A new kinematic model of the Mid-Atlantic Ridge between 55 degrees 55 ' N and the Bight Transform Fault for the past 6Ma

摘要

We present a new fine-scaled tectonic model of the Mid-Atlantic Ridge between 55 degrees 55'N and the Bight Transform Fault for the past 6Ma. We model our new marine magnetic data, providing a robust kinematic model for the area. The new model uses propagating rifts to explain observed asymmetry in high-resolution marine magnetic data. The area closest to the Bight Transform Fault has undergone two relatively large (9km and 6km) relocations of the spreading center within the past 1Ma, which explains the divided central anomaly; we attribute this relocation to two very fast propagations. The amount of lithosphere transferred between the plates during each propagation event is 2-10km, and the propagators identified are short-lived (0.5-4.0Ma). Most of the propagation in the area is to the north, and all but two propagators transfer lithosphere from the Eurasian plate to the North American plate, which is consistent with the overall eastward relocation of the Reykjanes Ridge.