Acknowledgements and Funding We are grateful to Ente Minerario Siciliano and Italkali for the provision of extensive subsurface data from Realmonte, Corvillo and Mandre areas. We thank F. Peel and an anonymous referee for comments. Seismic reflection data are available for inspection and interpretation at the Virtual Seismic Atlas (www. seismicatlas.org). R.M. acknowledges a MIUR Cofin-PRIN 2010–2011 grant.Peer reviewedPublisher PD