Striae and fabric analyses in a moraine exposure in Västerbotten, N. Sweden

Abstract

Field and laboratory investigations were made of till deposits in the county of Västerbotten, northern Sweden, with, regard to their stratigraphy, morphology, relations to ice movements, texture and structure, lithology, morphometry and fabrics of pebbles and cobbles. At one locality striae and two till sheets were especially investigated. In the lower sandy till the pebbles and cobbles have a long-axis orientation roughly parallel with the direction of the final, probably topographically deflected, ice movement from the NE. In the upper coarser till the long axes of the pebbles and cobbles are also parallel with this movement, with a slight “up-glacier” dip. The till sheets contain lenses, thin layers and contortions of gravel, sand and silt. It is stressed that records of the granulometry, morphometry and lithology of the particles included in the fabric analyses are necessary to obtain adequate information about the depositional environment.