Some properties of Norwegian tills

Grain size distribution data for a large number of basal tills from different areas are presented. The Norwegian tills can be divided in two major groups: Tills derived from Precambrian bedrock and tills derived from Cambro-Silurian sedimentary rocks. Both types are significantly different from Danish tills where unconsolidated sediments are incorporatcd. Chemical and mineralogical composition of the 125–250 μm fraction of tills derived from Precambrian rocks and tills derived from phyllites are presented. These data are used to determine transport distances for the till material.
Due to a marked relief and short distances from the ice-divides to the coast, the tills found in the Norwegian mountains have generally had a short transport and are, unless large amounts of unconsolidated sediments are incorporated, strongly influenced by the underlying bedrock.