<scp>3D</scp> Quantification of Subsidence During Pyrenean Retro‐Wedge Initiation: Role of Structural and Thermal Inheritance on Hyperextended Margin Inversion (Aquitaine Basin)

ABSTRACT We present novel 3D subsidence data enabling vertical movements' quantification during the early formation of the Pyrenean retro‐wedge. From Cenomanian to Turonian times, subsidence is relatively low (~26 ± 10 m/Myr), corresponding to a brief 10 Myr thermal re‐equilibration of the European lithosphere following the hyperextended rift episode. The Coniacian–Santonian period marks a major subsidence reorganisation, with uplift or subsidence cessation on the former Early Cretaceous margin and a sudden acceleration in the necking domain (~300 ± 10 m/Myr). We interpret this episode as lithospheric buckling related to far‐field deformation leading to superimposed flexural and thermal subsidence due to incomplete thermal re‐equilibration. During Campanian–Maastrichtian time, subsidence decreases in the necking domain (~26 ± 10 m/Myr) and resumes on the margin (~26 ± 10 m/Myr), reflecting a homogenization of subsidence drivers across the Aquitaine Basin. This marks the progressive shift from post‐rift thermal subsidence to flexural retro‐foreland basin subsidence.