Magnitude6.8

Reviewed by USGSRussia103y ago

M6.8 earthquake 125 km ESE of Shikotan, Russia

Monday, February 2, 1925, 19:46:53 UTC · 43.544°N, 148.232°E

A magnitude 6.8 earthquake struck 125 km ESE of Shikotan, Russia on Monday, February 2, 1925, 19:46:53 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on January 28, 1925.

Magnitude
6.8
Strong · mw
Depth
35 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: 100 km aftershock search area

In context

How big was it, and why here?

Energy released

265 kilotons of TNT

That is about 18 times the Hiroshima bomb. It released about 556 times the energy of a magnitude 5.0.

Tectonic setting

35 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

35 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 100 km

USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.2 on February 2, 1925. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M6.8
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 6.2136 km SE of Shikotan, Russia103y ago · 84 km SW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 25 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 46 recorded deaths. The most severe:

  1. 1843M8.4

    Hokkaido: Yezo, Kushiro, Nemuro

    25 Apr 1843 · 250 km away

    45 deathsModerate damage ($1–5M)tsunami

  2. 1894M7.9

    Off Coast Of Honshu

    22 Mar 1894 · 215 km away · intensity IX

    1 deathModerate damage ($1–5M)tsunami

  3. 1904M7.6

    Hokkaido

    18 Mar 1904 · 229 km away · intensity X

    Limited damage (under $1M)

  4. 1839M7.3

    Se. Hokkaido Island, Japan

    1 May 1839 · 287 km away

    Limited damage (under $1M)tsunami

  5. 1900M7.9

    Kuril Islands

    25 Dec 1900 · 191 km away · intensity IX

  6. 1918M7.8

    Kuril Islands

    8 Nov 1918 · 282 km away

    tsunami

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

Nearby trackers

Closest city pages