Composite memory variables for viscoelastic synthetic seismograms

Abstract

By rearranging terms in the viscoelastic wave equations for the standard linear solid, new composite memory variables are defined. Instead of having one memory variable for compressional relaxation and one for each of the six independent components of quasi‐shear stress relaxation, as in the standard relaxation mechanism formulation, the new grouping contains only one for each displacement response component. Thus, only two (rather than three) memory variables are required for 2‐D computations, and only three (rather than seven) are required for 3‐D computations. The amount of computation is not changed as the new formulation is equivalent to the standard one, but there is a significant saving in computer memory. Copyright © 1995, Wiley Blackwell. All rights reserved