We apply (U-Th-Sm)/He dating and fission-track thermochronometry of
apatites to the Adamello Complex located in the Southern European Alps.
Our goal is to constrain exhumation rates since the Miocene. in
particular, to determine whether the increase in sedimentation
documented in the foreland basins since 5 Ma is recorded in cooling
rates of the Southern Alps. Thermochronometry provides a cooling rate
for rocks, which can be converted to an exhumation rate through thermal
modeling, thereby quantifying the amount of rock exhumed at different
time scales. Apatite fission-track and (U-Th-Sm)/He analyses all record
Miocene ages. We find no evidence for an increase in exhumation rate
during the Plio-Pleistocene. The results of our exhumation rate
estimates and tectono-geomorphic modeling suggest that unroofing during
thrust propagation of the Southern Alps in the Late Miocene drove most
of the exhumation, while changes in relief, mainly associated with
Plio-Pleistocene climate change, likely did not affect the Adamello
Complex. The findings from this study combined with other studies
highlight that there appears to be a gradient across the Alps, with more
intensive Plio-Pleistocene erosion in the Western and Central Alps
compared to the Eastern and Southern Alps. (C) 2012 Elsevier B.V. All
rights reserved.