𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Crustal uplift in the Alps: why the drainage pattern matters

✍ Scribed by Fritz Schlunegger; Matthias Hinderer


Book ID
104463332
Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
505 KB
Volume
13
Category
Article
ISSN
0954-4879

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✦ Synopsis


The Alpine drainage system comprises two large orogen‐parallel drainage basins in the core of the Alps (the Rhone and Rhine valleys), and smaller orogen‐normal orientated systems. Discharge of the large rivers is ≈5–10 higher than that of the small ones. In addition, the courses of the Rhone and Rhine Rivers are trapped by faults and thrusts that display lower erosional resistance than the neighbouring lithologies. Enhanced discharge of these rivers and the low erosional resistance of their bedrocks potentially enhances surface erosion. Indeed, present‐day and glacial sediment yields are ≈1.6–1.7 times higher in these valleys than in the orogen‐normal systems. Interestingly, rates of crustal uplift are also enhanced in the Rhine and Rhone valleys, where current rates of ≈1.4–1.6 mm yr^−1^ are measured. The spatial coincidence between the location of enhanced erosion and maximum crustal uplift rates are interpreted to reflect a positive feedback between surface erosion and tectonic forcing.