quarry blast · reviewed by a seismologist
M 1.7md
Earthquake near Prunedale, CA
No earthquake was likely felt in Prunedale in the 24 hours to 3:51 am PST (11:51 UTC). The last one was M 2.0, 11 km (7 mi) ENE, at 2:11 am PST on 11 November 2026, estimated intensity II (weak) in town. Every earthquake near Prunedale
No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 1.7 quarry blast was recorded 8 km (5 mi) east-southeast of Prunedale, CA, at 12:43 pm PST on 11 January 2023 (20:43 UTC), less than 1 km deep.
USGS: 8km ESE of Prunedale, CA
8 km (5 mi) NNE of Salinas, CA
- When
- 12:43 pm PST on 11 January 2023 ()
- Where
- 8 km (5 mi) east-southeast of Prunedale, CA · earthquakes near Prunedale
- Magnitude
- M 1.7 (md)
- Depth
- -0.3 km below the surface
- Felt
- no reports yet
- Nearest
- San Benito County, 47 km ESE
- Nearest mapped fault
- Zayante-Vergeles fault, 7 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 1395 days ago
Earthquake alerts for Prunedale, CA
Get a notification in this browser when USGS records an earthquake near Prunedale, 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 12 km (7 mi) from the epicentre. In Prunedale, 8 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.
Likely felt in: Prunedale 8 km, intensity II · Salinas 10 km, intensity II. Estimated for each town centre; each link is that town's own record.
USGS catalogues this as quarry blast, not an earthquake.
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
The largest earthquake within 50 km since 2016 was M 4.7 on 2019-10-15 — about 38,000 times the energy of this one.
Before 2016, the USGS record lists 27 earthquakes of M5 or more within 50 km; the five largest:
- 6.9 The 1989 Loma Prieta, California Earthquake · 41 km NW of this epicentre
- 6.5 Near Morgan Hill, California · 40 km N of this epicentre
- 5.9 10 km SE of Tres Pinos, California · 33 km E of this epicentre
- 5.8 Near Watsonville, California · 24 km NNW of this epicentre
- 5.8 Near Paicines, California · 31 km ESE 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 36.7502, -121.5873. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| San Benito County, CA | 47 km (29 mi) | ESE | earthquakes near San Benito County |
| Santa Cruz County, CA | 47 km (29 mi) | NW | earthquakes near Santa Cruz County |
| Santa Clara County, CA | 53 km (33 mi) | N | earthquakes near Santa Clara County |
| Monterey County, CA | 62 km (38 mi) | SSE | earthquakes near Monterey County |
| Merced County, CA | 91 km (57 mi) | ENE | earthquakes near Merced County |
| San Mateo County, CA | 101 km (63 mi) | NW | earthquakes near San Mateo County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 1.8 8km SW of Ridgemark, CA
- 2.2 14km WNW of Pinnacles, CA
- 2.3 2km ENE of Pinnacles, CA
- 1.6 5km NNW of Aromas, CA
- 2.6 3km SSW of Ridgemark, CA
- 1.5 6km NNW of Aromas, CA
- 2.1 4km NNW of Pinnacles, CA
- 1.8 5km SSE of San Juan Bautista, CA
- 1.9 5km SSE of San Juan Bautista, CA
- 1.5 13km NE of Hollister, CA
- 1.7 16km NW of Pinnacles, CA
- 2.5 9km ENE of San Martin, CA
- 1.8 9km ENE of San Martin, CA
- 1.7 9km ENE of San Martin, CA
- 2.0 9km ENE of San Martin, 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.