Magnitude7.2

Reviewed by USGSJapan104y ago

M7.2 earthquake 64 km ENE of Hasaki, Japan

Friday, June 1, 1923, 17:24:46 UTC · 35.936°N, 141.501°E

A magnitude 7.2 earthquake struck 64 km ENE of Hasaki, Japan on Friday, June 1, 1923, 17:24:46 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on September 7, 1906.

Magnitude
7.2
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 earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

1.0 megatons of TNT

That is about 68 times the Hiroshima bomb. It released about 2,138 times the energy of a magnitude 5.0.

Tectonic setting

88 km

from the nearest mapped plate boundary, between the Pacific and Okhotsk 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 lists 2 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.7 on June 1, 1923. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M7.2
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 6.4164 km E of Hasaki, Japan104y ago · 104 km E of this epicenter
  2. 6.760 km ENE of Hasaki, Japan104y ago · 6 km SW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 27 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 23 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 118,978 recorded deaths. The most severe:

  1. 1923M7.9

    Tokyo, Yokohama

    1 Sep 1923 · 204 km away

    105,385 deaths$600 million damagetsunami

  2. 1855M7.0

    Tokyo

    11 Nov 1855 · 157 km away

    6,757 deathsExtreme damage ($25M+)tsunami

  3. 1703M8.2

    Off Sw Boso Peninsula

    30 Dec 1703 · 171 km away

    5,233 deathsExtreme damage ($25M+)tsunami

  4. 1828

    Sandyo In Etigo

    18 Dec 1828 · 249 km away

    1,443 deathsExtreme damage ($25M+)tsunami

  5. 1853

    Odawara

    11 Mar 1853 · 187 km away

    79 deathsSevere damage ($5–24M)

  6. 1905M7.0

    Off Fukushima

    6 Jul 1905 · 190 km away

    57 deathstsunami

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

Nearby trackers

Closest city pages