Magnitude7.4

Reviewed by USGSCalifornia106y ago

M7.4 earthquake 123 km W of Big Lagoon, California

Tuesday, January 31, 1922, 13:17:31 UTC · 41.189°N, 125.608°W

A magnitude 7.4 earthquake struck 123 km W of Big Lagoon, California on Tuesday, January 31, 1922, 13:17:31 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude
7.4
Major · mw
Depth
15 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
V
Moderate (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

2.0 megatons of TNT

That is about 131 times the Hiroshima bomb. It released about 4,121 times the energy of a magnitude 5.0.

Tectonic setting

40 km

from the nearest mapped plate boundary, between the Juan de Fuca and North American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

15 km

Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.

Did You Feel It?

Where it was felt

No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.

I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.

After the main event

Aftershocks within 200 km

USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 12 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:

  1. 1865

    Fort Humboldt, Eureka

    1 Oct 1865 · 95 km away · intensity IX

    Moderate damage ($1–5M)

  2. 1922M7.6

    Northern

    31 Jan 1922 · 23 km away

    Limited damage (under $1M)

  3. 1873M6.7

    Northern

    23 Nov 1873 · 161 km away · intensity VIII

    Limited damage (under $1M)tsunami

  4. 1871M5.9

    Humboldt County

    2 Mar 1871 · 147 km away · intensity VII

    Limited damage (under $1M)

  5. 1898

    N Coast,Mendocino County

    14 Apr 1898 · 279 km away · intensity X

    Limited damage (under $1M)

  6. 1855

    Northern

    20 Mar 1855 · 128 km away · intensity V

    tsunami

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

Closest city pages