Causes and Consequences of Diachronous V-Shaped Ridges in the North Atlantic Ocean ...

• Main Authors: Parnell-Turner, R, White, N, Henstock, TJ, Jones, SM, Maclennan, J, Murton, BJ
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU) 2017
• Subjects: Iceland plume; V-shaped ridges; mantle convection; oceanic crust; Reykjanes; Iceland; North Atlantic
• Online Access: https://dx.doi.org/10.17863/cam.12669; https://www.repository.cam.ac.uk/handle/1810/274631

AbstractIn the North Atlantic Ocean, the geometry of diachronous V‐shaped features that straddle the Reykjanes Ridge is often attributed to thermal pulses which advect away from the center of the Iceland plume. Recently, two alternative hypotheses have been proposed: rift propagation and buoyant mantle upwelling. Here we evaluate these different proposals using basin‐wide geophysical and geochemical observations. The centerpiece of our analysis is a pair of seismic reflection profiles oriented parallel to flow lines that span the North Atlantic Ocean. V‐shaped ridges and troughs are mapped on both Neogene and Paleogene oceanic crust, enabling a detailed chronology of activity to be established for the last 50 million years. Estimates of the cumulative horizontal displacement across normal faults help to discriminate between brittle and magmatic modes of plate separation, suggesting that crustal architecture is sensitive to the changing planform of the plume. Water‐loaded residual depth measurements are used ...