QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near King City, CA

No earthquake was likely felt in King City in the 24 hours to 6:44 pm PST (02:44 UTC). The last one was M 2.5, 14 km (8 mi) E, at 4:39 pm PDT on 29 September 2026, estimated intensity II (weak) in town. Every earthquake near King City

This page: a magnitude 3.1 earthquake was recorded 31 km (19 mi) east of King City, CA, at 10:23 pm PDT on 21 April 2018 (05:23 UTC), 5.3 km deep. 14 people have reported feeling it to USGS.

USGS: 23km NNE of San Ardo, CA

10:23 pm PDT, Apr 21, 2018 · · 5.3 km deep · released about 1,400 lb of TNT

Every earthquake near King City Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Monterey County 48 kmSan Benito County 54 kmKings County 88 kmSan Luis Obispo County 95 kmMerced County 111 kmFresno 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
10:23 pm PDT on 21 April 2018 ()
Where
31 km (19 mi) east of King City, CA · earthquakes near King City
Magnitude
M 3.1 (ml)
Depth
5.3 km below the surface
Felt
14 reports · strongest reported intensity IV
Nearest
Monterey County, 48 km W
Nearest mapped fault
San Andreas fault, under 1 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 3041 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 42 km (26 mi) from the epicentre. In King City, 31 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: King City 31 km, intensity II · Coalinga 38 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 240,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,700× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× more

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 20 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1983 Coalinga, California Earthquake · 42 km E of this epicentre
  2. 6.4 1901 Parkfield, California Earthquake · 33 km SE of this epicentre
  3. 6.1 Northwest of Huron, California · 37 km NNE of this epicentre
  4. 5.8 29 km NE of San Lucas, California · 11 km N of this epicentre
  5. 5.8 1934 Parkfield, California Earthquake · 40 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 36.1972, -120.7790. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Monterey County, CA 48 km (30 mi) W earthquakes near Monterey County
San Benito County, CA 54 km (33 mi) NNW earthquakes near San Benito County
Kings County, CA 88 km (54 mi) E earthquakes near Kings County
San Luis Obispo County, CA 95 km (59 mi) SSE earthquakes near San Luis Obispo County
Merced County, CA 111 km (69 mi) N earthquakes near Merced County
Fresno County, CA 118 km (74 mi) ENE earthquakes near Fresno County

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

Aftershocks so far

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

  1. 1.5 6km E of Pinnacles, CA
  2. 1.9 15km SE of Pinnacles, CA
  3. 1.9 23km WSW of New Idria, CA
  4. 2.1 18km SW of New Idria, CA
  5. 1.5 6km SW of San Ardo, CA
  6. 1.7 12km ENE of Pinnacles, CA
  7. 2.1 8km WNW of New Idria, CA
  8. 1.6 9km E of Coalinga, CA
  9. 2.6 7km NE of Coalinga, CA
  10. 2.4 21km NW of Parkfield, CA
  11. 1.8 14km ESE of Pinnacles, CA
  12. 2.1 3km SE of San Ardo, CA
  13. 1.8 6km SW of San Ardo, CA
  14. 2.4 15km WSW of Cantua Creek, CA
  15. 1.6 16km 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.