Magnitude7.3

Reviewed by USGSJapan84y ago

M7.3 earthquake 169 km ENE of Hachinohe, Japan

Sunday, June 13, 1943, 05:11:42 UTC · 41.003°N, 143.396°E

A magnitude 7.3 earthquake struck 169 km ENE of Hachinohe, Japan on Sunday, June 13, 1943, 05:11:42 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M7.4 on October 10, 1939.

Magnitude
7.3
Major · mw
Depth
35 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: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

1.4 megatons of TNT

That is about 92 times the Hiroshima bomb. It released about 2,917 times the energy of a magnitude 5.0.

Tectonic setting

90 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

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 200 km

USGS lists 4 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.7 on June 13, 1943. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 184 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 35 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 32,898 recorded deaths. The most severe:

  1. 1896M8.3

    Sanriku

    15 Jun 1896 · 175 km away

    27,122 deathsExtreme damage ($25M+)tsunami

  2. 1933M8.4

    Sanriku

    2 Mar 1933 · 224 km away

    3,022 deathsExtreme damage ($25M+)tsunami

  3. 1766M6.9

    Hirosaki

    8 Mar 1766 · 227 km away

    1,700 deathsSevere damage ($5–24M)tsunami

  4. 1793M8.3

    Sanriku,Rikuzen,Rikuchu

    17 Feb 1793 · 283 km away

    745 deathsSevere damage ($5–24M)tsunami

  5. 1896

    Senhoku, Ugo

    31 Aug 1896 · 231 km away

    206 deathsExtreme damage ($25M+)

  6. 1843M8.4

    Hokkaido: Yezo, Kushiro, Nemuro

    25 Apr 1843 · 244 km away

    45 deathsModerate damage ($1–5M)tsunami

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

Nearby trackers

Closest city pages