Stratigraphic versus structural control on the deformation pattern associated with the evolution of the Mt. Catria anticline, Italy S. Tavani a, * , F. Storti a , F. Salvini a , C. Toscano b a Dipartimento di Scienze Geologiche, Universita ` degli studi ‘‘Roma Tre’’, Rome, Italy b E&P Division, ENI S.p.A., San Donato Milanese, Italy Received 1 March 2007; received in revised form 29 January 2008; accepted 30 January 2008 Available online 8 February 2008 Abstract The evolution of deformation patterns during thrust-related folding is of importance for both industrial and academic purposes because of the control that it exerts on the migration and accumulation of fluids in reservoirs. The link between structural position and deformation pattern has been described in both theoretical and field works. On the other hand, the well-documented dependence of deformation structures on the me- chanical rock properties and on the environmental conditions indicates that, during folding, structural, stratigraphic, and environmental variables interact to control the deformation pattern within folds. In this work we describe the deformation pattern of the Mt. Catria anticline (Northern Apennines, Italy) and we investigate its variability with (1) the across-strike structural position, and (2) the rock type in the same structural position. Point (1) allowed us to identify and use the syn-folding deformation structures to constrain the fold kinematics. The result of point (2) analyses allowed us to divide the exposed Umbro-Marchean multilayer into three major mechanical units characterised by specific deformation mechanisms and patterns. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Thrust-related folding; Brittle deformation analysis; Mechanical stratigraphy; Cross-section balancing; Northern Apennines 1. Introduction Fold kinematics play a primary role in determining the type, frequency, and attitude of folding-related deformation structures in fault-related folds (e.g. Dahlstrom, 1990; Fischer et al., 1992; Storti and Salvini, 1996; Cardozo et al., 2005; Tavani et al., 2006a). These deformation structures in turn exert a first-order influence on the migration and accumulation of fluids in reservoirs within thrust wedges (e.g. Cooper, 1992; Gholipour, 1998; Van Dijk et al., 2000). Because of this, a va- riety of studies have attempted to provide criteria for predict- ing folding-related deformation patterns from numerical (e.g. Erickson and Jamison, 1995; Strayer and Suppe, 2002; Salvini and Storti, 2004), analogue (e.g. Chester et al., 1991), and geometrical (e.g. Sanderson, 1982; Hedlund et al., 1994; Storti and Salvini, 1996; Salvini and Storti, 2001) modelling. These studies suggested that structural (i.e. geometrical and kinemat- ical) variables control the final deformation pattern in the fold. Accordingly, its study can provide an additional tool for con- straining the kinematics of natural folds (e.g. Thorbjornsen and Dunne, 1997). On the other hand, the well-documented dependence of folding-related deformation structures on the mechanical stratigraphy (e.g. Corbett et al., 1987; Woodward and Rutherford, 1989; Protzman and Mitra, 1990; Gross, 1995; Couzens and Wiltschko, 1996; Fischer and Jackson, 1999; Chester, 2003; Di Naccio et al., 2005) and environmen- tal conditions (e.g. pressure, temperature, water circulation) during folding (e.g. Chester et al., 1991; Jamison, 1992; Lemiszki et al., 1994), indicates that the study of deformation pattern must also include stratigraphic and environmental variables. In this paper, we describe the structural and stratigraphic in- fluences on the deformation pattern in the Mt. Catria anticline * Corresponding author: Departament de Geodinamica i Geofisica, Facultat de Geologia, Universitat de Barcelona, c/ Marti Franques s/n, 08028 Barce- lona, Spain. Tel.: þ34 93 403 5957. E-mail address: stefano.tavani@ub.edu (S. Tavani). 0191-8141/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.jsg.2008.01.011 Journal of Structural Geology 30 (2008) 664e681 www.elsevier.com/locate/jsg