Tectonics and sedimentation within a messinian foredeep in the Central Apennines, Italy.

The Marche-Abruzzi thrust system is part of the Central Apennine fold-and-thrust belt of mainland Italy. Our study area covers the SE portion of the Umbria-Marche-Abruzzi region and the northern part of the Gran Sasso Mountains. A thick pile of turbidites is exposed in this area; they were deposited within a Messinian foredeep in front of the evolving fold-and-thrust belt. We have used regional structural interpretations together with unpublished well-log and seismic data to construct a cross-section across the external portion of the thrust system. Our work suggests that: (i) deformation of the sediments in the Messinian foredeep began shortly after their deposition, and continued until the late Pliocene; (ii) the restored (pre-deformation) width of the basin was approximately twice that of the present-day basin, and the depocentre migrated eastwards at a rate of about 4 cm/yr; (iii) the geometry and physiography of the Messinian foredeep were controlled by a number of longitudinal and transverse structural features which may be related to foreland ramp activity or to differential flexuring of the Apulian lithosphere, respectively.