Magnitude7.4

Reviewed by USGSRussia105y ago

M7.4 earthquake 97 km SSE of Ust’-Kamchatsk Staryy, Russia

Saturday, February 24, 1923, 07:34:44 UTC · 55.461°N, 163.241°E

A magnitude 7.4 earthquake struck 97 km SSE of Ust’-Kamchatsk Staryy, Russia on Saturday, February 24, 1923, 07:34:44 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M8.4 on February 3, 1923.

Magnitude
7.4
Major · mw
Depth
15 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
VI
Strong (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

1.8 megatons of TNT

That is about 118 times the Hiroshima bomb. It released about 3,715 times the energy of a magnitude 5.0.

Tectonic setting

28 km

from the nearest mapped plate boundary, between the Okhotsk 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 22 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 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 21 recorded deaths. The most severe:

  1. 1923M7.2

    Near Kamchatka

    13 Apr 1923 · 124 km away · intensity X

    18 deathsSevere damage ($5–24M)tsunami

  2. 1923M8.4

    Kamchatka

    3 Feb 1923 · 207 km away · intensity XI

    3 deaths$2 million damagetsunami

  3. 1923M7.7

    Kamchatka Peninsula

    24 Feb 1923 · 74 km away

    Limited damage (under $1M)

  4. 1849

    Kamchatka

    28 Sep 1849 · 182 km away

    Limited damage (under $1M)tsunami

  5. 1792M8.4

    Near Kamchatka

    22 Aug 1792 · 181 km away · intensity XI

    tsunami

  6. 1737M7.8

    Off Kamchatka

    4 Nov 1737 · 16 km away · intensity X

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

Nearby trackers

Closest city pages