HR: 08:45h
AN: OS21E-04    [Abstracts]
TI: Dynamical Simulation of Subaerial and Submarine Landslides Detaching From the Volcanic Island of Stromboli, Italy: a Sensitivity Analysis
AU: Zaniboni, F
EM: Filippo@ibogfs.df.unibo.it
AF: Dipartimento di Fisica, Settore di Geofisica, University of Bologna, Viale Carlo Berti Pichat, 8, Bologna, 40127 Italy
AU: * Tinti, S
EM: steve@ibogfs.df.unibo.it
AF: Dipartimento di Fisica, Settore di Geofisica, University of Bologna, Viale Carlo Berti Pichat, 8, Bologna, 40127 Italy
AB: Stromboli is an active volcano that is found in the southern Tyrrhenian sea, Italy, and is known to be unstable. In addition to large lateral collapses in the order of 1 cubic kilometre that were ascertained to occur several times in the last 13000 years, the volcanic cone is affected by mass failures involving volumes of millions of cubic metres, that may generate tsunamis. These slides are usually concomitant with the paroxysmal eruptions of the volcano that repeated on average every 15-20 years in the last century. The last documented case is the double tsunami that took place on December 30, 2002, and was induced by two main episodes of failure, occurring only 7 minutes apart in the north-west flank of Stromboli, known as "Sciara del Fuoco" (SdF). The tsunamis were very damaging and hit the northern coast of Stromboli with wave heights larger than 10 meters in several places. In this work we perform numerical simulations of slides that are supposed to detach from the subaerial and submarine portion of the SdF. The simulations are carried out by applying an enhanced Lagrangian model that was originally implemented by Tinti et al. (1997). It is a centre-of-mass model, and consists in dividing the mass in a chain of blocks (1D) or in a matrix of blocks (2D) that are allowed to deform: the motion of each centre of mass is computed, depending on the geometrical characteristics of the sliding body and on the environmental conditions (basal friction, drag and shear resistance exerted by the water, etc.). The sensitivity analysis we have performed enables us to determine the influence of the initial volume, geometry, position, density, etc. of the body on the dynamical evolution of the sliding (trajectory, velocity, etc.) and on the final run-out distances, and to make some inferences on the main characteristics of the generated tsunami.
DE: 4564 Tsunamis and storm surges
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting