Magnitude6.9

Reviewed by USGSFiji47y ago

M6.9 earthquake 78 km ESE of Labasa, Fiji

Friday, November 16, 1979, 15:21:25 UTC · 16.760°S, 179.984°W

A magnitude 6.9 earthquake struck 78 km ESE of Labasa, Fiji on Friday, November 16, 1979, 15:21:25 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M7.0 on January 19, 1967.

Magnitude
6.9
Strong · ms
Depth
33 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 earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

338 kilotons of TNT

That is about 22 times the Hiroshima bomb. It released about 708 times the energy of a magnitude 5.0.

Tectonic setting

123 km

from the nearest mapped plate boundary, between the Balmoral Reef and Australian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: shallow

33 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 100 km

USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M4.3 on November 25, 1979. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M6.9
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.391 km SE of Labasa, Fiji47y ago · 30 km S of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 221 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 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 8 recorded deaths. The most severe:

  1. 1953M6.4

    Fiji Islands

    14 Sep 1953 · 258 km away

    8 deathsLimited damage (under $1M)tsunami

  2. 1919M6.9

    Rabi,Tunuloa Mission,Suvasavu

    3 Oct 1919 · 40 km away · intensity VIII

    Moderate damage ($1–5M)

  3. 1979M6.9

    Fiji Islands

    16 Nov 1979 · 0 km away

    Moderate damage ($1–5M)tsunami

  4. 1932M6.4

    Koro,Mudu,Suvasavu

    8 Mar 1932 · 162 km away · intensity VII

    Moderate damage ($1–5M)

  5. 1884

    Macuata

    Jan 1884 · 137 km away · intensity VII

    Limited damage (under $1M)tsunami

  6. 1909M7.8

    Fiji Islands

    22 Feb 1909 · 173 km away

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

Nearby trackers

Closest city pages