QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

4km ESE of Aromas, CA

· 5.4 km deep · released about 550 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Cruz County 39 kmSanta Clara County 40 kmSan Benito County 54 kmMonterey County 75 kmMerced County 86 kmAlameda County 91 kmSan Mateo County 91 kmStanislaus County 93 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 2.8 (md)
Depth
5.4 km below the surface
Felt
45 reports · strongest reported intensity IV
Nearest
Santa Cruz County, 39 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3102 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 45 people have reported feeling it to USGS.

How big was it?

This earthquake released about 550 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 28,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 19,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.7× the energy of this one
  4. This earthquake M 2.8 about 550 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.

Where

Epicentre 36.8705, -121.6023. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 39 km (24 mi) ESE of here earthquakes near Santa Cruz County
Santa Clara County, CA 40 km (25 mi) S of here earthquakes near Santa Clara County
San Benito County, CA 54 km (34 mi) WNW of here earthquakes near San Benito County
Monterey County, CA 75 km (46 mi) NNW of here earthquakes near Monterey County
Merced County, CA 86 km (53 mi) WSW of here earthquakes near Merced County
Alameda County, CA 91 km (56 mi) SSE of here earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.7 16km NW of Pinnacles, CA
  2. 2.9 17km SSE of Tres Pinos, CA
  3. 2.8 16km SSE of Tres Pinos, CA
  4. 1.7 5km SW of Gilroy, CA
  5. 2.6 5km WNW of San Juan Bautista, CA
  6. 2.3 5km WNW of San Juan Bautista, CA
  7. 2.8 5km WNW of San Juan Bautista, CA
  8. 3.0 5km WNW of San Juan Bautista, CA
  9. 2.0 9km NE of Gilroy, CA
  10. 2.6 9km NE of Gilroy, CA
  11. 2.5 7km WSW of Gilroy, CA
  12. 2.0 8km WSW of Gilroy, CA
  13. 1.6 2km E of Aromas, CA
  14. 2.3 15km ESE of Tres Pinos, CA
  15. 1.8 11km NNW of Hollister, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.6 on 2017-11-13 — it released about 410 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.