Changing patterns of shortening and lateral extension, Exhumation of the Eastern Alpine orogenic core, Strain partitioning during orogenic indentation

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We seek to understand how folding and extensional faulting accommodated lateral motion of orogenic crust at the eastern end of the Tauern Window in the Eastern Alps. This is key to determining how Alpine-type mountain belts grow, both vertically and laterally, during plate indentation. We will test the idea that eastward lateral motion of this part of the Alps in response to Miocene-to-present indentation of the Adriatic microplate involved increasing amounts of extensional exhumation from N to S (towards the Adriatic indenter) and that this extensional exhumation was diachronous: Initial activity of the Katschberg mylonite belt during or possibly even before km-scale folding (Hochalm dome) yielded to brittle, high-angle normal faulting (possibly still active?) as folding migrated northwards to the sinistral transpressive SEMP fault that bounds the northeastern part of the Tauern Window. To determine the age, rates and amounts of extensional exhumation, we will lay a series of structural-geochronological transects across and along the Austroalpine-Penninic contact. This will involve Rb/Sr microsampling, Ar/Ar in-situ laser dating and zircon and apatite fission-track campaigns to constrain the entire thermal and kinematic history of doming and orogen-parallel extension. The project requires one research assistant (BATIIa/2) to be employed by the DFG, and funds to support the activites of a second research assistant (Dipl.-Min. Andreas Scharf) already employed by the FU Berlin .