The Role of Tectonic Inheritance in the Tectonic Evolution and Breakup of the Atlantic and Arctic Oceans
In the more than fifty years since J. Tuzo Wilson posed the question, ‘Did the Atlantic close and then reopen?’, we have come to understand that the continents preserve the tectonic record of multiple superimposed Wilson cycles. From the Central Atlantic to the Arctic, structural lineaments from Proterozoic and Paleozoic orogenies record the closing of earlier oceans. What influence did these inherited orogenic structures exert on the tectonic evolution of the present day North Atlantic and Arctic margins? Continental breakup started in the Jurassic with the opening of the Central Atlantic and propagated northwards to the Eurasia Basin. We show that a palinspastic deformable margin plate kinematic model that has in some areas quantitatively restored up to several hundred kilometers of Mesozoic-Cenozoic extension provides a valuable analytical tool that enables us to examine pre-existing structures and their role in break-up including: the evolution and orientation of rifting events; the reactivation of sutures and thrust fronts; the interplay between sutures of various ages; and the activation of major transforms from pre-existing sutures. This type of plate model provides a valuable analytical tool that can be used to show the temporal and spatial relationship between pre-existing orogenic structures, evolving rift axes and global plate reorganization events. This provides us with a pre-rift restoration of the Proterozoic and Paleozoic terranes and structural lineaments on the conjugate margins that helps us to analyse their relationship to evolving rift axes and global plate reorganization events through time. Advances in deformable plate reconstruction methods provide us with accurately restored pre-breakup margin geometry, more detailed restored and reconstructed basement and structure maps, and the history of lateral strain and crustal thinning across these margins. Interpretation of these modelling results has led to a clearer understanding of the relationship between inherited structural features and their control on rifting, break-up history and basin development.
AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019