Structural evolution of the superimposed Provençal and Subalpine fold-thrust belts (SE France)

Early onset of Pyrenean collision (97–90 Ma) evidenced by U–Pb dating on calcite (Provence, SE France)

“…We provide structural evidence to interpret the most significant exhumation phase as a result of compressional deformation and not only extension as is generally proposed in the recent literature. This Exhumed mantle complete geological history (Balansa et al, 2022). Additionally, halokinetic processes are thought to have had a significant influence on the structural evolution of Provence (Célini et al, 2020).…”

“…Classically, the main phase of shortening in the Provence domain is named the Pyrenean-Provence compression and is attributed to the Campanian-Eocene period in relation to collisional and subduction processes occurring along the Sardinia-Corsica boundary of Eurasia (Figure 1; e.g., Balansa et al, 2022;Lacombe & Jolivet, 2005).…”

“…(2) a second phase, known as the 'Pyrenean-Provençal' phase, has been given a variable time span but is usually accepted as having occurred between the Late Cretaceous and the early late Eocene (i.e. pre-Priabonian: e.g., Caby, 1973;Debrand-Passard et al, 1984;Siddans, 1979;Ford, 1996;Espurt et al, 2019;Balansa et al, 2022).…”

Cross-propagation of the western Alpine orogen from early to late deformation stages: Evidence from the Internal Zones and implications for restoration

“…The sedimentary cover is locally involved in 133 thin-skinned fold and thrust deformation of different ages and orientations due to 134 Pyrenean and Alpine contractional propagation (Gidon, 1997;Philippe et al, 1998;135 Espurt et al, 2012;Schwartz et al, 2017). The occurrence of soft evaporitic Triassic 136 layers played a major control on the location of detachments (Lickorish et al, 2002;137 Espurt et al, 2019;Balansa et al, 2022). Remnants of synorogenic basins record 138 different stages of propagating lithospheric flexure through foreland basin and 139 forebulge development, with flysch and molasse deposition (Joseph & Lomas, 2004; 140 Ford & Lickorish, 2004;Kempf & Pfiffner, 2004;Schwartz et al, 2012;Kalifi et al, 2020).…”

“…60 This complex 3D and polyphase deformation history makes the initial architecture of the 61 precursor continental margin, presently involved in the western Alpine arc difficult to 62 restore, particularly because the most prominent structures which define the present-63 day trend of the arc probably postdate the initial contractional features as they 64 overprint the evidence of the earliest orogenic propagation developed during Eocene 65 times. Moreover, the Adria plate first collided with terranes connected to the eastern 66 Iberia plate, such as the Briançonnais domain (Stampfli et al, 2002;Handy et al, 2010), 67 so that an early part of the convergence history is likely to have been accommodated by 68 oblique contraction and reactivation along the original eastern extent of the Pyrenean 69 orogen, resulting in complex interference between pre-existing Pyrenean structures and 70 newly evolving Alpine deformation (Lacombe & Jolivet, 2005; Schreiber et al, 2011; 71 Balansa et al, 2022). Finally, the Alpine structures have experienced more recent 72 fragmentation, in the southern part of the arc, through the development of the Ligurian 73 and Tyrrenian breakups and by the growth of the Apenninic chain, driven by the 74 complex lithospheric motion of various lithosphere slabs Zhao et al, 75 2016;Salimbeni et al, 2018).…”