M2.5 quarry blast 12 km ESE of Interlaken, California, United States
A magnitude 2.5 quarry blast struck 12 km ESE of Interlaken, California, United States at 11:14 local time (18:14 UTC) on 17 Sept 2026, at a depth of 0 km, according to USGS.
revised from M2.6
Data: USGS · updated 2026-09-28 21:54 UTC · reviewed
- Magnitude
- 2.5micro
duration magnitude (md)
revised from 2.6 - Depth
- -0.1 km
- Status
- Reviewed
- Origin time
- 2026-09-17 18:14:22 UTC
- Local: 17 Sept 2026, 11:14:22 (America/Los Angeles)
- Epicentre
- 36.892° N, 121.620° W
Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map
Nearby places
| Place | Distance | Est. shaking |
|---|---|---|
| InterlakenCalifornia, United States · pop. 7,321 | 12 km | IIWeak |
| WatsonvilleCalifornia, United States · pop. 53,628 | 13 km | IIWeak |
| GilroyCalifornia, United States · pop. 53,231 | 14 km | IIWeak |
| HollisterCalifornia, United States · pop. 37,462 | 20 km | INot felt |
| SalinasCalifornia, United States · pop. 157,380 | 24 km | INot felt |
| San JoseCalifornia, United States · pop. 997,368 | 55 km | INot felt |
| OaklandCalifornia, United States · pop. 419,267 | 116 km | INot felt |
| San FranciscoCalifornia, United States · pop. 827,526 | 121 km | INot felt |
Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 10 km.
Every agency's solution
Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS · NC, which has been reviewed by an analyst.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| USGS · NCheadlineNorthern California Seismic System via U.S. Geological Survey | 2.5 mdwas 2.6 | -0.1 km | 36.89° N, 121.62° W | – | Reviewed · 1 revision |
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How big was it?
Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.
It released roughly the energy of 94 kg of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 0 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.
M2.5 releases about 35× the energy of M1.5, and its waves are about 11× taller on a seismogram. Energy: 94 kg of TNT vs 3 kg of TNT.
Each square is the energy of one M1.5. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
7 later earthquakes within 30 km; the largest was M2.6 5 days ago. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M2.5
7 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 100.34 | 1.7 | 8 |
| 110.61 | 1.9 | 1 |
| 141.76 | 2.6 | 6 |
| 144.38 | 1.7 | 12 |
| 167.66 | 1.8 | 10 |
| 210.94 | 1.1 | 9 |
| 270.70 | 1.0 | 6 |
- 2.6Near Hollister, California, United States09-23 16:00
- 1.915 km S of Hollister, California, United States09-22 08:50
- 1.814 km S of Rio Del Mar, California, United States09-24 17:54
- 1.713 km SSW of Hollister, California, United States09-21 22:34
- 1.74 km ESE of Interlaken, California, United States09-23 18:37
- 1.1Near Hollister, California, United States09-26 13:10
- 1.08 km ENE of Gilroy, California, United States09-29 00:56
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Reports on SeismoAtlas
No reports yet.
Event id nc75437317. First recorded here 28 Sept 2026, 17:32:11 UTC. Solutions: USGS · NC (usgs:nc75437317). Cite as: SeismoAtlas, “M2.5 quarry blast 12 km ESE of Interlaken, California, United States”, https://seismoatlas.com/earthquake/nc75437317-m2-5-quarry-blast-12-km-ese-of-interlaken-california-united-states, data from USGS.
JSON: /api/v1/events/nc75437317. SeismoAtlas is not an official warning service.