Magnitude7.3

Reviewed by USGSNew Caledonia23y ago

M7.3 earthquake 201 km ESE of Tadine, New Caledonia

Saturday, December 27, 2003, 16:00:59 UTC · 22.015°S, 169.766°E

A magnitude 7.3 earthquake struck 201 km ESE of Tadine, New Caledonia on Saturday, December 27, 2003, 16:00:59 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M7.5 on January 4, 1998.

Magnitude
7.3
Major · mwc
Depth
10 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

1.3 megatons of TNT

That is about 89 times the Hiroshima bomb. It released about 2,818 times the energy of a magnitude 5.0.

Tectonic setting

21 km

from the nearest mapped plate boundary, between the New Hebrides and Australian 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 lists 183 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M7.1 on January 3, 2004. 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 838 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 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 26 recorded deaths. The most severe:

  1. 1875M8.1

    Loyalty Islands: Lifou Island

    28 Mar 1875 · 260 km away

    26 deathsSevere damage ($5–24M)tsunami

  2. 1901M7.9

    Loyalty Islands

    9 Aug 1901 · 24 km away

    Moderate damage ($1–5M)tsunami

  3. 1920M8.1

    Loyalty Islands

    20 Sep 1920 · 263 km away

    Limited damage (under $1M)tsunami

  4. 1913M8.1

    Vanuatu Islands

    14 Oct 1913 · 291 km away

  5. 1995M7.7

    Noumea; Vanuatu: Port-Vila

    16 May 1995 · 111 km away · intensity III

    tsunami

  6. 1910M7.5

    Vanuatu Islands

    1 Jun 1910 · 238 km away

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

Nearby trackers

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