Magnitude7.1

Reviewed by USGSPapua New Guinea81y ago

M7.1 earthquake in New Britain region, Papua New Guinea

Saturday, December 8, 1945, 01:04:10 UTC · 6.063°S, 150.180°E

A magnitude 7.1 earthquake struck in New Britain region, Papua New Guinea on Saturday, December 8, 1945, 01:04:10 UTC, at a depth of 55.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on January 13, 1941.

Magnitude
7.1
Major · mw
Depth
55 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

674 kilotons of TNT

That is about 45 times the Hiroshima bomb. It released about 1,413 times the energy of a magnitude 5.0.

Tectonic setting

84 km

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

Depth: shallow

55 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 M7.5 on December 28, 1945. 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 78 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 14 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 511 recorded deaths. The most severe:

  1. 1937

    Keravia, Rabaul, Kokopo

    28 May 1937 · 300 km away · intensity VIII

    507 deathsLimited damage (under $1M)tsunami

  2. 1941M7.4

    Bismarck Sea

    13 Jan 1941 · 297 km away

    4 deathsModerate damage ($1–5M)tsunami

  3. 1906M8.0

    New Britain

    14 Sep 1906 · 167 km away

    Severe damage ($5–24M)tsunami

  4. 1895M7.3

    W. Solomon Sea

    6 Mar 1895 · 260 km away

    Moderate damage ($1–5M)tsunami

  5. 1899

    Bismrack Sea

    19 Oct 1899 · 269 km away

    Moderate damage ($1–5M)tsunami

  6. 1920M7.7

    New Britain

    2 Feb 1920 · 53 km away

    Limited damage (under $1M)tsunami

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

Nearby trackers

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