QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Interlaken, CA

No earthquake was likely felt in Interlaken in the 24 hours to 1:36 pm PST (21:36 UTC). The last one was M 2.5, 15 km (9 mi) SE, at 6:10 am PDT on 26 October 2026, estimated intensity II (weak) in town; 6 felt reports to USGS. Every earthquake near Interlaken

This page: a magnitude 1.9 earthquake was recorded 8 km (5 mi) northeast of Interlaken, CA, at 10:59 pm PDT on 2 April 2023 (05:59 UTC), 7.3 km deep. 2 people have reported feeling it to USGS.

USGS: 8km NE of Interlaken, CA

7 km (4 mi) W of Gilroy, CA · 36 km (22 mi) SSE of San Jose, CA

10:59 pm PDT, Apr 2, 2023 · · 7.3 km deep · released about 19 lb of TNT

10 km30 km60 km120 km N Santa Clara County 25 kmSanta Cruz County 30 kmSan Benito County 67 kmAlameda County 76 kmSan Mateo County 78 kmStanislaus County 86 kmMerced County 87 kmMonterey County 90 kmContra Costa 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
10:59 pm PDT on 2 April 2023 ()
Where
8 km (5 mi) northeast of Interlaken, CA · earthquakes near Interlaken
Magnitude
M 1.9 (md)
Depth
7.3 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Santa Clara County, 25 km N
Nearest mapped fault
Sargent 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 1318 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 Interlaken, 8 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: Gilroy 9 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 19 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 810,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 580,000× the energy of this one
  3. Around the size people start to feel M 3.0 51× the energy of this one
  4. This earthquake M 1.9 about 19 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 5.1 on 2022-10-25 — about 63,000 times the energy of this one.

Before 2016, the USGS record lists 33 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 20 km WNW of this epicentre
  2. 6.5 Near Morgan Hill, California · 13 km NNE of this epicentre
  3. 6.2 Near San Jose, California · 36 km NNW of this epicentre
  4. 6.2 The 1984 Morgan Hill, California Earthquake · 35 km N of this epicentre
  5. 6.1 Near San Jose, California · 26 km NNW 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 36.9962, -121.6658. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Clara County, CA 25 km (16 mi) N earthquakes near Santa Clara County
Santa Cruz County, CA 30 km (19 mi) W earthquakes near Santa Cruz County
San Benito County, CA 67 km (42 mi) SE earthquakes near San Benito County
Alameda County, CA 76 km (47 mi) NNW earthquakes near Alameda County
San Mateo County, CA 78 km (48 mi) NW earthquakes near San Mateo County
Stanislaus County, CA 86 km (53 mi) NE earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 2.0 2km N of Hollister, CA
  2. 1.7 11km SSW of Ridgemark, CA
  3. 1.9 14km N of Morgan Hill, CA
  4. 1.6 11km SSW of Tres Pinos, CA
  5. 1.6 2km E of Aromas, CA
  6. 1.5 2km WSW of San Juan Bautista, CA
  7. 2.0 14km ENE of Seven Trees, CA
  8. 1.6 16km E of Seven Trees, CA
  9. 1.7 12km ESE of Alum Rock, CA
  10. 1.6 2km E of Aromas, CA
  11. 3.1 4km S of San Juan Bautista, CA
  12. 2.0 5km NE of Alum Rock, CA
  13. 1.7 5km SSE of San Juan Bautista, CA
  14. 1.6 9km NNE of San Juan Bautista, CA
  15. 1.6 8km 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

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