Magnitude5.4

Reviewed by USGSVanuatu53y ago

M5.4 earthquake 33 km W of Port-Olry, Vanuatu

Monday, January 28, 1974, 02:01:34 UTC · 15.002°S, 166.767°E

A magnitude 5.4 earthquake struck 33 km W of Port-Olry, Vanuatu on Monday, January 28, 1974, 02:01:34 UTC, at a depth of 26.0 km (shallow). It is the strongest earthquake within 300 km since an M5.6 on January 20, 1974.

Magnitude
5.4
Moderate · mb
Depth
26 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
—
No ShakeMap
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 75 km aftershock search area

In context

How big was it, and why here?

Energy released

2 kilotons of TNT

That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.

Tectonic setting

28 km

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

Depth: shallow

26 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 75 km

USGS lists 2 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.9 on February 8, 1974. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M5.4
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.634 km ENE of Port-Olry, Vanuatu53y ago · 65 km E of this epicenter
  2. 4.955 km NW of Port-Olry, Vanuatu53y ago · 33 km N of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 297 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 16 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1 recorded deaths. The most severe:

  1. 1971M7.1

    Espiritu Santo, Port Vila

    27 Oct 1971 · 72 km away · intensity VII

    1 deathSevere damage ($5–24M)

  2. 1965M7.6

    Vanuatu Islands

    11 Aug 1965 · 100 km away

    Moderate damage ($1–5M)tsunami

  3. 1973M7.5

    Espiritu Santo, Luganille

    28 Dec 1973 · 63 km away · intensity VII

    Moderate damage ($1–5M)

  4. 1910M7.2

    Espiritu Santo

    10 Nov 1910 · 115 km away

    Moderate damage ($1–5M)tsunami

  5. 1973M7.2

    Luganville, Lamap

    29 Dec 1973 · 19 km away · intensity VIII

    Moderate damage ($1–5M)

  6. 1909

    Espiritu Santo

    8 Jul 1909 · 72 km away

    Moderate damage ($1–5M)tsunami

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

Nearby trackers

Closest city pages