2.6

M2.6 Earthquake 8km W of Petrolia, CADecember 20, 2021

2021-12-20 22:09:15 UTC (2021-12-20) · approx. 2:09 PM UTC-8 local

MagnitudeM2.6(md)
Time22:09 UTC2:09 PM UTC-8
Depth31.4 kmshallow crustal
Coordinates40.333°, -124.372°
Felt by2DYFI responses
Status✓ Reviewed by USGS

On December 20, 2021 at 22:09 UTC, a magnitude 2.6 shallow crustal earthquake struck 8km W of Petrolia, CA, at a depth of 31.4 km and coordinates 40.3328°, -124.3723°.

Physical scale: An earthquake of magnitude 2.6 releases seismic energy equivalent to roughly 116 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 37 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 40.33°, -124.37°

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.

USGS DYFI community-reported intensity map for the M2.6 earthquake near 8km W of Petrolia, CA

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

Earthquake Details

Magnitude
2.6 md
Depth
31.4 km
shallow crustal
Location
40.3328°N
-124.3723°E
Felt Reports
2
DYFI responses
Community Intensity
3.1
CDI from reports

Technical Information

Event ID
nc73666526
Event Type
earthquake
Status
✓ Reviewed
Significance
104
Stations Used
24
Azimuthal Gap
218.0°
Min Station Distance
0.050°
RMS Residual
0.15 sec
Last Updated
2022-03-01 16:38:34 UTC

Common Questions

How strong was the magnitude 2.6 earthquake near Petrolia, CA?

The magnitude 2.6 earthquake that struck 8km W of Petrolia, CA on December 20, 2021 at 22:09 UTC had a depth of 31.4 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 2.6 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 2.6 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: nc73666526). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, December 20, 2021). M2.6 Earthquake 8km W of Petrolia, CADecember 20, 2021. Retrieved March 1, 2022 from https://www.earthquaketracker.org/earthquakes/event/nc73666526/