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-The late Eocene -early Miocene Alpine-Carpathian fold-and-thrust belt (FTB) lies in the transition between the Eastern Alps and the Western Carpathians, SE of the Bohemian crystalline massif. Our study shows the involvement of crystalline basement from the former European Jurassic continental margin in two distinct events. A first extensional event coeval with Eggerian-Karpatian (c. 28-16 Ma) thin-skinned thrusting reactivated the rift basement fault array and resulted from the large degree of lower plate bending promoted by high lateral gradients of lithospheric strength and slab pull forces. Slab break-off during the final stages of collision around Karpatian times (c. 17-16 Ma) promoted large-wavelength uplift and an excessive topographic load. This load was reduced by broadening the orogenic wedge through the reactivation of the lower-plate deep detachment beneath and ahead of the thin-skinned thrust front (with the accompanying positive inversion of the basement fault array) and ultimately, by the collapse of the hinterland summits, enhanced by transtensional faulting. Although this work specifically deals with the involvement of the basement in the AlpineCarpathian Junction, the main conclusions are of general interest to the understanding of orogenic systems.

<p>Quaternary landscape evolution in the Vienna Basin and the adjacent area west of its subsiding area is controlled by sediment redeposition, aggradation and erosion of the Danube, local normal faulting, and overall regional uplift. Glacial - interglacial climate dynamics highly influence the hydrodynamics and amount of sediment transport. Over the last 9 years sediments exposed during construction and drilling as well as from surface outcrops were sampled for cosmogenic nuclide age determination and uplift/incision rate calculation.</p> <p>The Vienna Gate marks the transition of the Danube alluvial plain in the west (Tullnerfeld) into the extensional structure of the Vienna Basin. At this border, the Danube flows on top of an approximately 2 km wide segment of Penninic Flysch units before it enters the Vienna Basin to the east. Within the transtensional structure of the Vienna Basin, several fault blocks record local uplift and subsidence. Outside of the Vienna Basin, regional uplift is documented by fluvial terrace deposits at elevated positions located at different heights above the recent Danube riverbed.</p> <p>The current status and tectonic context of numerical ages ranging between 250 kyr and 3 Ma will be presented in detail at the conference. Few locations appear to be sedimentologically unsuitable for cosmogenic nuclide burial age dating, those scenarios will be explored and discussed.</p> <p> </p> <p>Funding: HJS 318325/2018; OMAA 90ou17; OMAA 98ou17; NKFIH FK124807</p>