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of the younger Saalian ice margin stagnation in eastern Poland: development of a regular pattern of glaciolacustrine kames. Geografiska Annaler: Series A, Physical Geography, ABSTRACT. Glaciolacustrine kames in the Bielsk Podlaski area (eastern Poland) exhibit a unique regular pattern. Three representative morphological kame types were chosen for detailed sedimentological analyses, specifically: isolated, isometric mounds; isolated, elongated hills; and branching ridges. All types comprised fine-grained sandy and sandy/ silty deposits. Lithofacies analysis resulted in the distinction of several lithofacies associations. Associations dominated by medium-or large-scale, massive or horizontally laminated sands are interpreted as proximal subaqueous fans; associations dominated by medium-or small-scale lithofacies of ripple-drift cross-laminated sand are interpreted as distal subaqueous fans; and those dominated by sandy/silty, silty or silty/clayey lithofacies with horizontal lamination are interpreted as lake bottomsets. Rates of sediment accumulation appear to have been fast, resulting in syndepositional and metadepositional deformation structures of two types: water-escape structures, and slumps on subaqueous slopes. After the ice-walled lake basins filled with sediment, glaciofluvial erosion and deposition alternated, resulting in erosional channels of up to 1 m deep, later filled with gravel or gravely sand. The results indicate that kames developed in a supraglacial environment within a topography of ice-cored moraines containing ice-walled lakes that persisted due to the presence of permafrost. Pauses during retreat of the ice walls resulted in ice-contact deformations at the edges of the kames. Kame formation is therefore consistent with a continental climate and this may explain the increased abundance of this type of kame system in Eastern Europe.

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