Coexisting geodynamic processes in the Sicily Channel

The northwestern side of the Sicily Channel in the central Mediterranean has been shaped by the occurrence of two independent tectonic processes that overlap each other, the Maghrebides-Apennines accretionary prism and the Sicily Channel rift. Since at least the Pliocene, these two processes have acted simultaneously, being respectively related to the Apennines subduction and to the African rift. Thrust sheets of the accretionary prism crosscut the almost orthogonal rift-related normal faults and vice versa. Analog modeling supports the kinematics inferred from regional structural data. Alkaline magmatism associated with the rift is more pronounced in the foreland of the prism, where the extension is more concentrated. This peculiar setting confirms how independently geodynamic processes can interact in the same area at the same time, suggesting that plate boundaries are passive features responding to far-field velocity fields of the lithosphere.