Permian-Triassic high thermal regime in the Alps: Result of late Variscan collapse or continental rifting? Validation by numerical modeling

摘要: [1] The Permian-Triassic igneous activity, associated with regional scale deformation developed under high-temperature/low-pressure (HT-LP) metamorphic conditions and widely recorded in the pre-Alpine crust of European Alps, can result from late orogenic collapse a collisional belt or lithospheric thinning leading to continental rifting process. In order reduce this ambiguity, we use two-dimensional finite element model give new insights on sequence mechanisms operating during active ocean-continent convergence, followed by collision pure gravitational evolution geodynamic interpretation Paleozoic-Mesozoic Alpine area. The modeling predictions are compared PT climax Variscan metamorphism affecting Helvetic Southalpine domains. good agreement between natural data realized for early Neovariscan indicates that Paleozoic, Alps was part an convergence margin intracontinental suture zone. Furthermore, results support envisaging extension as responsible HT related intense activity. This precursor Mesozoic oceanization, which tectonic units, coupled accreted subduction collision, were separated form two passive Adriatic margins.