Landscape development of Amrum´s west coast (Southern North Sea): GPR and sedimentology

The aim of the study is to reconstruct the landscape development on the seaward side of the North-Frisian Island of Amrum. An integrated approach using GPR and sedimentological analyses of shallow sediment cores drilled at selected sites along the radar profiles has been applied. Based on these data a sedimentary model was generated that describes the landscape development on the seaward side of the island during the Holocene. The main focus lies on the reconstruction of the sedimentary environment as well as of the coastline of the island´s west coast before the barrier sandbar of the so-called Kniepsand was connected to the island. Furthermore the process of barrier sandbar attachment to the Pleistocene island core was summarized. The study figured out that the conditions for sedimentation had been quite different in previous times. Before the sandbar was connected to the island, tidal flat deposits had been accumulated in a low energy environment. Tidal flat deposits show a general coarsening upward trend and turn into overlying coarser grained beach deposits. Old cliffs formed through several storm surges are also preserved in GPR data and may redraw old sea level positions.