Theoretical deformations of the Earth's crust induced by the polar motion - A case study of New Zealand

We investigate the long-term Earth's crustal deformations in New Zealand induced by the polar motion over the period from 1962 to 2009 using a tidal theory of an elastic and oceanless Earth. The theoretical values of crustal deformations are compared for the Gutenberg-Bullen, Ocean-Mantle, Shield-Mantle, 1066A, and PREM models of the Earth. The horizontal and vertical deformations computed using these models differ less than 0.1 mm and 0.15 mm, respectively. The maximum horizontal motion in New Zealand is less than 4 mm over the period from 1962 to 2009. The maximum vertical motion is larger by a factor of about 3 (up to 12.2 mm). The variations in horizontal and vertical motions at different locations within New Zealand are bellow 1 and 3 mm, respectively.