QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

8km N of Day Valley, CA

· 0.5 km deep · released about 6.6 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 16 kmSanta Clara County 21 kmSan Mateo County 56 kmAlameda County 60 kmSan Benito County 89 kmContra Costa County 90 kmStanislaus County 92 kmMerced County 103 kmSan Joaquin County 106 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 1.6 (md)
Depth
0.5 km below the surface
Felt
no reports yet
Nearest
Santa Cruz County, 16 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2631 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 6.6 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 2,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.6 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 37.1087, -121.8755. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Cruz County, CA 16 km (10 mi) NE of here earthquakes near Santa Cruz County
Santa Clara County, CA 21 km (13 mi) SW of here earthquakes near Santa Clara County
San Mateo County, CA 56 km (35 mi) SE of here earthquakes near San Mateo County
Alameda County, CA 60 km (37 mi) S of here earthquakes near Alameda County
San Benito County, CA 89 km (56 mi) NW of here earthquakes near San Benito County
Contra Costa County, CA 90 km (56 mi) S of here earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 2.5 6km SSW of Gilroy, CA
  2. 2.6 19km NE of Morgan Hill, CA
  3. 2.9 19km NE of Morgan Hill, CA
  4. 1.6 3km E of Morgan Hill, CA
  5. 1.9 11km N of Morgan Hill, CA
  6. 3.3 8km ENE of Alum Rock, CA
  7. 1.7 11km ESE of Gilroy, CA
  8. 1.9 8km ENE of San Martin, CA
  9. 2.1 20km NE of Morgan Hill, CA
  10. 1.6 19km NE of Morgan Hill, CA
  11. 2.0 9km ENE of Milpitas, CA
  12. 2.5 3km SW of San Juan Bautista, CA
  13. 1.7 3km E of Aromas, CA
  14. 2.4 3km WSW of San Juan Bautista, CA
  15. 1.5 3km S of Loyola, 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 4.1 on 2017-10-10 — it released about 6,200 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.