Discrete visco‐elastic lattice methods for seismic wave propagation

Abstract

2D and 3D discrete particle or lattice methods for the simulation of seismic waves are presented for different visco‐elastic media. It is demonstrated that a numerical implementation of the method is capable of modelling visco‐elastic seismic wave propagation. Lattice methods represent the medium under investigation as particles or nodes interacting through local force rules. Three schemes are developed, a Maxwell body, a Kelvin‐Voigt body and a Zener Body (or standard linear solid). The force acting between particles is chosen to represent each of these different rheologies. Each of these schemes was tested against analytical solutions for wave propagation in 2D and 3D unbounded visco‐elastic media. The seismograms generated for each different rheology fit well with the expected theoretical seismograms with the maximum misfit error energy being less than 3% for each different rheology. As such, lattice methods offer an alternative approach to seismic wave modelling in elastic and visco‐elastic media.