# The relaxation of spherical and flat Maxwell Earth models and effects due to the presence of the lithosphere

## Main Article Content

## Abstract

The radial surface deflection of a spherical Earth model appropriate to time scales characteristic of glacial loading is compared with the associated half-space response. For that purpose the analytical solution for a Maxwell sphere surrounded by a thick elastic shell is derived under the assumption of incompressibility. The half-space approximation is deduced as a special case directly from the spherical solution. Comparison of the response spectra, for different thicknesses of the elastic shell, reveals only minor differences. In the spatial domain, the half-space approximation may, nevertheless, diverge significantly from the spherical solution. For a disk load radius *R* = 800 km (Fennoscandia), the half-space approximation is adequate, whereas it is usually inappropriate if *R* = 1600 km (Laurentia). The sensitivity of the response to the thickness of the elastic shell is also investigated. For *R* = 800 km, the surface deflection in the central region below the load is fairly diagnostic of the shell thickness. If *R* = 1600 km, the peripheral region is more sensitive to this parameter.

**ARK**: https://n2t.net/ark:/88439/y005336

Permalink: https://geophysicsjournal.com/article/210

## Article Details

*Journal of Geophysics*,

*56*(1), 24-33. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/210

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