QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0ml

Earthquake near Mendota, CA

No earthquake was likely felt in Mendota in the 24 hours to 1:27 pm PST (21:27 UTC). The last one was M 3.9, 74 km (46 mi) WSW, at 3:19 am PDT on 11 August 2026, estimated intensity II (weak) in town; 34 felt reports to USGS. Every earthquake near Mendota

This page: a magnitude 3.0 earthquake was recorded 29 km (18 mi) southwest of Mendota, CA, at 6:21 pm PST on 28 February 2018 (02:21 UTC), 15 km deep. 60 people have reported feeling it to USGS.

USGS: 17km NNE of New Idria, CA

75 km (46 mi) WSW of Fresno, CA

6:21 pm PST, Feb 28, 2018 · · 15 km deep · released about 890 lb of TNT

10 km30 km60 km120 km N San Benito County 45 kmMerced County 72 kmMonterey County 74 kmFresno County 86 kmKings County 87 kmMadera County 104 kmStanislaus County 118 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
6:21 pm PST on 28 February 2018 ()
Where
29 km (18 mi) southwest of Mendota, CA · earthquakes near Mendota
Magnitude
M 3.0 (ml)
Depth
15 km below the surface
Felt
60 reports · strongest reported intensity III
Nearest
San Benito County, 45 km W
Nearest mapped fault
Great Valley thrust fault system, 3 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 3092 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 32 km (20 mi) from the epicentre. In Mendota, 29 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: Mendota 29 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 890 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 380,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 17,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 12,000× the energy of this one
  4. This earthquake M 3.0 about 890 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1983 Coalinga, California Earthquake · 43 km SE of this epicentre
  2. 6.1 Northwest of Huron, California · 6 km SSW of this epicentre
  3. 5.8 29 km NE of San Lucas, California · 33 km SSW of this epicentre
  4. 5.5 11 km NNE of Coalinga, California · 45 km SE of this epicentre
  5. 5.5 11 km NE of Coalinga, California · 46 km SE 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 36.5542, -120.5825. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Benito County, CA 45 km (28 mi) W earthquakes near San Benito County
Merced County, CA 72 km (45 mi) N earthquakes near Merced County
Monterey County, CA 74 km (46 mi) WSW earthquakes near Monterey County
Fresno County, CA 86 km (53 mi) ENE earthquakes near Fresno County
Kings County, CA 87 km (54 mi) SE earthquakes near Kings County
Madera County, CA 104 km (65 mi) NE earthquakes near Madera County

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

Aftershocks so far

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

  1. 2.3 13km SE of Pinnacles, CA
  2. 1.6 8km NE of Coalinga, CA
  3. 3.0 23km NNE of San Ardo, CA
  4. 1.7 8km ESE of Pinnacles, CA
  5. 1.7 7km NNE of Pinnacles, CA
  6. 2.3 11km SE of Pinnacles, CA
  7. 2.2 20km SW of New Idria, CA
  8. 1.5 24km ENE of San Lucas, CA
  9. 1.5 11km ESE of Pinnacles, CA
  10. 1.6 22km NNE of San Ardo, CA
  11. 3.1 23km NNE of San Ardo, CA
  12. 1.8 10km SE of Pinnacles, CA
  13. 2.2 14km NNW of Coalinga, CA
  14. 2.0 3km NNE of Pinnacles, CA
  15. 2.4 23km SE of Pinnacles, 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.