2.0

M2.0 Earthquake 1km NE of San Ramon, CANovember 17, 2021

2021-11-17 20:16:19 UTC (2021-11-17) · approx. 12:16 PM UTC-8 local

Felt by 19 people across nearby locations.

MagnitudeM2.0(md)
Time20:16 UTC12:16 PM UTC-8
Depth9.3 kmshallow crustal
Coordinates37.790°, -121.968°
Felt by19DYFI responses
Status✓ Reviewed by USGS

On November 17, 2021 at 20:16 UTC, a magnitude 2.0 shallow crustal earthquake struck 1km NE of San Ramon, CA, at a depth of 9.3 km and coordinates 37.7897°, -121.9675°. This earthquake was detected by 68 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 71, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 2.0 releases seismic energy equivalent to roughly 16.7 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 15 m — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in California, a region characterized by the San Andreas transform fault system, where the Pacific and North American plates slide past each other at roughly 46 mm per year. The nearest mapped fault system is the San Andreas Fault. View all earthquakes in California.

Learn more: San Andreas Fault · Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 37.79°, -121.97°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 19 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 M2.0 earthquake near 1km NE of San Ramon, CA

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

Earthquake Details

Magnitude
2.0 md
Depth
9.3 km
shallow crustal
Location
37.7897°N
-121.9675°E
Felt Reports
19
DYFI responses
Community Intensity
4.1
CDI from reports

Technical Information

Event ID
nc73654140
Event Type
earthquake
Status
✓ Reviewed
Significance
71
Stations Used
68
Azimuthal Gap
59.0°
Min Station Distance
0.028°
RMS Residual
0.07 sec
Last Updated
2021-11-18 06:53:11 UTC

Common Questions

How strong was the magnitude 2.0 earthquake near San Ramon, CA?

The magnitude 2.0 earthquake that struck 1km NE of San Ramon, CA on November 17, 2021 at 20:16 UTC had a depth of 9.3 km. For context, this was a minor earthquake typically detected only by instruments.

Where did the earthquake occur?

The earthquake epicenter was located at 37.7897°, -121.9675°, which is 1km NE of San Ramon, CA. View all earthquakes in California.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 2.0 earthquakes can continue for several days and gradually diminish over time.

Has California had earthquakes this big before?

The largest recorded earthquake in California was the M7.9 Fort Tejon earthquake of January 9, 1857. Today's magnitude 2.0 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: nc73654140). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, November 17, 2021). M2.0 Earthquake 1km NE of San Ramon, CANovember 17, 2021. Retrieved November 18, 2021 from https://www.earthquaketracker.org/earthquakes/event/nc73654140/