Map of seafloor from the paper.
An updated seafloor age map and newly mapped fractures in the North Atlantic Ocean, along the axis of the Reykjanes Ridge south of Iceland. Contours, based on updated magnetic anomaly measurements, are annotated in MY (millions of years). The dashed line marks the 0 MY contour and follows the axis of the Reykjanes Ridge to the north and Mid-Atlantic Ridge to the south of the Bight FZ. Credit: Thorhallsson et al. [2024], Figure 4
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Journal of Geophysical Research: Solid Earth

The slow-spreading Reykjanes Ridge overlies the Iceland hotspot in the North Atlantic and its structure records multiple plate boundary reorganizations over the past ~53 million years. Thorhallsson et al. [2024] present a new compilation of shipboard magnetic anomaly and an updated seafloor age map to investigate the evolution and structure of the plate boundary. This work takes a new approach by analyzing the relative motion of individual spreading segments to track the history of breakup and reassembly of the Reykjanes Ridge.

The authors find that Reykjanes Ridge is well-organized and linear, with distinct magnetic anomalies and fracture zones. This structure is derived from interaction of the hotspot and spreading center, in which the hotspot forms melting gradients along the spreading axis, with directivity controlled by a linear, deeper zone of mantle melting. A key contribution of this work is the broad spatial and temporal view of ridge-hot spot interaction, allowing the authors to address a persistent question in plate tectonic theory concerning plate boundary segmentation and evolution.

Citation: Thorhallsson, D., Martinez, F., Hey, R., & Höskuldsson, Á. (2024). Kinematics of the Reykjanes Ridge: Influence of the Iceland hotspot on plate boundary evolution. Journal of Geophysical Research: Solid Earth, 129, e2023JB027319. https://doi.org/10.1029/2023JB027319

—Lindsay Lowe Worthington, Associate Editor, JGR: Solid Earth

Text © 2024. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.