The sediment budget of circum-Alpine basins has been quantified in order to compare sediment masses derived from the northern (western) versus the southern (eastern) flank of the Alps. The evolution of the major catchment areas since Oligocene times is shown in a series of sketch maps. A fast shift of the drainage divide towards the N at ∼ 17 Ma and back to the S at ∼ 11 Ma is deduced in the Swiss and Western Alps. The shifts affected a catchment area of -6,000 and ∼ 13,000 km2 in size, respectively. Since no indications of a relevant asymmetry in climate, especially contrasting precipitation, exist in Miocene times for the two opposite flanks of the orogen, a tectonic explanation for the shifts of the drainage divide is favoured. Important catchment reorganizations in the Alpine foreland, occurring also at 17 Ma and 11 Ma, were forced by Alpine collision and uplift in Lower Austria (Amstetten swell, as part of the Bohemian massif), and thrusting and uplift of the Swiss Jura, respectively.
|Number of pages||27|
|Journal||Zeitschrift fur Geomorphologie|
|Publication status||Published - Jan 1 2001|
ASJC Scopus subject areas
- Geography, Planning and Development
- Earth and Planetary Sciences (miscellaneous)