6-7 February 2014 – ASTARTE WP3 – Rome
POSSIBLE TSUNAMIS GENERATED BY THE ROCKALL
LANSLIDES OFF THE WEST COAST OF IRELAND
Frédéric DIAS
Dimitra SALMANIDOU
School of Mathematical Sciences
University College Dublin
6-7 February - ASTARTE – WP3
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SUBMARINE FAILURE MECHANISMS AND TSUNAMIS
•Landslide generated tsunamis can attain extreme
Lituya Bay, Alaska 1958.
heights:
•Key factors controlling initial tsunami characteristics:
Landslide water depth, Volume of the material, initial
acceleration, maximum velocity, initial position of the sliding
material, type of failure (Hunt et al.,2011).
•The hazard varies regarding the:
•Landslide scale
•Location
•Type of the event
•The process
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THE ROCKALL BANK SLIDE COMPLEX,
NE ATLANTIC OCEAN.
The Real Map of Ireland and study area, www.marine.ie.
6-7 February - ASTARTE – WP3
THE ROCKALL BANK SLIDE COMPLEX,
NE ATLANTIC OCEAN.
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Large Slide Complex, 430km west of Ireland.
Width-to-length aspect ratio: 120x150km.
Estimated volume of collapsed material: 265-765km^3.
Evidence for a multiphase slope collapse
(Georgiopoulou et al.,2013).
•
Three suggested episodes of instability since
16,000 BP:
1) South upper slope, 2) North upper slope, 3) Lower slope.
•
Repetitive sliding phenomena and large sediment volumes
raised concerns for the hazard risk in the area.
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THE ROCKALL BANK SLIDE COMPLEX,
NE ATLANTIC OCEAN.
Shaded relief map of the study area, Georgiopoulou et al., 2013.
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RESEARCH TOOLS
•The landslide model
•Rigid body of prescribed shape and physical
properties
•Numerical simulation of the landslide trajectory and
speed.
•1D and 2D bathymetry.
•The VOLNA code (Dutykh et al.,2011):
•Nonlinear Shallow Water Equation Solver
•Finite Volume Method
•Efficient simulation of the complete life cycle of
tsunamis (generation, propagation and inundation).
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ONGOING RESEARCH
•Coupling of the landslide model and the VOLNA
numerical code for tsunami waves.
•2D numerical simulation of the event based on:
•The bathymetry of the area represented with the use
of mathematical functions.
•Real bathymetry data deriving from the bathymetric
data sets for the world’s oceans (GEBCO).
• Computation of the tsunami magnitude and
expected run-up on the Irish shoreline.
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