QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Fort Irwin, CA

No earthquake was likely felt in Fort Irwin in the 24 hours to 7:35 am PST (15:35 UTC). The last one was M 4.3, 103 km (64 mi) W, at 9:40 am PDT on 13 July 2026, estimated intensity II (weak) in town; 1,090 felt reports to USGS. Every earthquake near Fort Irwin

This page: a magnitude 2.7 earthquake was recorded 35 km (22 mi) northwest of Fort Irwin, CA, at 6:17 am PST on 4 February 2018 (14:17 UTC), 6.1 km deep. 2 people have reported feeling it to USGS.

USGS: 35km NW of Fort Irwin, CA

6:17 am PST, Feb 4, 2018 · · 6.1 km deep · released about 340 lb of TNT

Every earthquake near Fort Irwin Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Bernardino County 99 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
6:17 am PST on 4 February 2018 ()
Where
35 km (22 mi) northwest of Fort Irwin, CA · earthquakes near Fort Irwin
Magnitude
M 2.7 (ml)
Depth
6.1 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
San Bernardino County, 99 km SE
Nearest mapped fault
Garlock fault, 15 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 1558 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 24 km (15 mi) from the epicentre. In Fort Irwin, 35 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.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 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 4.1 on 2017-08-22 — about 130 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 35.4812, -116.9607. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Bernardino County, CA 99 km (62 mi) SE earthquakes near San Bernardino County

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

Aftershocks so far

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

  1. 4.0 11km SSW of Searles Valley, CA
  2. 3.6 9km SSW of Searles Valley, CA
  3. 2.3 40km ESE of Trona, CA
  4. 2.0 31km WSW of Tecopa, CA
  5. 2.1 36km W of Tecopa, CA
  6. 1.8 31km WSW of Tecopa, CA
  7. 1.6 30km SW of Tecopa, CA
  8. 2.3 29km SW of Tecopa, CA
  9. 2.3 37km NNW of Fort Irwin, CA
  10. 2.0 37km NNW of Fort Irwin, CA
  11. 2.4 18km ESE of Ridgecrest, CA
  12. 1.6 37km WSW of Tecopa, CA
  13. 2.2 34km WSW of Tecopa, CA
  14. 1.5 49km WSW of Shoshone, CA
  15. 2.4 41km E of Johannesburg, 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.