Investigating the Plate Kinematics of the Bay of Biscay Using Deformable Plate Tectonic Models

Abstract

The plate kinematic evolution of the Bay of Biscay during rifting and subsequent opening of the southern North Atlantic (Figure 1a) has been a subject of debate for several decades (

Advances in Deformable Plate Tectonic Models: 2. Reconstructing the Southern North Atlantic Back Through Time

“…The deformable plate modeling approach originally presented in the companion contribution of this study (Part 1) permits the crustal evolution of the southern North Atlantic to be studied in detail. In contrast to previously published deformable plate models of the southern North Atlantic (King et al., 2020, 2021; Peace, Welford, et al., 2019; Yang et al., 2021), the models presented herein allow for the pre‐Jurassic crustal structure, the strain partitioning within continental blocks, and the evolution of proximal rift domains to be visualized and investigated. Furthermore, the results of this study demonstrate the potential role played by both inherited structures and continental blocks during rifting.…”

“…Furthermore, in addition to recent rigid plate kinematic studies of Iberia that incorporate continental blocks (Angrand et al., 2020; Angrand & Mouthereau, 2021; Frasca et al., 2021), deformable plate models have proven to be advantageous for investigating the interplay between plate kinematics and deformation (Ady & Whittaker, 2018; Müller et al., 2019; Peace, Welford, et al., 2019). With respect to Iberia, recent deformable plate modeling studies highlight the impact of continental blocks on the deformation and crustal thickness evolution of the West Iberian margin (King et al., 2020) and Bay of Biscay (King et al., 2021), emphasizing that their inclusion can mitigate perceived discrepancies related to the plate kinematics of Iberia itself. As a result, a combination of deformable plate models (King et al., 2020, 2021) and rigid plate reconstruction studies focused on the kinematics and evolution of continental blocks (Angrand et al., 2020; Angrand & Mouthereau, 2021) now provide a clearer kinematic link between the kinematics of Iberia and its surrounding margins throughout the southern North Atlantic.…”

Advances in Deformable Plate Tectonic Models: 1. Reconstructing Deformable Continental Blocks and Crustal Thicknesses Back Through Time

“…The use of rigid continental blocks, such as the Flemish Cap and Porcupine Bank, within deformable plate models has proven to be useful for studying the complex kinematics and crustal thickness evolution of offshore rifted margins throughout the southern North Atlantic Ocean (King et al., 2020, 2021; Peace et al., 2019; Yang et al., 2021). However, the majority of previously published deformable plate models are carried out using several assumptions that are often geologically insufficient.…”

“…To our knowledge, all deformable plate models published to date using the GPlates software have been carried out using a constant crustal thickness assumption at an initial time frame of interest. For example, many of the previously published deformable plate models of the North Atlantic assume a 30 km crustal thickness estimate prior to the beginning of significant rifting, approximately 200 Ma (Peace et al., 2019; King et al., 2020, 2021). However, despite this assumption being adequate in previous studies investigating regional plate kinematics and deformation, crustal thicknesses are likely to be highly variable at model start times due to previous tectonic events not considered within the time frame of a model.…”

“…Deformable plate tectonic models are becoming an increasingly used method for studying plate kinematics and temporal variations in strain rate and crustal thickness (Peace, 2021). Recently, deformable plate models have been used to investigate the interplay of deformation and plate kinematics throughout the North Atlantic (King et al., 2020, 2021; Peace et al., 2019; Yang et al., 2021), and other regions abroad (Cao et al., 2020; Flament et al., 2014; Müller et al., 2019). Despite their ability to more diligently assess the kinematics of microplates, continental blocks, and temporal variations in crustal thickness, the majority of previously published deformable plate modeling studies depend on numerous assumptions that can be geologically unsatisfying.…”