32. Klagenfurt Basin: A Large Basin in the Alps

The Klagenfurt basin is the second-largest basin of the Alps and hosts the socioeconomically most important subregion of Austria’s federal state Carinthia. This chapter focusses on the basin’s extraordinary variety of landforms and their evolution. The basin itself is a flexural basin that developed by a downwarping of the crust under the load of the northward moving Karawanken Mountains. During the LGM, almost the entire basin was covered by an ice sheet, which was important for the development of the basin’s landscape, characterized by many lakes such as Lake Wörthersee. The last glaciation also explains why rivers such as the Gurk do not follow a N–S course—as would be expected because of the flexure—but rather show a peculiar river network. Two exemplary subregions of the basin that are of special morphological interest are portrayed. The Sattnitz plateau consists of Neogene conglomerates, which are interpreted as sediments from the Karawanken Mountains. However, the areas of erosion and sedimentation are separated from each other by the current valley of the Drau River. This section of the Drau Valley is therefore younger than other sections and only has developed during the Pleistocene. Finally, the Krappfeld, a northern subbasin of the Klagenfurt basin, is discussed with special attention to its glaciofluvial sediment filling and its position to the neighbouring glaciation systems during the Pleistocene.