A closing Ligurian Sea?

Structure and evolution of a passive margin in a compressive environment: Example of the south-western Alps–Ligurian basin junction during the Cenozoic

“…Pulses in the deformation occurred in the Argentera massif at w11 Ma, and then at w6 and 3.5 Ma (Bigot-Cormier et al, 2000;Foeken et al, 2003), that may have propagated down to the deep margin during the Pliocene (Bigot-Cormier et al, 2004;Foeken et al, 2003). Finally, the current regional seismicity reveals a present-day strike-slip state of stress in the Nice subalpine chain (Baroux et al, 2001;Courboulex et al, 2001Courboulex et al, , 2007 and a compressional state of stress in the deep Ligurian basin (Augliera et al, 1994;Béthoux et al, 1992Béthoux et al, , 2008Courboulex et al, 1995;Larroque et al, 2009). The causes of this recent deformation are still a matter of debate and may be related to Alpine compression and/or to gravitational spreading of the Alps toward the Ligurian basin (e.g.…”

Vertically stacked Gilbert-type deltas of Ventimiglia (NW Italy): The Pliocene record of an overfilled Messinian incised valley

“…crustal compression, whose effects are seen both onshore and offshore. Onshore, reverse faults with focal depth from 5 to 15 km reveal a compressional deformation in the deeper part of the crust (Béthoux et al, 1993). Geomorphological studies indicate a general uplift of the Ligurian coast, that increases eastwards from Nice (Clauzon et al,1996b;Dubar and Guglielmi, 1997), and fission-track data on apatites suggest a major phase of uplift of the Argentera Massif ( Fig.…”

The GROSMarin experiment: three dimensional crustal structure of the North Ligurian margin from refraction tomography and preliminary analysis of microseismic measurements

“…Geodesy shows some shortening of less than 1 mm/yr between Corsica and the Ligurian coast and also between this coastal area and the axial zone of the southwestern Alps . Two candidates have been proposed to explain this deformation: a local cause is the strong altimetric gradient between the Argentera massif and the deep basin, which would result into downhill gravity collapse whereby strain would focus on structures between the axial Alpine zone and the toe of the North Ligurian margin [Béthoux et al, 2008]; the alternative explanation implies the broader scale convergence motion between Africa and Eurasia, some residual part of which would be accommodated on the margin and lead to its compressive reactivation , possibly through the differential motion of the Apulian block [Béthoux et al, 1992;Calais et al, 2002].…”