| Abstrakt: |
The Calabrian block, along with Alboran, Kabylies, and Peloritani form isolated and enigmatic igneous/metamorphic terranes (AlKaPeCa) stacked over the Meso‐Cenozoic sedimentary successions of the Apennines and Maghrebides. They are commonly interpreted as fragments of the Hercynian chain rifted apart from Europe during Jurassic Alpine Tethys spreading, drifted southward during Neogene roll‐back of (Neo) Tethyan slab fragments for hundreds of kilometers on top of nappe piles. We report on the paleomagnetism of upper Triassic‐lower Miocene sedimentary rocks from the Longobucco succession that is transgressive over the crystalline Sila Massif (NE Calabria). Well‐defined magnetization directions carried by hematite were isolated in 10 sites (122 samples) in Jurassic rocks. Nine Toarcian and one Tithonian Ammonitico Rosso sites yielded a dual polarity "A" magnetization component whit a direction over 40° from the geocentric axial dipole (GAD) field direction, that supports a positive fold test. Five sites yielded a "B" normal polarity component NE (<40°) of the GAD direction characterized by a negative fold test. We interpret the B component as a Miocene magnetic overprint later clockwise rotated by ∼20° during the well‐known Pleistocene (1–2 Ma) rotation of Calabria. When corrected for such rotation, the A component defines a ∼160° counterclockwise (CCW) rotation of the Calabrian block with respect to Europe. Of these, ∼90° likely occurred along with Corsica‐Sardinia block during its Eocene‐Miocene rotation from the Provençal margin. Thus, the Calabrian block underwent an additional Cretaceous‐Eocene 70° CCW rotation that we relate to Early‐mid Cretaceous >500 km left‐lateral transcurrent motion between Africa and Europe. Key Points: First pre‐Miocene paleomagnetic data from the AlKaPeCa terranes. Sites in Jurassic rocks reveal a 160° counterclockwise rotation of CalabriaAbout 90° occurred with Corsica‐Sardinia in the Eocene‐Miocene. Additional 70° Calabria rotation took place in the Cretaceous‐EoceneEarly Cretaceous left‐lateral shear at Africa‐Europe margin induced Calabria rotation [ABSTRACT FROM AUTHOR] |
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