M6.8 earthquake 80 km ESE of Shikotan, Russia

Wednesday, January 28, 1925, 04:05:35 UTC · 43.502°N, 147.627°E

A magnitude 6.8 earthquake struck 80 km ESE of Shikotan, Russia on Wednesday, January 28, 1925, 04:05:35 UTC, at a depth of 30.0 km (shallow). It is the strongest earthquake within 300 km since an M6.9 on December 28, 1924.

Magnitude: 6.8; Strong · mw
Depth: 30 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 earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

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

60 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

30 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 5 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.8 on February 2, 1925. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 18 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:

1843M8.4
Hokkaido: Yezo, Kushiro, Nemuro
25 Apr 1843 · 213 km away
45 deathsModerate damage ($1–5M)tsunami
1894M7.9
Off Coast Of Honshu
22 Mar 1894 · 173 km away · intensity IX
1 deathModerate damage ($1–5M)tsunami
1904M7.6
Hokkaido
18 Mar 1904 · 186 km away · intensity X
Limited damage (under $1M)
1839M7.3
Se. Hokkaido Island, Japan
1 May 1839 · 241 km away
Limited damage (under $1M)tsunami
1900M7.9
Kuril Islands
25 Dec 1900 · 143 km away · intensity IX
1896M7.6
Kuril Islands
18 Nov 1896 · 131 km away · intensity IX

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

Nearby trackers