2.1

M2.1 Earthquake 4km S of Pittsburg, CADecember 28, 2022

2022-12-28 22:09:16 UTC (2022-12-28) · approx. 2:09 PM UTC-8 local

MagnitudeM2.1(md)
Time22:09 UTC2:09 PM UTC-8
Depth18.5 kmshallow crustal
Coordinates37.987°, -121.889°
Felt by1DYFI response
Status✓ Reviewed by USGS

On December 28, 2022 at 22:09 UTC, a magnitude 2.1 shallow crustal earthquake struck 4km S of Pittsburg, CA, at a depth of 18.5 km and coordinates 37.9873°, -121.8888°.

Physical scale: An earthquake of magnitude 2.1 releases seismic energy equivalent to roughly 19.9 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 16 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 37.99°, -121.89°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 1 citizen response 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 4km S of Pittsburg, CA

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

Earthquake Details

Magnitude
2.1 md
Depth
18.5 km
shallow crustal
Location
37.9873°N
-121.8888°E
Felt Reports
1
DYFI responses
Community Intensity
1.0
CDI from reports

Technical Information

Event ID
nc73826116
Event Type
earthquake
Status
✓ Reviewed
Significance
67
Stations Used
70
Azimuthal Gap
50.0°
Min Station Distance
0.056°
RMS Residual
0.18 sec
Last Updated
2023-01-09 22:55:15 UTC

Common Questions

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

The magnitude 2.1 earthquake that struck 4km S of Pittsburg, CA on December 28, 2022 at 22:09 UTC had a depth of 18.5 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: nc73826116). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, December 28, 2022). M2.1 Earthquake 4km S of Pittsburg, CADecember 28, 2022. Retrieved January 9, 2023 from https://www.earthquaketracker.org/earthquakes/event/nc73826116/