Investigating the role of Iberia and its interplay with the Newfoundland and Irish offshore margins using plate reconstructions
The tectonic evolution of the southern North Atlantic is a subject of increasing interest due to its continental margins playing host to several world-class frontier regions for oil and gas exploration. The Newfoundland-Iberia conjugate margin pair serves as one of the best studied non-volcanic rifted conjugate margin pairs in the world, and is a topic of constant scientific debate due to its complex plate kinematic history and geological evolution. Recent adaptability of the GPlates freely available plate tectonic reconstruction software provides an excellent tool for gaining insight into complex plate kinematic problems. The ability to account for regions of deformation, integration of various geological and geophysical datasets, and the ability to calculate temporal variations in crustal thickness, strain rates, and velocity vectors provide an optimal environment for solving crustal-scale geological and geophysical problems. Building upon previous rigid and deformable plate tectonic modelling studies, the aim of this work is to create deformable plate tectonic models of Iberia with emphasis on the West Iberian margin and the Pyrenees to assess Iberia's evolution during the formation of the southern North Atlantic from 200 Ma to present day. A comparison of crustal thickness results calculated from GPlates models with those obtained from gravity inversion, passive and controlled source seismology, and geological field mapping, provided a good metric for investigating the plate kinematics of Iberia and assessing previous discrepancies when considering the crustal evolution of the West Iberian margin and the Pyrenees as an integrated plate kinematic system. Results from the GPlates models produced in this study also demonstrate the significance of continental fragments and their independent motion during rifting. In particular, we investigate the independent motion of the Galicia Bank and its role with respect to the deformation experienced within the Galicia Interior Basin and the role of the Ebro Block and Landes High during deformation prior to the Pyrenean Orogeny. In addition, this study highlights the importance of inherited structures with respect to the styles of deformation experienced during rifting of continental crust. Preliminary deformable plate modeling results of the West Iberian margin indicate that the independent motion of the Galicia Bank and its interplay with inherited structures is crucial for deriving the amount of deformation inferred by gravity inversion and regional seismic studies within the Galicia Interior Basin.