Late Quaternary deformation on the island on Pantelleria: new constraints for the recent tectonic evolution of the Sicily Channel rift (southern Italy)

Structural observations carried out on the volcanic Island of Pantelleria show that the tectonic setting isdominated by NNE trending normal faults and by NW-striking right-lateral strike-slip faults with normalcomponent of motion controlled by a ≈N 100◦E oriented extension. This mode of deformation alsocontrols the development of the eruptive fissures, dykes and eruptive centres along NNE–SSWbelts thatmay thus represent the surface response to crustal cracking with associated magma intrusions. Magmaticintrusions are also responsible for the impressive vertical deformations that affect during the Late Quaternarythe south-eastern segment of the island and producing a large dome within the Pantelleria calderacomplex. The results of the structural analysis carried out on the Island of Pantelleria also improves thegeneral knowledge on the Late Quaternary tectonics of the entire Sicily Channel. ESE–WNW directedextension, responsible for both the tectonic and volcano-tectonic features of the Pantelleria Island, alsocharacterizes, at a greater scale, the entire channel as shown by available geodetic and seismologicaldata. This mode of extension reactivates the older NW–SE trending fault segments bounding the tectonictroughs of the Channel as right-lateral strike-slip faults and produces newNNE trending pure extensionalfeatures (normal faulting and cracking) that preferentially develop at the tip of the major strike-slip faultzones. We thus relate the Late Quaternary volcanism of the Pelagian Block magmatism to dilatationalstrain on the NNE-striking extensional features that develop on the pre-existing stretched area and propagatethroughout the entire continental crust linking the already up-welled mantle with the surface.