Magnitude4.3

Reviewed by USGSVanuatu18y ago

M4.3 earthquake 72 km NNE of Isangel, Vanuatu

Saturday, June 21, 2008, 01:01:54 UTC · 18.905°S, 169.425°E

A magnitude 4.3 earthquake struck 72 km NNE of Isangel, Vanuatu on Saturday, June 21, 2008, 01:01:54 UTC, at a depth of 265.7 km (intermediate).

Magnitude
4.3
Light · mb
Depth
266 km
Intermediate
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: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

43 tons of TNT

That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.

Tectonic setting

176 km

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

Depth: intermediate

266 km

Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.

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 50 km

USGS lists 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.9 on July 5, 2008. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M4.3
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.951 km NNW of Isangel, Vanuatu18y ago · 45 km SW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,116 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 29 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 · 156 km away

    26 deathsSevere damage ($5–24M)tsunami

  2. 1920M8.1

    Loyalty Islands

    20 Sep 1920 · 156 km away

    Limited damage (under $1M)tsunami

  3. 1878M7.5

    Tanna Island

    10 Jan 1878 · 98 km away

    Limited damage (under $1M)tsunami

  4. 1961M7.3

    Vanuatu Islands

    23 Jul 1961 · 120 km away · intensity VI

    Limited damage (under $1M)tsunami

  5. 2002M7.2

    Efate, Port Vila

    2 Jan 2002 · 220 km away

    Limited damage (under $1M)tsunami

  6. 1933M6.4

    Malekula

    19 Nov 1933 · 284 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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