3.6

M3.6 Earthquake 7km NE of Imperial, CAApril 21, 2022

2022-04-21 18:58:50 UTC (2022-04-21) · approx. 10:58 AM UTC-8 local

Felt by 21 people across nearby locations.

MagnitudeM3.6(mw)
Time18:58 UTC10:58 AM UTC-8
Depth9.4 kmshallow crustal
Coordinates32.895°, -115.513°
Felt by21DYFI responses· max MMI 3.7
Status✓ Reviewed by USGS

On April 21, 2022 at 18:58 UTC, a magnitude 3.6 shallow crustal earthquake struck 7km NE of Imperial, CA, at a depth of 9.4 km and coordinates 32.8948°, -115.5135°. The earthquake was reported felt by 21 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.7 (light). This earthquake was detected by 55 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 210, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 3.6 releases seismic energy equivalent to roughly 4.1 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 190 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 32.89°, -115.51°

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.

USGS ShakeMap intensity contours for the M3.6 earthquake near 7km NE of Imperial, CA

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 21 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 M3.6 earthquake near 7km NE of Imperial, CA

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

Earthquake Details

Magnitude
3.6 mw
Depth
9.4 km
shallow crustal
Location
32.8948°N
-115.5135°E
Felt Reports
21
DYFI responses
Intensity (MMI)
3.7
light
Community Intensity
3.8
CDI from reports

Technical Information

Event ID
ci40243288
Event Type
earthquake
Status
✓ Reviewed
Significance
210
Stations Used
55
Azimuthal Gap
39.0°
Min Station Distance
0.040°
RMS Residual
0.30 sec
Last Updated
2023-04-29 21:28:32 UTC

Common Questions

How strong was the magnitude 3.6 earthquake near Imperial, CA?

The magnitude 3.6 earthquake that struck 7km NE of Imperial, CA on April 21, 2022 at 18:58 UTC had a depth of 9.4 km. It was felt by 21 people with maximum shaking intensity of MMI 3.7 (light). For context, this was a minor earthquake typically detected only by instruments.

Where did the earthquake occur?

The earthquake epicenter was located at 32.8948°, -115.5135°, which is 7km NE of Imperial, CA. View all earthquakes in California.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.6 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 3.6 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: ci40243288). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, April 21, 2022). M3.6 Earthquake 7km NE of Imperial, CAApril 21, 2022. Retrieved April 29, 2023 from https://www.earthquaketracker.org/earthquakes/event/ci40243288/