Earthquake · reviewed by a seismologist
M 1.5md
Earthquake near Greenfield, CA
No earthquake was likely felt in Greenfield in the 24 hours to 5:42 am PST (13:42 UTC). The last one was M 3.0, 38 km (23 mi) N, at 2:58 pm PDT on 22 October 2026, estimated intensity II (weak) in town. Every earthquake near Greenfield
This page: a magnitude 1.5 earthquake was recorded 44 km (27 mi) southwest of Greenfield, CA, at 12:43 am PST on 4 December 2024 (08:43 UTC), 7.9 km deep.
USGS: 2 km SE of Lopez Point, CA
- When
- 12:43 am PST on 4 December 2024 ()
- Where
- 44 km (27 mi) southwest of Greenfield, CA · earthquakes near Greenfield
- Magnitude
- M 1.5 (md)
- Depth
- 7.9 km below the surface
- Felt
- no reports yet
- Nearest
- Monterey County, 33 km NE
- Nearest mapped fault
- San Gregorio fault, 2 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 697 days ago
Earthquake alerts for Greenfield, CA
Get a notification in this browser when USGS records an earthquake near Greenfield, 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 Greenfield, 44 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 5.4 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 2,800,000× the energy of this one
- Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
- Around the size people start to feel M 3.0 180× the energy of this one
- This earthquake M 1.5 about 5.4 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 2021-10-25 — about 53,000 times the energy of this one.
Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:
- 6.2 28km NW of Cambria, CA · 37 km SSE of this epicentre
- 5.2 25 km NW of San Simeon, California · 26 km SE of this epicentre
- 5.2 22 km NW of San Simeon, California · 29 km SE of this epicentre
- 5.1 3 km W of Soledad, California · 49 km NNE of this epicentre
- 5.0 8 km WSW of San Ardo, California · 49 km E 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 36.0075, -121.5438. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Monterey County, CA | 33 km (21 mi) | NE | earthquakes near Monterey County |
| San Benito County, CA | 79 km (49 mi) | NNE | earthquakes near San Benito County |
| Santa Cruz County, CA | 119 km (74 mi) | NNW | earthquakes near Santa Cruz County |
| San Luis Obispo County, CA | 120 km (75 mi) | SE | earthquakes near San Luis Obispo County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
37 earthquakes have been recorded within 50 km since this one.
- 2.5 17 km SSE of Lopez Point, CA
- 1.6 25 km SSE of Lopez Point, CA
- 1.8 17 km WNW of San Simeon, CA
- 1.8 24 km NNW of San Simeon, CA
- 3.6 22 km NNW of San Simeon, CA
- 2.3 7 km W of San Simeon, CA
- 2.1 24 km NNW of San Simeon, CA
- 2.0 23 km NNW of San Simeon, CA
- 2.2 21 km NNW of San Simeon, CA
- 1.9 33 km SW of Lopez Point, CA
- 2.2 21 km SW of King City, CA
- 2.3 14 km SE of Point Sur, CA
- 2.2 30 km SSW of Lopez Point, CA
- 1.9 20 km NNW of San Simeon, CA
- 1.9 2 km ESE of Lopez Point, 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.