M4.0 Earthquake 10 km N of Lake Pillsbury, CA — October 28, 2026
2026-10-28 12:01:11 UTC (45 min ago) · approx. 4:01 AM UTC-8 local
On October 28, 2026 at 12:01 UTC, a magnitude 4.0 shallow crustal earthquake struck 10 km N of Lake Pillsbury, CA, at a depth of 10.6 km and coordinates 39.5005°, -122.9518°. The earthquake was reported felt by 2 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.7 (light).
Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 16 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 352 m — a useful intuition for the size of the slip patch on the fault.
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 2 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-122.9518°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.0 earthquake near Lake Pillsbury, CA?
The magnitude 4.0 earthquake that struck 10 km N of Lake Pillsbury, CA on October 28, 2026 at 12:01 UTC had a depth of 10.6 km. It was felt by 2 people with maximum shaking intensity of MMI 3.7 (light). For context, this was a light earthquake commonly felt near the epicenter.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.0 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 4.0 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: nc75458907). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, October 28, 2026). M4.0 Earthquake 10 km N of Lake Pillsbury, CA — October 28, 2026. Retrieved October 28, 2026 from https://www.earthquaketracker.org/earthquakes/event/nc75458907/