On the delayed expression of mantle inheritance–controlled strain localization during rifting

Abstract

In this paper, we explore the relative impact mantle inheritance can have on the evolution of magma-poor rift systems during the early stages of rift localization. To this end, we revisit the tectonic history of the Mesozoic Northeast Atlantic and its North Sea subdomain, analyzing these observations through comparison with results from recent analogue tectonic modeling work. Our analysis suggests that initial broadly distributed rift basin formation may be controlled by crustal inheritance, whereas the subsequent localization of deformation along deeper mantle inheritance may have caused the overprinting of previous rift basin trends in the Northeast Atlantic. This overprinting became possible as soon as the thinning of the ductile crust during progressive rifting allowed for sufficient coupling between the mantle and the upper crust. Importantly, we suggest that no changes in plate motion direction due to large-scale reorganization of the plate tectonic system are needed for differently oriented basin trends overprinting each other to develop. With these insights, we propose an updated scenario for rift kinematics in the North Sea involving continuous E-W plate divergence and provide a framework to rethink the evolution of other rift systems around the world during their early stages of rift localization.