A reconstruction of Iberia accounting for W-Tethys/N-Atlantic kinematics since the late Permian-Triassic

Abstract

Abstract. The West European kinematic evolution results from the opening of the West Neotethys and the Atlantic oceans since the late Paleozoic and the Mesozoic. Geological evidence shows that the Iberian domain well preserved the propagation of these two rift systems and is therefore key to significantly advance our understanding of the regional plate reconstructions. The Late Permian-Triassic tectonic evolution of Iberian rift basins shows that they have accommodated significant extension, but this tectonic stage is often neglected in most plate kinematic models, leading to the overestimation of the movements between Iberia and Europe during the subsequent Mesozoic (Early Cretaceous) rift phase. By compiling existing seismic profiles and geological constraints along the North Atlantic margins, including well data over Iberia, as well as recently published kinematic and paleogeographic reconstructions we propose a coherent kinematics model of Iberia that considers both the Neotethyan and Atlantic evolutions. Our model shows that the Europe-Iberia plate boundary was a domain of distributed and oblique extension made of two rift systems, in the Pyrenees and in the Iberian intra-continental basins. It differs from standard models that consider left-lateral strike-slip movement localized only in the northern Pyrenees in introducing a significant strike-slip movement south of Ebro accounting for Late Permian-Triassic extension and by emphasizing the need for an Ebro microcontinent. At a larger scale it emphasizes the role played by the late Permian-Triassic rift and magmatism, as well as strike-slip faulting in the evolution of the western Neotethyan Ocean and their control on localization of the Atlantic rift.

Lateral variations of pressure-temperature evolution in non-cylindrical orogens and 3-D subduction dynamics: the Betic-Rif Cordillera example

“…The palaeo-thermal structure in the HT-metamorphism zone in the Nieves Unit showing an obliquity of isograds with the contact also reinforces our extensional emplacement model. The proposed extensional setting with mantle exhumation fits the observations of Pedrera et al (2020) with sheared peridotite bodies embedded in Triassic sediments and is similar to what is generally expected from the pre-orogenic setting of the Betics corresponding to a former oblique and segmented system between the Central Atlantic and the Western Tethys (Leprêtre et al, 2018;Fernàndez et al, 2019;Angrand et al, 2020;Pedrera et al, 2020).…”

Tectono‐Stratigraphic and Thermal Evolution of the Western Betic Flysch: Implications for the Geodynamics of South Iberian Margin and Alboran Domain

“…Rifting during late Triassic to early Jurassic between central Atlantic and Alpine Tethys and during late Jurassic to early Cretaceous times (Angrand et al, 2020;Dercourt et al, 1986;Handy et al, 2010;Labails et al, 2010;Leprêtre et al, 2018;Martín-Algarra, 1987) led to the formation of several basins between Africa and Iberia. They correspond to the Subbetic (e.g., Crespo-Blanc & de Lamotte, 2006;Jabaloy-Sánchez et al, 2019), the Algarve basin (e.g., Ramos et al, 2016), the Cretaceous flysch basin, stretching along the transform plate boundary between Africa and Iberia, and the external Rif and Ketama basins (Durand- Delga, 1972;Wildi, 1983).…”

Nature, Origin, and Evolution of the Pyrenean‐Cantabrian Junction

“…The occurrence of a major transfer fault at the Pyrenean‐Cantabrian junction suggests a decoupling of these two realms during Mesozoic rifting and Cenozoic convergence, and raises questions about where and how major structural units terminate laterally (e.g., rift basins, orogenic slab). It also questions the general kinematics and/or location of the Iberia‐Ebro‐Europe plate boundaries (Figure 1b; e.g., Angrand et al., 2020; Nirrengarten et al., 2018; Tavani et al., 2018; Tugend et al., 2015). These recent geodynamic models involving a continental block (Ebro) in between the classical Iberia‐Europe plate boundary have been proposed to solve some of the geometric and kinematic issues involved by the counter‐clockwise rotation and the lateral displacement of the Iberian plate along a single, localized plate boundary.…”

“…One model involves a pure E‐W strike‐slip displacement, of up to 400 km, leading to the formation of pull‐apart basins (Figures 1b and 1c, left inserts; Canérot, 2017; Choukroune & Mattauer, 1978; Choukroune, 1992; Oliva‐Urcia et al., 2010), suggesting that the NE‐SW striking structures such as the Pamplona fault might correspond to basin‐bounding faults. The opposite model proposes orthogonal, N‐S extension from Late Aptian onwards that post‐date a yet poorly defined Late Jurassic‐Early Cretaceous transtensional phase (Angrand et al., 2020; Tugend et al., 2015). In this scenario, the Pamplona fault would correspond to either a sharp (e.g., Rat, 1988; Tugend et al., 2015) or soft (Roca et al., 2011) transfer zone, segmenting and transferring the deformation between the Mauléon and the Basque‐Cantabrian basins (Figures 1b and 1c, right inserts).…”