Earthquake · reviewed by a seismologist
M 4.6mw
Earthquake near Boulder Creek, CA
No earthquake was likely felt in Boulder Creek in the 24 hours to 8:32 pm PST (04:32 UTC). The last one was M 2.3, 12 km (7 mi) E, at 2:58 am PDT on 9 October 2026, estimated intensity II (weak) in town; 3 felt reports to USGS. Every earthquake near Boulder Creek
This page: a magnitude 4.6 earthquake was recorded in Boulder Creek, CA, at 1:41 am PDT on 2 April 2026 (08:41 UTC), 10 km deep. 33,078 people have reported feeling it to USGS.
USGS: 1 km SE of Boulder Creek, CA
33 km (21 mi) SW of San Jose, CA · 17 km (11 mi) NNW of Santa Cruz, CA
- When
- 1:41 am PDT on 2 April 2026 ()
- Where
- in Boulder Creek, CA · earthquakes near Boulder Creek
- Magnitude
- M 4.6 (mw)
- Depth
- 10 km below the surface
- Felt
- 33,078 reports · strongest reported intensity VI
- Measured shaking
- intensity VI (ShakeMap)
- USGS impact alert
- green
- Nearest
- Santa Cruz County, 15 km SE
- Nearest mapped fault
- Zayante-Vergeles fault, 2 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 49 days ago
Earthquake alerts for Boulder Creek, CA
Get a notification in this browser when USGS records an earthquake near Boulder Creek, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.
At this magnitude and depth, people at rest would likely notice it out to about 148 km (92 mi) from the epicentre. 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: Boulder Creek in town, intensity IV · Scotts Valley 11 km, intensity IV · Santa Cruz 17 km, intensity IV · Los Gatos 17 km, intensity IV · Saratoga 18 km, intensity IV · Live Oak 19 km, intensity IV · Capitola 21 km, intensity IV · Campbell 24 km, intensity III. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 120 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.6 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 1,500× the energy of this one
- Mineral, Virginia 2011 M 5.8 65× the energy of this one
- Magna, Utah 2020 M 5.7 46× the energy of this one
- This earthquake M 4.6 about 120 tons of TNT
- Around the size people start to feel M 3.0 this one released 240× more
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 5.1 on 2022-10-25 — about 5.1 times the energy of this one.
Before 2016, the USGS record lists 25 earthquakes of M5 or more within 50 km; the five largest:
- 6.9 The 1989 Loma Prieta, California Earthquake · 22 km ESE of this epicentre
- 6.5 Near Morgan Hill, California · 42 km E of this epicentre
- 6.3 22 km S of Davenport, California · 35 km SSW of this epicentre
- 6.3 16 km SW of Davenport, California · 29 km SW of this epicentre
- 6.2 Near San Jose, California · 34 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 37.1157, -122.1125. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Santa Cruz County, CA | 15 km (9 mi) | SE | earthquakes near Santa Cruz County |
| Santa Clara County, CA | 39 km (24 mi) | ENE | earthquakes near Santa Clara County |
| San Mateo County, CA | 40 km (25 mi) | NW | earthquakes near San Mateo County |
| Alameda County, CA | 62 km (38 mi) | NNE | earthquakes near Alameda County |
| Contra Costa County, CA | 91 km (56 mi) | N | earthquakes near Contra Costa County |
| San Francisco County, CA | 106 km (66 mi) | NW | earthquakes near San Francisco County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
45 earthquakes have been recorded within 50 km since this one.
- 1.8 7 km WSW of Gilroy, CA
- 1.5 3 km ESE of Woodside, CA
- 1.8 3 km NNE of Portola Valley, CA
- 1.7 6 km SSE of Portola Valley, CA
- 1.9 3 km NNE of Portola Valley, CA
- 1.8 15 km E of Seven Trees, CA
- 2.1 9 km ENE of Morgan Hill, CA
- 1.7 4 km ESE of Interlaken, CA
- 1.6 2 km ENE of Aromas, CA
- 2.1 15 km N of Morgan Hill, CA
- 2.2 8 km NE of Alum Rock, CA
- 1.6 2 km ENE of Aromas, CA
- 2.3 14 km N of Morgan Hill, CA
- 1.6 2 km W of Portola Valley, CA
- 1.6 7 km WSW of Gilroy, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.