Geological and geodetic constraints on the active deformation along the northern margin of the Hyblean Plateau (SE Sicily)

Abstract

A geologic and geodetic integrated analysis of the northern margin of the Hyblean Plateau (SE Sicily) has been carried out in order to test the relationship between the active deformation, recorded by GPS data, and the long-term tectonic evolution, reconstructed by the interpretation of structural and morphological data. Our study revealed the active growth of a large antiform, as a consequence of the positive tectonic inversion of the previous flexure, bordering the Hyblean Foreland. The deformation of Middle–Late Pleistocene marine terraces and the evolution of the drainage system are consistent with a progressive regional tilting of the entire eastern sector of the Hyblean Plateau (Siracusa Domain), representing the southern limb of the active antiform. The geometry of the Late Quaternarymarine strandlines, comparedwith the results of analoguemodels, is compatible with the effects of the NW-ward propagation of a detachment fault at depth. The active deformation of the Hyblean region, coherentwith the Nubia–Eurasia plate convergence, suggests to candidate the inverted tectonics at the northern border of the Hyblean Plateau as potential seismogenic sources of the area.