Magnitude4.7

Reviewed by USGSRussia53y ago

M4.7 earthquake 41 km S of Shikotan, Russia

Tuesday, October 2, 1973, 19:28:09 UTC · 43.424°N, 146.694°E

A magnitude 4.7 earthquake struck 41 km S of Shikotan, Russia on Tuesday, October 2, 1973, 19:28:09 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M5.0 on October 2, 1973.

Magnitude
4.7
Light · mb
Depth
33 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
—
No ShakeMap
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

169 tons of TNT

That is about 1/89 of the Hiroshima bomb. A magnitude 5.0 releases about 3 times more energy.

Tectonic setting

96 km

from the nearest mapped plate boundary, between the Okhotsk and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

33 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 50 km

USGS lists 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.3 on October 9, 1973. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M4.7
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 5.357 km SSE of Shikotan, Russia53y ago · 22 km SE of this epicenter
  2. 5.043 km S of Shikotan, Russia53y ago · 3 km SE of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 462 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 32 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 107 recorded deaths. The most severe:

  1. 1843M8.4

    Hokkaido: Yezo, Kushiro, Nemuro

    25 Apr 1843 · 168 km away

    45 deathsModerate damage ($1–5M)tsunami

  2. 1952M8.1

    Hokkaido

    4 Mar 1952 · 272 km away · intensity IX

    33 deathsSevere damage ($5–24M)tsunami

  3. 1973M7.7

    Hokkaido Island

    17 Jun 1973 · 77 km away · intensity VIII

    27 deaths$5 million damagetsunami

  4. 1894M7.9

    Off Coast Of Honshu

    22 Mar 1894 · 117 km away · intensity IX

    1 deathModerate damage ($1–5M)tsunami

  5. 1938M6.1

    E. Hokkaido Island, Japan

    28 May 1938 · 194 km away

    1 deathLimited damage (under $1M)tsunami

  6. 1958M8.3

    Kuril Islands

    6 Nov 1958 · 192 km away · intensity X

    Moderate damage ($1–5M)tsunami

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

Nearby trackers

Closest city pages