The Iberian microcontinent and its connected oceanic crust are affected by deformations related to the Eurasian‐African plate boundary. Active stress inversions from populations of moment tensor focal mechanisms have been performed around and inside the Iberian peninsula, using a total of 213 moment tensor estimates. Main results are as follows: (1) The tensorial solutions show better consistency and lower misfits compared to those obtained previously from first P arrival focal mechanisms. (2) Along the Eurasia‐Africa western boundary, the type of active stresses progressively changes easternward from triaxial extension to uniaxial compression along the Terceira Ridge, the Gloria Fault zone, and the Gulf of Cadiz. (3) In the Betics‐Alboran‐Rif zone, uniaxial extension predominates with Shmax N155°E trending. (4) In northern Algeria, uniaxial compression reappears. (5) The Iberian foreland is currently under strike‐slip to uniaxial extension tensorial conditions.

The Iberian Chain is a wide intraplate deformation zone formed by the tectonic inversion during the and basin evolution analysis, macrostructural Bouguer gravity anomaly analysis, detailed mapping and paleostress inversions have been used to prove the important role of strike slip deformation. In addition, we demonstrate that two main folding trends almost perpendicular (NE SW ID E W artd NW SE) were simultaneously active in a wide transpressive zone. The two fold trends were generated by different mechanical behaviour, induding buckling and bending under constrictive strain conditions. We propose that strain partitioning occurred with oblique compression and transpression during the Cenozoic.

[1] Inferences from analogue models support lithospheric folding as the primary response to large-scale shortening manifested in the present day topography of Iberia. This process was active from the late Oligocene-early Miocene during the Alpine orogeny and was probably enhanced by reactivation of inherited Variscan faults. The modeling results confirm the dependence of fold wavelength on convergence rate and hence the strength of the layers of the lithosphere such that fold wavelength is longest for fast convergence rates favoring whole lithosphere folding. Folding is associated with the formation of dominantly pop-up type mountain ranges in the brittle crust and thickening of the ductile layers in the synforms of the buckle folds by flow. The mountain ranges are represented by upper crustal pop-ups forming the main topographic relief. The wavelengths of the topographic uplifts, both, in model and nature suggest mechanical decoupling between crust and mantle. Moreover, our modeling results suggest that buckling in Iberia took place under rheological conditions where the lithospheric mantle is stronger than the lower crust. The presence of an indenter, inducing oblique shortening in response to the opening of the King's Trough in the north western corner of the Atlantic Iberian margin controls the spacing and obliquity of structures. This leads to the transfer of the deformation from the moving walls towards the inner part of the model, creating oblique structures in both brittle and ductile layers. The effect of the indenter, together with an increase on the convergence rate produced more complex brittle structures. These results show close similarities to observations on the general shape and distribution of mountain ranges and basins in Iberia, including the Spanish Central System and Toledo Mountains.

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