Basic HTML Version
Tsunami hazard in Wallis and Futuna.
enhanced knowede, improved
protection
A study shedding more light on the tsunami hazard on the islands of Wallis and Futuna was recently completed.
A multi- agency effort, the study was facilitated by SPC and led by the NZ National Institute of Water and
Atmospheric Research (NIWA) and the Nouméa -based Institute of Research for Development (IRD), with the
support of EU funding.
Like most Pacific islands, Wallis and Futuna faces the risk of tsunami, two of which hit the island of Futuna in
1993 and 2009. Knowledge of the tsunami hazard remains limited as it requires extensive knowledge of the
seafloor topography and of wave dynamics, particularly in coastal areas.
The study benefited from several research projects undertaken between 2009 and 2012 including: the
investigation of geological evidence of past tsunamis on the islands (with the expertise of the University of
New South Wales); the characterisation of potential tsunamigenic earthquakes around the Pacific region; the
development of numerical models of the generation and propagation of tsunami; and the identification of the
resulting inundation on coastal areas in Wallis and Futuna. This data allowed scientists to generate maps of
tsunami propagation and inundation for a number of tsunami scenarios impacting the islands of Wallis and
Futuna.
Three type of tsunamis were investigated: (1) ocean -wide tsunami generated by earthquake sources such as
Chile or Japan; (2) regional tsunami, where the tsunami arrival is within two hours of its source, such as Tonga
Trench or Vanuatu; and (3) local tsunami, where the source is less than 100 km from the local coast with an
arrival of only a few minutes after the earthquake such as the Futuna Transform.
Based on the research conducted during this study altogether 14 earthquake sources were considered capable
of generating tsunamis large enough to affect Wallis or Futuna.
7193.6 1,, heh.n
ò
Japan
JLu
rl I Trench
+IluiyIn
g
Pçrü
^
[hIrr
T1p N4r#h Tqr,ge
11)
Ih
225)
Tonga Trench
a$,
Centrad Tanga
tk1S
1141,
Futuna Ii4ca111
#
Sauth Vanuatu
#k1
3134.1
Venuüu Oackran
tü
Mk-
Nprkh llirlintu
1NS
ih35
4 Nile pno
.y i.p5p
1
2
Tow from. r.arthrpuaka nu' 'limner f6tcunarnl Ora arrival and rluratlan nt wave activity
%Ufi
MIEürR
s
m
yy
z!
la
Lt
IA
ia
!i
v
II
23
!!
li N
4
5
a
r
TpNAMTp
TugI Trim
Ceire Tor
F.IS
VIrnsatu Sack A