QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Huron, CA

No earthquake was likely felt in Huron in the 24 hours to 4:51 am PST (12:51 UTC). The last one was M 2.2, 10 km (6 mi) SE, at 2:35 am PDT on 16 September 2026, estimated intensity II (weak) in town. Every earthquake near Huron

This page: a magnitude 1.6 earthquake was recorded 13 km (8 mi) southwest of Huron, CA, at 3:11 am PDT on 20 April 2018 (10:11 UTC), 5.7 km deep.

USGS: 13km SW of Huron, CA

83 km (52 mi) SSW of Fresno, CA · 55 km (34 mi) WSW of Hanford, CA

3:11 am PDT, Apr 20, 2018 · · 5.7 km deep · released about 7.3 lb of TNT

10 km30 km60 km120 km N Kings County 35 kmSan Luis Obispo County 84 kmFresno County 87 kmSan Benito County 97 kmMonterey County 101 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
3:11 am PDT on 20 April 2018 ()
Where
13 km (8 mi) southwest of Huron, CA · earthquakes near Huron
Magnitude
M 1.6 (md)
Depth
5.7 km below the surface
Felt
no reports yet
Nearest
Kings County, 35 km E
Nearest mapped fault
Great Valley thrust fault system, 6 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 3121 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 9 km (6 mi) from the epicentre. In Huron, 13 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: Avenal, Coalinga, Kettleman City.

How big was it?

This earthquake released about 7.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.3 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 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.7 The 1983 Coalinga, California Earthquake · 17 km NW of this epicentre
  2. 6.5 1922 Parkfield, California Earthquake · 41 km S of this epicentre
  3. 6.4 1901 Parkfield, California Earthquake · 30 km WSW of this epicentre
  4. 6.0 2004 Parkfield, California Earthquake · 36 km SSW of this epicentre
  5. 5.6 8 km SW of Huron, California · 5 km NE 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 36.1133, -120.2012. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kings County, CA 35 km (22 mi) E earthquakes near Kings County
San Luis Obispo County, CA 84 km (52 mi) SSW earthquakes near San Luis Obispo County
Fresno County, CA 87 km (54 mi) NE earthquakes near Fresno County
San Benito County, CA 97 km (60 mi) NW earthquakes near San Benito County
Monterey County, CA 101 km (63 mi) W earthquakes near Monterey County

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

Aftershocks so far

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

  1. 3.5 1km W of Parkfield, CA
  2. 2.3 9km S of Riverdale, CA
  3. 1.8 14km NE of Coalinga, CA
  4. 1.8 8km ENE of Coalinga, CA
  5. 1.5 7km SSE of Coalinga, CA
  6. 1.9 7km NE of Coalinga, CA
  7. 1.9 7km NE of Coalinga, CA
  8. 1.6 11km SW of Huron, CA
  9. 1.9 12km NW of Parkfield, CA
  10. 1.6 13km N of Coalinga, CA
  11. 1.7 11km ENE of Coalinga, CA
  12. 1.8 10km W of Huron, CA
  13. 1.7 12km ENE of Coalinga, CA
  14. 1.7 12km ENE of Coalinga, CA
  15. 1.9 23km ENE of San Ardo, 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.