Constraining the process of intracontinental subduction in the Austroalpine Nappes: Implications from petrology and Lu?Hf geochronology of eclogites

High- and ultrahigh-pressure rocks occur in the Austroalpine Nappes a ~400 km long belt from Texel Complex west to Sieggraben Unit east. Garnet growth during pressure increase was dated using Lu-Hf chronometry. The results range between c. 100 90 Ma, indicating short-lived period of subduction. Combined with already published data, our estimates metamorphic conditions indicate field gradient increasing temperature northwest southeast, where experienced metamorphism. P-T eclogites generally lie on ‘warm’ side global subduction-zone conditions. oldest Cretaceous (c. Ma) are found Saualpe-Koralpe area derived widespread gabbros formed Permian Triassic rifting. In garnets showing two phases yielded Variscan-Eoalpine mixed age re-subduction Variscan eclogite-bearing continental crust Eoalpine orogeny. Jurassic blueschist-facies metamorphism at Meliata Western Carpathians eclogite-facies separated by time gap 50 Ma therefore do not represent transition oceanic subduction but rather separate events. Thus, we propose that initiation intracontinental site rift.