Elbe Line Project This project aims at investigating by teleseismic receiver functions and seismological tomography, the crust and upper mantle along a north-south oriented profile about 350 km long from around the town of Ringkøbing in western Jutland to south of Hamburg in northwestern Germany. A number of tectonic processes have affected the crust and uppermost mantle beneath southern Scandinavia and northern Germany: Precambrian crustal accretion in southern Baltica, Caledonian collision between Baltica and Avalonia along the Tornquist Suture Zone, followed by Variscan collision and formation of the North German and the Norwegian-Danish basins, and more recent magmatic activity to the south. This study is particularly focused on the closure of the Tornquist Sea and the Caledonian collision between Baltica and Avalonia. The project is a cooperation between the University of Aarhus and the GFZ Potsdam.