SEDIMENTATION AND EROSION AT THE WEICHSELIAN ICE-MARGINAL ZONE NEAR GOLCZEWO, NORTHWESTERN POLAND

The Golczewo end moraine was formed during the general ice-sheet reces sion after the Pomerania Phase of the Late Weichselian glaciation and represents a short period of steady state conditions at the ice-sheet margin. The end moraine is a SW-NE oriented zone formed of several, is olated, 10-15 m high ramparts, separated by low areas ('gates'). The e nd moraine zone is located along the axis of the elevated Jurassic bed rock that much influenced the subglacial hydrology. The Golczewo end m oraine is formed of two types of subaerial fan. Its major, and morphol ogically exposed part (hills), is represented by short, glacial-termin al fans. These fans have been partly eroded, especially at tunnel vall ey mouths. The eroded zones ('gates') have been filled with fluvial de posits forming flat sandur fans that extend across the end moraine for eland (plain). These morphological units (ramparts, 'gates' and sandur fans) which together form the end moraine zone, were formed synchrono usly. The ramparts are distinctly elongate hills, commonly asymmetrica l, with steep proximal slopes. They comprise a complex sedimentary seq uence that suggest alternating phases of sediment gravity flows and fl uvial sheet floods. Flow tills indicate the ice-contact conditions. Th e 'gates' between hills and sandur fans are flat to gently inclined. T hey were formed by braided rivers, with sheet floods dominating at the fan apexes at the 'gates' and channelised braided rivers in more dist al parts. (C) 1997 Elsevier Science Ltd.