The effect of water depth on ice‐proximal glaciolacustrine sedimentation: Salpausselkä I, southern Finland

The morphology and sedimentology of the Salpausselkä I moraine in southern Finland were examined in detail, together with the distribution of associated eskers and the glacial geology of the surrounding area. Marked contrasts in the form and stratigraphy of the moraine suggest that there were differences in the style and pattern of sedimentation along the ice/lake interface. These variations were influenced by the lake water depth and the nature of the subglacial drainage system. Large individual deltas which built up to water level were the product of conduit focused sedimentation. Lower, narrower coalescing fans of finer material were formed at the ice grounding line by sediment fed from a distributed drainage system. Subglacial conduit systems were found to be unstable where marginal water depths were greatest, favouring the development of a distributed drainage system.