.5 about 6.2 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
The largest earthquake within 50 km since 2016 was M 4.2 on 2020-06-04 — about 8,500 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.0 5 km S of Springville, California · 35 km W 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 36.1388, -118.4422. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Tulare County, CA | 32 km (20 mi) | WNW | earthquakes near Tulare County |
| Kern County, CA | 92 km (57 mi) | SSW | earthquakes near Kern County |
| Inyo County, CA | 104 km (65 mi) | ENE | earthquakes near Inyo County |
| Fresno County, CA | 129 km (80 mi) | WNW | earthquakes near Fresno County |
| Madera County, CA | 167 km (104 mi) | NW | earthquakes near Madera County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
45 earthquakes have been recorded within 50 km since this one.
- 1.6 12 km S of Olancha, CA
- 1.9 10 km E of Porterville, CA
- 1.8 13 km SW of Olancha, CA
- 2.4 42 km WSW of Olancha, CA
- 2.2 12 km S of Olancha, CA
- 2.1 28 km WSW of Olancha, CA
- 1.7 10 km E of Porterville, CA
- 1.8 28 km WSW of Olancha, CA
- 1.7 28 km WSW of Olancha, CA
- 2.1 12 km S of Olancha, CA
- 1.6 28 km WSW of Olancha, CA
- 1.8 7 km NE of Coso Junction, CA
- 1.8 28 km WSW of Olancha, CA
- 1.9 28 km WSW of Olancha, CA
- 1.6 12 km S of Olancha, 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.