Late Quaternary tectonics and active ground deformation in the Catania urban area (eastern Sicily): New constraints from a geological investigation Stefano Catalano, Francesco Pavano, Gino Romagnoli, Giuseppe Tortorici ⁎ Dipartimento di Scienze Biologiche, Geologiche e Ambientali – Sezione di Scienze della Terra, Università di Catania, C.so Italia 55, – 95129 Catania, Italy abstract article info Article history: Received 6 March 2017 Received in revised form 24 May 2017 Accepted 29 May 2017 Available online 30 May 2017 New surface and subsurface geological data on the Catania urban area, in eastern Sicily, are here illustrated by a detailed geological map of the city and by four significant cross-sections. Our study aims at defining the prolon- gation of the principal regional Late Quaternary tectonic features, beneath the city. The resulting geometry of the investigated structures completes the tectonic pictures of two different stages of deformation. The earlier struc- tural association, ranging in age from 600 to 125 ka, consists of a transpressive dextral belt that include E-W oblique thrust ramp, located to the south and the north of the city respectively, connected by a wide NE-SW ori- ented anticline crossing the urban area. The younger structural association developed since the Late Pleistocene and includes a set of ENE-trending folds that originated at the hangingwall of a main thrust ramp running just beneath the old town (Catania Thrust Ramp). These contractional features have been active during the last 60 ka and their geometry is consistent with the active ground deformation observed by the available geodetic data (GPS vectors and DInSAR analyses). The entire set of the recent structures are bordered to the north by a dextral transfer zone, reactivating part of the previous E-W alignment, that now represents the tectonic boundary with the Mt. Etna Volcano transtensional domain. Our data suggest that the Catania Thrust Ramp could play a main role in the active deformation pattern of the region, thus representing a potential seismotectonic feature to be carefully investigated for the re-evaluation of the seismic hazard of the area. © 2017 Elsevier B.V. All rights reserved. Keywords: Catania Eastern Sicily Mt. Etna Late Quaternary contractional tectonics Ground deformation Seismic hazard 1. Introduction The city of Catania, (pop. estim. 315,000 in 2016) is located in east- ern Sicily in a seismically active region (Postpischl, 1985; Boschi et al., 1995, 1997), composed of two adjacent Late Quaternary tectonic do- mains (Catalano et al., 2004). To the south, NNW-SSE contraction (Bonforte et al., 2015) is active in the region hosting the NE-trending front of the allochthonous Maghrebian Thrust Belt (Torelli et al., 1998), whereas a WNW-trending active transtension characterizes the Mt.Etna volcano region, to the north (Cocina et al., 1997; Catalano et al., 2004; Palano et al., 2012; Tortorici et al., 2013). A prominent NW- SE oriented dextral transfer zone separates the two Late Quaternary do- mains (Catalano et al., 2004; Azzaro et al., 2013; Barreca et al., 2013) (Fig. 1a). In this region, GPS data and DInSAR analyses (Bonforte et al., 2011; De Guidi et al., 2015) point out impressive active ground deformation in the contractional and transtensional domains as well as dextral dis- placements along the intermediate NW-SE trending transfer zone. In the Catania region, the long-term geological signature of this de- formation is evident immediately to the southwest of the city, where syn-tectonic Late Quaternary marine and continental deposits are wide- ly exposed (Monaco, 1997; Monaco et al., 2002; Catalano et al., 2004). Conversely, in the urban area and in its northeastern outskirts, huge vol- umes of lava flows, emitted from the Mt. Etna volcano, have masked the cumulative tectonic structures, which are imprinted in the sub-volcanic substratum (Catalano et al., 2005). In this paper we discuss a series of detailed geological transects across the city of Catania, portraying the geometry of the sedimentary substratum, the morphological outlines of the sub-volcanic topography and the arrangement of the overlying volcanic covers. This paper is based on the results of the extensive (1:5000 scale) geological mapping of the city of Catania, including the surrounding areas, which was car- ried out for the seismic microzonation of the region. The study was sup- ported by the interpretation of 195 well-logs. The analyzed profiles are located on the prolongation of the main regional tectonic features al- ready described out of the urban area and crosses the main active tec- tonic lineaments evidenced by the geodetic data. The transects have been selected taking into account the number of significant surface and subsurface geological information, useful for reconstructing reliable 2D geometries of the investigated stratigraphic horizons. Tectonophysics 712–713 (2017) 200–207 ⁎ Corresponding author. E-mail addresses: catalano@unict.it (S. Catalano), fpavano@unict.it (F. Pavano), g.romagnoli@unict.it (G. Romagnoli), gtortoric@libero.it (G. Tortorici). http://dx.doi.org/10.1016/j.tecto.2017.05.033 0040-1951/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto