Magnitude7.0

Reviewed by USGSTurkey84y ago

M7.0 earthquake 13 km SE of Ayvacık, Turkey

Sunday, December 20, 1942, 14:03:09 UTC · 40.907°N, 36.744°E

A magnitude 7.0 earthquake struck 13 km SE of Ayvacık, Turkey on Sunday, December 20, 1942, 14:03:09 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M7.8 on December 26, 1939.

Magnitude
7.0
Major · mw
Depth
10 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
VII
Very strong (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

477 kilotons of TNT

That is about 32 times the Hiroshima bomb. It released about 1,000 times the energy of a magnitude 5.0.

Tectonic setting

23 km

from the nearest mapped plate boundary, between the Anatolian and Eurasian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

10 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 has not published any M2.5+ earthquake within 200 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 45 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 21 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 39,577 recorded deaths. The most severe:

  1. 1939M7.8

    Erzincan

    26 Dec 1939 · 265 km away · intensity XII

    32,700 deaths$20 million damagetsunami

  2. 1784

    Erzurum,Erzincan

    23 Jul 1784 · 269 km away

    5,000 deathsSevere damage ($5–24M)

  3. 1942M7.0

    Niksar, Erbaa

    20 Dec 1942 · 0 km away · intensity X

    1,000 deathsExtreme damage ($25M+)

  4. 1835

    Turkey

    23 Aug 1835 · 288 km away · intensity X

    300 deathsModerate damage ($1–5M)

  5. 1938M6.6

    Kirsehir

    19 Apr 1938 · 284 km away · intensity X

    224 deathsSevere damage ($5–24M)

  6. 1844

    Osmancik, Ankara

    12 May 1844 · 163 km away · intensity IX

    200 deathsSevere damage ($5–24M)

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

Nearby trackers

Closest city pages