@article{fdi:010086960,
  title = {{P}otential tsunami hazard of the southern {V}anuatu subduction zone : tectonics, case study of the {M}atthew {I}sland tsunami of 10 {F}ebruary 2021 and implication in regional hazard assessment},
  author = {{R}oger, {J}. and {P}elletier, {B}ernard and {G}usman, {A}. and {P}ower, {W}. and {W}ang, {X}. {M}. and {B}urbidge, {D}. and {D}uphil, {M}axime},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {V}anuatu subduction zone ({VSZ}) is known to be seismically very active, due to the high convergence rate between the {A}ustralian and {P}acific tectonic plates for the majority of the margin. {H}owever, this is not the case on its southernmost part south of latitude 22.5 degrees {S} and east of longitude 170 degrees {E}, which is neither highly tectonically active nor has it produced large tsunamis over the past 150 years. {I}t has also not been widely studied. {O}n the 11 {F}ebruary 2021 (10 {F}ebruary {UTC}), a magnitude {M}-w 7.7 earthquake triggered a tsunami warning in {N}ew {C}aledonia and {V}anuatu 20 min after midnight (local time). {W}ith an epicentre located close to the volcanic islands of {M}atthew and {H}unter, this shallow reverse-faulting rupture (< 30 km depth) was able to deform the seabed and produce a tsunami. {T}his was confirmed 45 min later by the coastal gauges of the {L}oyalty and the south {V}anuatu islands, which recorded the first tsunami waves. {S}howing a typical recorded amplitude of less than 1 m, with a maximum of similar to 1.5 m in {L}enakel ({T}anna, {V}anuatu), it was observed on most coastal gauges and {DART} stations in the south-west {P}acific region as far as {T}asmania to the south and {T}uvalu to the north at distances of similar to 3000 and similar to 1800 km from the epicentre. {I}n this study, the tsunamigenic potential of the southernmost part of the {VSZ} and the implications in terms of regional hazard assessment are discussed through (1) the presentation of the complex tectonic settings of this "transition zone" between the {S}olomon-{V}anuatu and the {T}onga-{K}ermadec trenches, (2) the case study of the 10 {F}ebruary 2021 tsunami at a south-west {P}acific regional scale using three different tsunami generation scenarios computed with the {COMCOT} modelling code on a set of 48 nested bathymetric grids, and (3) the simulation of a plausible {M}-w 8.2 scenario encompassing the active part of this "transition zone". {T}he validation of the {M}-w 7.7 parameters for tsunami modelling provides the means to further assess the hazard from potential tsunamis triggered by higher magnitude earthquakes in this region. {T}sunami records highlight that > 28 cm wave amplitudes were recorded at eight different coastal gauges, including one with an amplitude of more than 1 m ({L}enakel, {T}anna, {V}anuatu). {T}he tsunami threat at that location would be large enough to warrant an onshore evacuation. {F}inally, it helps to highlight the significant role played by the numerous submarine features in the region, the {N}orfolk {R}idge being the most important, which acts like a waveguide from the north to the south.},
  keywords = {{PACIFIQUE} {ILES} ; {VANUATU} ; {PACIFIQUE} {SUD} ; {MATTHEW} {ILE}},
  booktitle = {},
  journal = {{N}atural {H}azards and {E}arth {S}ystem {S}ciences},
  volume = {23},
  numero = {2},
  pages = {393--414},
  ISSN = {1561-8633},
  year = {2023},
  DOI = {10.5194/nhess-23-393-2023},
  URL = {https://www.documentation.ird.fr/hor/fdi:010086960},
}