Modes of propagation of the compressional deformation in the Umbria-Marche Apennines

Overprinting relationships among major and minor structures in the sedimentary cover of south-eastern Umbria and northern Latium (Central Italy) provide significant information on the modes of compressional deformation propagation in the Umbria-Marche Apennines during the Neogene. The innermost thrust sheets are deformed by outer, younger thrust-related folds: this indicates a progressive migration of compressional fronts towards the east, in a piggy-back thrusting sequence. Jurassic, Cretaceous-Paleogene and Messinian age normal faults within the pre-thrusting template effectively controlled the geometry of the evolving Late Miocene-Early Pliocene compressional features. Locally anomalous younger-over-older relationships along upward-propagating thrust faults are interpreted in the framework of a progressive, rather than multistage, compressional deformation. Structural evidence is effective in reconstructing the kinematic evolution of the fold-and-thrust belt through sequential cross-section restoration.