A reconstruction of the North Atlantic since the earliest Jurassic

Abstract

The stretched continental margins of the North Atlantic region record a plate kinematic history dominated by major episodes of extension since the Late Palaeozoic. Accounting for the restoration of this stretched continental crust across the region, and the subsequent derivation of plausible full-fit configurations between these continents, prior to extension, still remains unresolved. Previous plate reconstructions have highlighted difficulties such as determining the amount of extension to be distributed across the multiple episodes of rifting, or defining the distribution of extension across intraplate deformation occurring adjacent to the rifting of two major continents. Here, we implement a new approach to derive a set of total reconstruction poles based on a full-fit, palinspastic restoration of the conjugate margins that considers the rifting evolution of the North Atlantic in a regional plate kinematic context since the Earliest Jurassic. Gravity inversion forms the basis of our regional crustal thickness estimates, and aids in the identification of thinned continental crust. Our crustal restoration estimates are computed in multiple phases along margin segments in accordance with the timing of their major rifting episodes. Our model predicts a full-fit, prerift, palaeogeographic position of all the major continents across the North Atlantic; and predicts a time-dependent evolution of multiple phases of extension including regional divergence directions, consistent with previous observations. Our plate model represents a new approach to plate kinematic reconstructions incorporating the application of a multiphase restoration methodology applied in a major regional context, constrained by the synthesis of several different geological and geophysical data sets.

Kinematic Evolution of the Southern North Atlantic: Implications for the Formation of Hyperextended Rift Systems

“…This method is, however, not valid for magma‐rich margins (e.g., Hatton Bank margin) since they present numerous magmatic additions, corresponding to new crust formation and consequently to a gain in crustal volume. In magma‐rich margins restorations can only be undertaken if the volume of the magmatic additions can be estimated to determine a pseudo RECC (Barnett‐Moore, Müller, et al, ).…”

“…These basins are not the focus of this study, but the position of Greenland has to be constrained to determine the position of Eurasia relative to North America. For this, we rely on the recent restoration of Barnett‐Moore, Müller, et al (). The oceanic evolution of these basins started in Maastrichtian or Paleocene time prior to Chron C27 (61 Ma) and ended at the Eocene‐Oligocene boundary (33 Ma) (Oakey & Chalmers, ).…”

“…However, they only use two rotation poles, one at full fit and the second at the first magnetic anomaly, assuming therefore a continuous evolution during rifting. Intermediate rotation poles are sometimes proposed for rift systems interrupted by tectonic quiescence (Barnett‐Moore, Müller, et al, ). Methodological improvements on the determination of spatiotemporal markers are needed to model both the rifting and the early stages of seafloor spreading.…”

Oblique rifting: the rule, not the exception

“…Opening of the Labrador Sea and rifting between Greenland and Europe competed for many tens of million years (Dickie et al, 2011;Hosseinpour et al, 2013;Barnett-Moore et al, 2016) before the present-day North East Atlantic mid-ocean ridge 10 formed in Eocene times (Gernigon et al, 2015;Gaina et al, 2017) possibly due to the arrival of the Iceland hotspot (Coffin and Eldholm, 1992;Storey et al, 2007). Final separation between Greenland and Europe took place along the sheared margin of the Fram Strait in Miocene times ~17-15 Ma (Jakobsson et al, 2007;Knies and Gaina, 2008).…”

Unraveling the Mesozoic and Cenozoic Tectonothermal Evolution of the Eastern Basque‐Cantabrian Zone–Western Pyrenees by Low‐Temperature Thermochronology

“…For that reason, it has attracted the interest of numerous international research groups, with large geological/geophysical projects developed particularly during the last decade (Topo‐Iberia, Topo‐Europe PYRTEC, Pyramid, Pyrope, Orogen, and RGF‐BRGM, among others). The Pyrenean‐Cantabrian mountain belt is also a key region to place constraints on kinematic models for Iberia, a topic that has been strongly discussed recently (e.g., Barnett‐Moore et al, , , ; Nirrengarten et al, ; van Hinsbergen et al, ). Discriminating between the different kinematic models requires good temporal constraints on the different phases of the tectonic evolution of the Pyrenean‐Cantabrian‐Bay of Biscay system.…”