Glacial deposits and ice‐sheet dynamics in the north‐central Baltic Sea during the last deglaciation

Nine seismic stratigraphic units were distinguished, and their distribution mapped, in an 80 × 130 km submeridionally oriented area in the north‐central Baltic Sea, east of Gotska Sandön and Farö. Analysis of these units revealed a great influence of the bedrock topography on the structure and distribution of the glacial deposits. Major glacially eroded valleys in the Baltic Clint, connecting the Faro Deep and the North Central Baltic Basin (Harff & Winterhalter 1996) across a narrow sill, form an extensive submeridional bedrock depression. The concentration of ice flow into this depression is reflected in the drumlinized surface of the till near the Baltic Clint. Large eskers in the elongated bedrock depressions and on the Ordovician Plateau mark the locations of former subglacial meltwater conduits. Termination of the eskers with extensive glacio fluvial outwash fans at the northern limit of the Farö Deep, the presence of subaquatic melt‐out till in the bottom of it, and wedge‐shaped ice‐marginal grounding‐line deposit on the Silurian Plateau suggest floating ice margin conditions in the low‐lying areas and a local ice shelf confined to the Frö Deep during the deglaciation.

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