quarry blast · reviewed by a seismologist
M 0.7ml
Earthquake near Winchester, CA
No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 0.7 quarry blast was recorded 4 km (3 mi) SW of Winchester, CA, at 1:03 pm PDT on 12 October 2026 (20:03 UTC), less than 1 km deep. No felt reports to USGS yet.
USGS: 4 km SW of Winchester, CA
6 km (4 mi) E of Menifee, CA · 125 km (78 mi) ESE of Los Angeles, CA
- When
- 1:03 pm PDT on 12 October 2026 ()
- Where
- 4 km (3 mi) SW of Winchester, CA · earthquakes near Winchester
- Magnitude
- M 0.7 (ml)
- Depth
- -0.6 km below the surface
- Felt
- no reports yet
- Nearest
- Orange County, 61 km W
- Nearest mapped fault
- Elsinore fault, 16 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 13 hours 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. 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: Menifee, Homeland, Green Acres, Nuevo, Canyon Lake, Perris.
USGS catalogues this as quarry blast, not an earthquake.
How big was it?
This earthquake released about 0.29 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 1.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 51,000,000× the energy of this one
- Magna, Utah 2020 M 5.7 36,000,000× the energy of this one
- Around the size people start to feel M 3.0 3,200× the energy of this one
- This earthquake M 0.7 about 0.29 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 4.5 on 2018-05-08 — about 560,000 times the energy of this one.
Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:
- 6.7 The 1918 San Jacinto, California Earthquake · 16 km ENE of this epicentre
- 6.2 3 km SE of San Bernardino, California · 47 km NNW of this epicentre
- 6.0 The 1910 Lake Elsinore, California Earthquake · 26 km W of this epicentre
- 5.3 6km SSE of Hemet, CA · 17 km E of this epicentre
- 5.2 8km ENE of Trabuco Canyon, CA · 36 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 33.6813, -117.1197. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Orange County, CA | 61 km (38 mi) | W | earthquakes near Orange County |
| San Diego County, CA | 80 km (50 mi) | SSE | earthquakes near San Diego County |
| Riverside County, CA | 104 km (64 mi) | E | earthquakes near Riverside County |
| Los Angeles County, CA | 120 km (75 mi) | WNW | earthquakes near Los Angeles County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
4 earthquakes have been recorded within 50 km since this one.
- 0.5 7 km SSW of Idyllwild, CA
- 0.8 8 km NNW of Cabazon, CA
- 0.9 9 km WNW of Anza, CA
- 0.4 8 km SW of Anza, 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.