Glacial geomorphology of the south Swedish uplands – focus on the spatial distribution of hummock tracts

Abstract

We present the first comprehensive glacial-landform map of the south Swedish uplands (SSU), deglaciated 15–13 ka ago, using one consistent method and dataset; a Light Detection and Ranging-derived digital elevation model. In particular, this map focuses on the spatial distribution of hummock tracts. The distribution of hummock tracts reinforces previous thinking of a broad lobate east–west zone of hummocks across the southern part of the SSU. But this map also reveals a pattern of hummock tracts confined in what we call hummock corridors that have a radial pattern sub-parallel to the overall ice-flow direction. Hummocks occur in a wide variety of morphologies, but we also show the distribution of two distinct forms: V-shaped hummocks and ‘ribbed moraine’. Cross-cutting relationships between hummocks and glacial lineations indicate a more complex chronology than previously suggested. In places, lineations are overlain by hummocks and in other places hummocks are overlain by lineations. Additionally, directional variation of glacial lineations together with a complex end-moraine pattern suggests a dynamic ice sheet with multiple small lobes. Finally, mapped end moraines help to better correlate the deglacial timescales of western and eastern Sweden.

Keywords

• Glacial geomorphology
• hummocks
• southern Sweden
• deglaciation
• paleo-glaciology