Lattice Boltzmann approach for hydro-acoustic waves generated by tsunamigenic sea bottom displacement

Abstract

Tsunami waves are generated by sea bottom failures, landslides and faults. The concurrent generation of hydro-acoustic waves (HAW), which travel much faster than the tsunami, has received much attention, motivated by their possible exploitation as precursors of tsunamis. This feature makes the detection of HAW particularly well-suited for building an early-warning system. Accuracy and efficiency of the modeling approaches for HAW thus play a pivotal role in the design of such systems. Here, we present a Lattice Boltzmann Method (LBM) for the generation and propagation of HAW resulting from tsunamigenic ground motions and verify it against commonly employed modeling solutions. LBM is well known for providing fast and accurate solutions to both hydrodynamics and acoustics problems, thus it naturally becomes a candidate as a comprehensive computational tool for modeling generation and propagation of HAW

Acoustic–gravity waves from multi-fault rupture

“…On the other hand, water compressibility and sea-bottom elasticity affect the phase speed of surface gravity waves and should be considered when accurate transoceanic tsunami modelling is sought Abdolali, Kadri & Kirby 2019). The peak frequency shift and attenuation of acoustic-gravity waves takes place due to interaction with a visco-elastic sedimentary layer at the sea bottom (Abdolali, Kirby & Bellotti 2015b;Prestininzi et al 2016).…”

“…The peak frequency shift and attenuation of acoustic–gravity waves takes place due to interaction with a visco-elastic sedimentary layer at the sea bottom (Abdolali, Kirby & Bellotti 2015 b ; Prestininzi et al. 2016).…”