QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

10km ENE of Porterville, CA

· 7.6 km deep · released about 1,600 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Tulare County 19 kmKings County 82 kmKern County 84 kmFresno 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
Magnitude
M 3.1 (ml)
Depth
7.6 km below the surface
Felt
87 reports · strongest reported intensity III
Nearest
Tulare County, 19 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1271 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 87 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,600 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 210,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,700× the energy of this one
  4. This earthquake M 3.1 about 1,600 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.7× 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.

Where

Epicentre 36.0842, -118.9037. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Tulare County, CA 19 km (12 mi) SW of here earthquakes near Tulare County
Kings County, CA 82 km (51 mi) E of here earthquakes near Kings County
Kern County, CA 84 km (52 mi) N of here earthquakes near Kern County
Fresno County, CA 101 km (63 mi) SE of here earthquakes near Fresno County

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

Aftershocks so far

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

  1. 1.9 10 km E of Porterville, CA
  2. 2.4 42 km WSW of Olancha, CA
  3. 2.0 23 km SSE of Porterville, CA
  4. 1.5 23 km SSE of Porterville, CA
  5. 2.2 24 km SSE of Porterville, CA
  6. 1.7 10 km E of Porterville, CA
  7. 2.1 40 km WSW of Olancha, CA
  8. 2.1 8 km WNW of Kernville, CA
  9. 2.0 42 km WSW of Olancha, CA
  10. 2.6 42 km WSW of Olancha, CA
  11. 1.5 42 km WSW of Olancha, CA
  12. 2.0 42 km WSW of Olancha, CA
  13. 3.2 42 km WSW of Olancha, CA
  14. 1.7 42 km WSW of Olancha, CA
  15. 1.9 28 km N of Kernville, 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.