QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Los Altos Hills, CA

Yes. A magnitude 1.6 earthquake was recorded 2 km (1 mi) WNW of Los Altos Hills, CA, at 1:30 pm PDT on 29 August 2016 (20:30 UTC), 4.6 km deep.

This was on 29 August 2016. The latest near Los Altos Hills: M 2.5 on 19 September 2026.

USGS: 2 km WNW of Los Altos Hills, California

in Palo Alto, CA · 32 km (20 mi) WNW of San Jose, CA

1:30 pm PDT, Aug 29, 2016 · · 4.6 km deep · released about 6.4 lb of TNT

Every earthquake near Los Altos Hills Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Mateo County 19 kmAlameda County 37 kmSanta Cruz County 43 kmSanta Clara County 45 kmContra Costa County 62 kmSan Francisco County 86 kmMarin County 90 kmSan Joaquin County 99 kmSolano County 100 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
1:30 pm PDT on 29 August 2016 ()
Where
2 km (1 mi) WNW of Los Altos Hills, CA · earthquakes near Los Altos Hills
Magnitude
M 1.6 (md)
Depth
4.6 km below the surface
Felt
no reports yet
Nearest
San Mateo County, 19 km W
Nearest mapped fault
Monte Vista-Shannon fault, under 1 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 3531 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 10 km (6 mi) from the epicentre. In Los Altos Hills, 2 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.

Likely felt in: Los Altos 4 km, intensity II · Stanford 5 km, intensity II · Loyola 6 km, intensity II · Portola Valley 7 km, intensity II · Palo Alto 7 km, intensity II · Mountain View 7 km, intensity II · Menlo Park 8 km, intensity II · East Palo Alto 10 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 6.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.6 about 6.4 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 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 46 km SSE of this epicentre
  2. 6.2 Near San Jose, California · 33 km ESE of this epicentre
  3. 6.2 The 1984 Morgan Hill, California Earthquake · 43 km E of this epicentre
  4. 6.1 Near San Jose, California · 38 km ESE of this epicentre
  5. 5.8 7 km NNW of Boulder Creek, California · 22 km S 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 37.3837, -122.1600. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Mateo County, CA 19 km (12 mi) W earthquakes near San Mateo County
Alameda County, CA 37 km (23 mi) NE earthquakes near Alameda County
Santa Cruz County, CA 43 km (27 mi) SSE earthquakes near Santa Cruz County
Santa Clara County, CA 45 km (28 mi) ESE earthquakes near Santa Clara County
Contra Costa County, CA 62 km (39 mi) NNE earthquakes near Contra Costa County
San Francisco County, CA 86 km (53 mi) WNW earthquakes near San Francisco County

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

Aftershocks so far

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

  1. 2.0 11 km S of Half Moon Bay, California
  2. 1.7 3 km SSE of Portola Valley, California
  3. 2.1 3 km SSE of Portola Valley, California
  4. 2.2 14 km N of Morgan Hill, California
  5. 2.0 3 km S of Loyola, California
  6. 1.6 11 km W of Saratoga, California
  7. 1.7 7 km SSE of Pescadero, California
  8. 1.6 9 km NNE of East Foothills, California
  9. 1.6 3 km S of Loyola, California
  10. 1.8 2 km NE of Pacifica, California
  11. 1.6 11 km NW of Davenport, California
  12. 2.5 11 km NW of Davenport, California
  13. 1.6 2 km S of Loyola, California
  14. 1.7 3 km ENE of Lompico, California
  15. 2.5 16 km E of Seven Trees, California

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.