CitcomSVE 3.0: A Three-dimensional Finite Element Software Package for Modeling Load-induced Deformation for an Earth with Viscoelastic and Compressible Mantle

Abstract. Earth and other terrestrial and icy planetary bodies deform visco-elastically under various forces. Numerical modeling plays a critical role in understanding the nature of various dynamic deformation processes. This article introduces a newly developed, open-source package, CitcomSVE-3.0, which efficiently solves the visco-elastic deformation of planetary bodies. Based on its predecessor, CitcomSVE-2.1, CitcomSVE-3.0 is updated to account for elastic compressibility and depth-dependent density, which are particularly important in modeling horizontal displacement for visco-elastic deformation. We benchmark CitcomSVE-3.0 against a semi-analytical code for two types of surface loading problems: 1) single harmonic loads on the surface and 2) the glacial isostatic adjustment (GIA) problem with a realistic ice sheet loading history (ICE-6G_D), in which an updated version of sea level equations is incorporated. The benchmark results presented here demonstrate the accuracy and efficiency of this package. CitcomSVE shows a second-order accuracy in terms of spatial resolution. For a typical GIA modeling with 122-ky glaciation-deglaciation history, surface horizontal resolution of ~50 km, and time increment of 125 yr, it takes ~ 3 hours on 384 CPU cores to complete with less than 5 % errors in displacement rates.