New information on the geodynamic development and the provenance for Carboniferous to Permian successions exposed within the Carnic Alps is supplied by an integrated approach of microprobe analysis and ⁴⁰Ar/³⁹Ar dating of detrital white mica. ⁴⁰Ar/³⁹Ar analyses of detrital white mica concentrates (4–10 grains) from syn- and post-orogenic Mississippian to Late Permian successions display an apparently uniform population and time lag of the isotopic ages with respect to the stratigraphic age of their host rock: early Variscan ages (373–396 Ma) are reported within syn-orogenic Visean-Namurian turbiditic sandstones, Variscan ages (333–309 Ma) in post-orogenic Pennsylvanian and Permian terrestrial and shallow marine sandstones. Detrital white micas from Mississippian syn-orogenic sandstones indicate an intermediate time interval between the cooling of the source rock and deposition, typical for compressional accretionary wedge settings. Furthermore, these ages argue for a Middle Devonian tectonothermal event in the hinterland. Detrital white micas from Pennsylvanian sandstones indicate a very narrow time lag between post-Variscan cooling of the source region and the depositional age. This points to a rapid exhumation of rocks in the source region from mid-crustal levels prior to the deposition of these sediments.