QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Mendota, CA

No earthquake was likely felt in Mendota in the 24 hours to 5:32 pm PST (01:32 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 1.8 earthquake was recorded 24 km (15 mi) southwest of Mendota, CA, at 12:12 pm PDT on 31 August 2023 (19:12 UTC), 1.6 km deep.

USGS: 24 km NNE of New Idria, CA

59 km (37 mi) SW of Madera, CA · 132 km (82 mi) SE of San Jose, CA

12:12 pm PDT, Aug 31, 2023 · · 1.6 km deep · released about 15 lb of TNT

Every earthquake near Mendota Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Benito County 44 kmMerced County 65 kmMonterey County 77 kmFresno County 85 kmKings County 93 kmMadera County 100 kmStanislaus County 111 kmSanta Clara 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
12:12 pm PDT on 31 August 2023 ()
Where
24 km (15 mi) southwest of Mendota, CA · earthquakes near Mendota
Magnitude
M 1.8 (md)
Depth
1.6 km below the surface
Felt
no reports yet
Nearest
San Benito County, 44 km W
Nearest mapped fault
Great Valley thrust fault system, 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 1161 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 13 km (8 mi) from the epicentre. In Mendota, 24 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.

Earthquakes near other towns within 30 km: Firebaugh.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 4.0 on 2022-09-01 — about 2,100 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1983 Coalinga, California Earthquake · 50 km SSE of this epicentre
  2. 6.1 Northwest of Huron, California · 13 km S of this epicentre
  3. 5.8 29 km NE of San Lucas, California · 39 km SSW of this epicentre
  4. 5.4 22 km SSW of Three Rocks, California · 34 km SSE of this epicentre
  5. 5.4 11 km NNW of Coalinga, California · 46 km SSE 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 36.6203, -120.5930. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Benito County, CA 44 km (27 mi) W earthquakes near San Benito County
Merced County, CA 65 km (40 mi) N earthquakes near Merced County
Monterey County, CA 77 km (48 mi) WSW earthquakes near Monterey County
Fresno County, CA 85 km (53 mi) E earthquakes near Fresno County
Kings County, CA 93 km (57 mi) SE earthquakes near Kings County
Madera County, CA 100 km (62 mi) NE earthquakes near Madera 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. 2.1 10 km SE of Pinnacles, CA
  2. 2.2 2 km NNE of Pinnacles, CA
  3. 1.5 22 km NE of King City, CA
  4. 2.1 15 km N of New Idria, CA
  5. 1.9 9 km N of Coalinga, CA
  6. 2.4 10 km N of Coalinga, CA
  7. 1.6 13 km SE of Pinnacles, CA
  8. 2.0 13 km SE of Pinnacles, CA
  9. 2.0 13 km SE of Pinnacles, CA
  10. 2.7 13 km SE of Pinnacles, CA
  11. 1.8 13 km SE of Pinnacles, CA
  12. 1.9 12 km SE of Pinnacles, CA
  13. 2.1 13 km SE of Pinnacles, CA
  14. 2.0 13 km SE of Pinnacles, CA
  15. 2.7 12 km 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.