The backbone of Alpine-type orogens: assessing the role of rift inheritance

Abstract

Assessing the relative role of rift-inherited hyper-extension and subduction/collisional dynamics in establishing the lithostratigraphic associations and overall architecture of orogens has key implications for constraining convergent margin dynamics. Giorgio Vittorio Dal Piaz, with his seminal papers across the late '90's and early 2000's, first suggested that seemingly unrelated Jurassic ophiolites, Paleozoic continental basement and Triassic shelf sediment from the Zermatt-Saas Zone were already part of a Jurassic ocean-continent transition zone, prior to undergoing eclogite facies metamorphism during the Alpine orogeny. Subsequent studies, performed in other parts of the Western Alps and Alpine Corsica provided further evidence that a large part of the apparent complexity of the axial zone of Alpine-type orogens may be a result of rift inheritance.