Journal
LITHOSPHERE
Volume 5, Issue 2, Pages 211-225Publisher
GEOSCIENCEWORLD
DOI: 10.1130/L243.1
Keywords
-
Categories
Funding
- Agence National de la Recherche-Erosion
- Relief Development in the Western Alps grant
Ask authors/readers for more resources
Apatite and zircon fission-track analysis and single zircon fission-track-U/Pb double dating of Oligocene to Miocene pro- and retro-side foreland basin sedimentary rocks provide evidence for short-lived but fast erosional exhumation of at least 1.5-2 km/m.y. in the internal western Alps between ca. 30 and 28 Ma. This period of fast erosion is seen as a result of rapid surface uplift coupled with increasing orographic precipitation during this phase of orogenesis. Surface uplift may have been caused and sustained by different plate-tectonic processes such as a change in convergence direction, intermediate-depth slab breakoff, and emplacement of the Ivrea body during continental collision. The occurrence of contemporaneous volcanic activity on the pro-side of the western Alps on the subducting European plate between ca. 36 Ma and 30 Ma is seen in connection with slab rollback of the Apennine slab and upwelling of hot mantle material beneath the western Alps. Single zircon double dating shows that the exhumational signal in the detrital thermochronologic data is not compromised by volcanically derived zircons, as volcanic grains can be identified and removed from the zircon fission-track data set to obtain a pure exhumational signal. The signal of fast exhumation is observed in the zircon fission-track data of the pro-side foreland basin and in the apatite fission-track data and published 40Ar-39Ar data in the retro-side foreland basin. During late Oligocene times, erosion rates slowed down to rates similar to present-day erosion rates in the western Alps.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available