Publication Date:
2002
abstract:
We present data related to the water divide of the Apennines,
and its relation to the highest mountains. Frequently, the highest
mountains do not coincide with the divide, but they are rather located
toward the foreland to the 'east'. This is interpreted as induced
by the faster 'eastward' propagating tectonic wave generated by the
retreat of the Apennines subduction zone during Pliocene and
Quaternary times (10-30 mm/a) with respect to average denudation
rates (<1 mm/a). The vertical and horizontal offset of the highest
mountains with respect to the divide indicate tectonics are generally
faster than denudation rate when subduction rolls back in a
steady state, and lithologies of the outcropping belt are fairly
homogeneous. The slowing of the subduction, shaly lithologies in
the 'eastern' foreland slope, and transfer zones may instead determine
an offset of the highest mountains with respect to the divide
toward the hinterland to the 'west'.
The morphology of the Apennines is determined by undulations
of at least three different wavelengths: 1) at the belt scale
(about 150 km) controlled by subduction scale processes; 2) at the
grabens and horsts scale (about 5-15 km); 3) at the local scale (0.5-
3 km) as determined by the peculiar denudation rates. Along strike,
the divide shows a wavelength of 200-300 km, with vertical undulations
of 1000-1500 m, possibly due to structural transfer zones.
Iris type:
01.01 Articolo in rivista
Keywords:
Water divide; highest elevation; subduction
List of contributors: