A model of glacial tectonics, applied to the ice-pushed ridges in the central Netherlands.

Abstract

The Gelderse Vallei is a Saalian glacial basin filled with younger sediments, 40 km long and up to 20 km wide, running NNW- SSE. Thrust sheets which build up the ice-pushed ridges on either side of the valley were transported away from the centre of the basin. They are up to 25 m thick and are pushed to a level about 100 m above the decollement. Pore water pressure plays an important role by greatly reducing the sliding friction in the decollement layer. In the model proposed in the article, the energy to move and imbricate glacial thrust sheets around the margins of an ice lobe is supplied by the continuous flow of ice into the ice lobe. -from Author