Magnitude7.2

Reviewed by USGSJapan92y ago

M7.2 earthquake 192 km ENE of Miyako, Japan

Friday, October 18, 1935, 00:11:59 UTC · 40.232°N, 144.060°E

A magnitude 7.2 earthquake struck 192 km ENE of Miyako, Japan on Friday, October 18, 1935, 00:11:59 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.3 on June 18, 1933.

Magnitude
7.2
Major · mw
Depth
15 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
IV
Light (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

919 kilotons of TNT

That is about 61 times the Hiroshima bomb. It released about 1,928 times the energy of a magnitude 5.0.

Tectonic setting

23 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 3 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M6.5 on October 18, 1935. 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. 5.4197 km ENE of Miyako, Japan92y ago · 18 km SE of this epicenter
  2. 5.7172 km ENE of Miyako, Japan92y ago · 35 km NW of this epicenter
  3. 6.5185 km ENE of Miyako, Japan92y ago · 10 km NW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 152 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 36 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 32,885 recorded deaths. The most severe:

  1. 1896M8.3

    Sanriku

    15 Jun 1896 · 82 km away

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

  2. 1933M8.4

    Sanriku

    2 Mar 1933 · 122 km away

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

  3. 1766M6.9

    Hirosaki

    8 Mar 1766 · 293 km away

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

  4. 1793M8.3

    Sanriku,Rikuzen,Rikuchu

    17 Feb 1793 · 193 km away

    745 deathsSevere damage ($5–24M)tsunami

  5. 1896

    Senhoku, Ugo

    31 Aug 1896 · 261 km away

    206 deathsExtreme damage ($25M+)

  6. 1843M8.4

    Hokkaido: Yezo, Kushiro, Nemuro

    25 Apr 1843 · 255 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