QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

Earthquake near Porterville, CA

USGS: 12km E of Porterville, CA

13 km (8 mi) E of Porterville, CA · 80 km (50 mi) N of Bakersfield, CA

3:12 pm PST, Feb 28, 2017 · · 11 km deep · released about 52 lb of TNT

Every earthquake near Porterville Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Tulare County 21 kmKern County 81 kmKings County 83 kmFresno County 104 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
3:12 pm PST on 28 February 2017 ()
Where
12 km (7 mi) E of Porterville, CA · earthquakes near Porterville
Magnitude
M 2.2 (ml)
Depth
11 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Tulare County, 21 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3426 days ago

A magnitude 2.2 earthquake was recorded 12 km (7 mi) E of Porterville, CA, at 3:12 pm PST on 28 February 2017 (23:12 UTC). 2 people have reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: East Porterville, Terra Bella, Strathmore, Poplar-Cotton Center, Lindsay, Woodville.

How big was it?

This earthquake released about 52 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 290,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 200,000× the energy of this one
  3. Around the size people start to feel M 3.0 18× the energy of this one
  4. This earthquake M 2.2 about 52 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 one earthquake of M5 or more within 50 km:

  1. 5.0 5 km S of Springville, California · 6 km ENE 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 36.0622, -118.8877. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Tulare County, CA 21 km (13 mi) NNE earthquakes near Tulare County
Kern County, CA 81 km (50 mi) S earthquakes near Kern County
Kings County, CA 83 km (52 mi) W earthquakes near Kings County
Fresno County, CA 104 km (64 mi) NW earthquakes near Fresno County

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

Aftershocks so far

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

  1. 1.5 8km NNW of Kernville, CA
  2. 1.7 13km SE of Woodlake, CA
  3. 1.7 32km NNE of Kernville, CA
  4. 1.9 8km NNW of Kernville, CA
  5. 2.1 6km W of Kernville, CA
  6. 1.7 10km WNW of Pixley, CA
  7. 2.0 16km WNW of Kernville, CA
  8. 1.8 8km NNE of Porterville, CA
  9. 1.6 10km NNW of Kernville, CA
  10. 1.8 28km NNE of Kernville, CA
  11. 1.8 28km NNE of Kernville, CA
  12. 1.6 5km W of Kernville, CA
  13. 1.7 5km WNW of Kernville, CA
  14. 2.7 32km ESE of Porterville, CA
  15. 1.6 32km NNE 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.