2.1

M2.1 Earthquake 5 km ENE of Vallejo, CAMay 9, 2025

2025-05-09 17:35:58 UTC (2025-05-09) · approx. 9:35 AM UTC-8 local

MagnitudeM2.1(md)
Time17:35 UTC9:35 AM UTC-8
Depth-0.1 kmshallow crustal
Coordinates38.133°, -122.181°
Felt by6DYFI responses
Status✓ Reviewed by USGS

On May 9, 2025 at 17:35 UTC, a magnitude 2.1 shallow crustal earthquake struck 5 km ENE of Vallejo, CA, at a depth of -0.1 km and coordinates 38.1327°, -122.1807°.

Physical scale: An earthquake of magnitude 2.1 releases seismic energy equivalent to roughly 23.6 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 18 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 38.13°, -122.18°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 6 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M2.1 earthquake near 5 km ENE of Vallejo, CA

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
2.1 md
Depth
-0.1 km
shallow crustal
Location
38.1327°N
-122.1807°E
Felt Reports
6
DYFI responses
Community Intensity
3.4
CDI from reports

Technical Information

Event ID
nc75178991
Event Type
quarry blast
Status
✓ Reviewed
Significance
72
Stations Used
12
Azimuthal Gap
121.0°
Min Station Distance
0.027°
RMS Residual
0.21 sec
Last Updated
2025-06-09 05:00:25 UTC

Common Questions

How strong was the magnitude 2.1 earthquake near Vallejo, CA?

The magnitude 2.1 earthquake that struck 5 km ENE of Vallejo, CA on May 9, 2025 at 17:35 UTC had a depth of -0.1 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 2.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 2.1 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: nc75178991). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, May 9, 2025). M2.1 Earthquake 5 km ENE of Vallejo, CAMay 9, 2025. Retrieved June 9, 2025 from https://www.earthquaketracker.org/earthquakes/event/nc75178991/