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post-orogenic extension. Our new kinematic results in combination with previous works in the Cyclades area reveal a regional scale change in tectonic transport direction from (W)NW-(E)SE at Late Cretaceous-middle Eocene to (E) NE-(W)SW at late Eocene-Oligocene times. The observed change in transport direction may be governed by the relative motion of Africa with respect to Europe during Alpine orogeny.

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Current tectonic models interpret the Hellenides as a unidirectional, SW‐vergent orogenic belt. New (micro‐)structural and amphibole chemistry analyses show, instead, that the exhumation of the Pelion Blueschist Nappe (PBN) of the Internal Hellenides was achieved by retroward (ENE)‐directed ductile extrusion, which opposes the principal (proward) orogenic vergence. Retroward extrusion occurred between two sub‐parallel, major ductile shear zones (Basal thrust and Upper detachment) with opposite shear senses, which operated simultaneously under blueschist‐ to greenschist‐facies conditions during the late Eocene–Oligocene. Because the PBN is tectonically sandwiched between Pelagonian basement rocks, we suggest that the PBN protolith was accumulated during the Late Cretaceous in an incipient backarc basin developed above the NE‐dipping subduction of the Pindos Ocean beneath the Pelagonian microcontinent. Subsequent Apulian–Pelagonian collision triggered basin inversion and the proward‐dipping intracontinental subduction that caused the early/middle Eocene blueschist‐facies metamorphism followed by the retroward extrusion of the PBN.

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