QuakeIndex

Earthquake · automatic estimate, may change

M 1.8md

Earthquake near Bonny Doon, CA

No earthquake was likely felt in Bonny Doon in the 24 hours to 6:30 am PST (14:30 UTC). The last one was M 3.8, 79 km (49 mi) N, at 8:30 am PDT on 13 August 2026, estimated intensity II (weak) in town; 7,876 felt reports to USGS. Every earthquake near Bonny Doon

This page: a magnitude 1.8 earthquake was recorded 13 km (8 mi) west-northwest of Bonny Doon, CA, at 4:17 am PDT on 16 October 2026 (11:17 UTC), 6.1 km deep. The magnitude and location are an automatic first estimate and may change.

USGS: 13 km WNW of Bonny Doon, CA

49 km (30 mi) WSW of San Jose, CA · 26 km (16 mi) WNW of Santa Cruz, CA

4:17 am PDT, Oct 16, 2026 · · 6.1 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 26 kmSan Mateo County 38 kmSanta Clara County 56 kmAlameda County 72 kmSan Francisco County 97 kmContra Costa County 98 kmMarin County 115 kmSan Benito County 119 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
4:17 am PDT on 16 October 2026 ()
Where
13 km (8 mi) west-northwest of Bonny Doon, CA · earthquakes near Bonny Doon
Magnitude
M 1.8 (md)
Depth
6.1 km below the surface
Felt
no reports yet
Nearest
Santa Cruz County, 26 km ESE
Nearest mapped fault
San Gregorio fault, under 1 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 27 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 12 km (7 mi) from the epicentre. In Bonny Doon, 13 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.

Earthquakes near other towns within 30 km: Boulder Creek, Brookdale, Ben Lomond, Felton, Mount Hermon, Lompico.

How big was it?

This earthquake released about 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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 4.6 on 2026-04-02 — about 18,000 times the energy of this one.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 37 km E of this epicentre
  2. 6.3 22 km S of Davenport, California · 31 km SSE of this epicentre
  3. 6.3 16 km SW of Davenport, California · 18 km SSW of this epicentre
  4. 6.1 Near San Jose, California · 46 km ENE of this epicentre
  5. 5.8 7 km NNW of Boulder Creek, California · 18 km NE 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 37.0790, -122.2922. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Cruz County, CA 26 km (16 mi) ESE earthquakes near Santa Cruz County
San Mateo County, CA 38 km (24 mi) N earthquakes near San Mateo County
Santa Clara County, CA 56 km (35 mi) ENE earthquakes near Santa Clara County
Alameda County, CA 72 km (44 mi) NNE earthquakes near Alameda County
San Francisco County, CA 97 km (60 mi) NW earthquakes near San Francisco County
Contra Costa County, CA 98 km (61 mi) NNE earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 2.0 4 km WSW of Cupertino, CA
  2. 1.8 9 km ESE of Lexington Hills, CA
  3. 1.5 2 km WSW of Campbell, CA
  4. 1.0 5 km SSW of Los Altos Hills, 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.