Thermochronology meets cosmogenic nuclides - comparing Pleistocene landscape denudation and catchement erosion rates

Publication Type  Miscellaneous
Year of Publication  2008
Authors  Schaefer, J. M.; Thomson, S.; Reitz, M.; Finkel, R. C.; Seeber, L.
Prepared for  American Geophysical Union, Abstract
Key Words  Cosmogenic Radionuclides, Thermochronology
Abstract  

The rapid Pleistocene uplift of Calabria is a key parameter for better understanding the complex tectonics of the Calabrian Arc, but quantitative constraints are sparse. The Calabrian Arc is the last segment of a formerly larger subduction zone that is still consuming oceanic crust. The Apennines and Sicilian mountain chains on either side are now in collision, but Calabria is the region experiencing rapid uplift. The uplift of Calabria is directly linked to landscape denudation rates. Here we present a combination of long-term denudation rates derived by (U+Th)/He thermochronology and late
Pleistocene basin-wide erosion rates derived from cosmogenic ¹⁰Be and ²⁶Al inventories of river sediments. We focus on two main drainage systems in Calabria, Mucone and Mesima Rivers. The Mucone River drains the uplifted Sila Plateau in northern Calabria and traverses longitudinally the extensional Crati Valley. The Mesima River starts in the Serre range of central Calabria and drains the Mesima basin, another extensional graben aligned with the Crati Valley. Both these rivers display profiles characteristic of young plateaus: A gently dipping upper reach, a steep middle reach, and a shallowly dipping lower reach. We expect the data to clarify whether there was a significant late Pleistocene increase in uplift rates, improved resolution on the timing, and whether this acceleration of uplift occurred throughout Calabria. We will
discuss the impact of our results for models of the tectonic evolution of the Calabrian Arc.