New constraints on the exhumation history of the western Tauern Window (European Alps) from thermochronology, thermokinematic modeling, and topographic analysis

Abstract The Brenner normal fault bounds the Tauern Window to west and accommodated a significant portion of orogen-parallel extension in Eastern Alps. Here, we use zircon (U–Th)/He, apatite fission track, (U–Th)/He dating, thermokinematic modeling, topographic analysis constrain exhumation history western footwall fault. ZHe ages from an E–W profile (parallel slip direction fault) decrease westwards ~ 11 8 Ma suggest fault-slip rate 3.9 ± 0.9 km/Myr, whereas AFT AHe show no spatial trends. elevation indicate apparent rates 1.1 0.7 1.0 1.3 respectively, are again spatially invariant. Most thermochronological well predicted by model with that slips at 4.2 km/Myr between 19 9 produces 35 10 km extension. modeling reveals invariant caused heat advection due faulting posttectonic thermal relaxation. enigmatic increase K–Ar phengite biotite towards is conduction hot cooler hanging wall. Topographic profiles across N–S valley 1000 300 m erosion after ceased, which agrees results our model. Valley incision explains why located on shoulder not bottom. We conclude ability models quantify transfer rock crucial for interpreting cooling extensional systems.