QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Greenfield, CA

No earthquake was likely felt in Greenfield in the 24 hours to 9:49 pm PST (05:49 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 1.7 earthquake was recorded 47 km (29 mi) east-northeast of Greenfield, CA, at 12:45 pm PDT on 12 April 2024 (19:45 UTC), 7.0 km deep.

USGS: 11 km NW of New Idria, CA

12:45 pm PDT, Apr 12, 2024 · · 7.0 km deep · released about 9.6 lb of TNT

10 km30 km60 km120 km N San Benito County 32 kmMonterey County 56 kmMerced County 79 kmKings County 97 kmFresno County 104 kmSanta Clara County 116 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
12:45 pm PDT on 12 April 2024 ()
Where
47 km (29 mi) east-northeast of Greenfield, CA · earthquakes near Greenfield
Magnitude
M 1.7 (md)
Depth
7.0 km below the surface
Felt
no reports yet
Nearest
San Benito County, 32 km WNW
Nearest mapped fault
Great Valley thrust fault system, 20 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 938 days ago

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 10 km (6 mi) from the epicentre. In Greenfield, 47 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 9.6 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.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 99× the energy of this one
  4. This earthquake M 1.7 about 9.6 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 36,000 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1983 Coalinga, California Earthquake · 50 km SE of this epicentre
  2. 6.1 Northwest of Huron, California · 15 km E of this epicentre
  3. 5.9 10 km SE of Tres Pinos, California · 49 km NW of this epicentre
  4. 5.8 Near Paicines, California · 48 km WNW of this epicentre
  5. 5.8 29 km NE of San Lucas, California · 21 km S 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 36.4867, -120.7665. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Benito County, CA 32 km (20 mi) WNW earthquakes near San Benito County
Monterey County, CA 56 km (35 mi) WSW earthquakes near Monterey County
Merced County, CA 79 km (49 mi) N earthquakes near Merced County
Kings County, CA 97 km (60 mi) ESE earthquakes near Kings County
Fresno County, CA 104 km (64 mi) ENE earthquakes near Fresno County
Santa Clara County, CA 116 km (72 mi) NW earthquakes near Santa Clara County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

54 earthquakes have been recorded within 50 km since this one.

  1. 1.7 10 km E of Pinnacles, CA
  2. 1.9 15 km NNW of Pinnacles, CA
  3. 1.9 16 km NW of Pinnacles, CA
  4. 2.3 16 km NNW of Pinnacles, CA
  5. 2.1 15 km NNW of Pinnacles, CA
  6. 2.9 15 km S of Tres Pinos, CA
  7. 2.7 15 km NNW of Pinnacles, CA
  8. 1.8 22 km NE of San Ardo, CA
  9. 1.8 3 km ENE of Pinnacles, CA
  10. 2.7 8 km E of Pinnacles, CA
  11. 1.5 13 km NNW of Pinnacles, CA
  12. 1.8 7 km E of Pinnacles, CA
  13. 2.0 23 km ENE of San Ardo, CA
  14. 2.2 18 km SW of Cantua Creek, CA
  15. 1.8 19 km ESE of Tres Pinos, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.