Sea-floor spreading in the presence of the Iceland plume: the structure of the Reykjanes Ridge at 61°40′N

J. R. Smallwood, R. S. White and T. A. Minshull
Journal of the Geological Society, 152, 1023-1029, 1 November 1995, https://doi.org/10.1144/GSL.JGS.1995.152.01.24

Abstract

We present results from a combined normal incidence and wide-angle seismic survey of the Reykjanes Ridge at 61°40′N in the North Atlantic. The seismic data show that the crust is 8.4–10.0 km thick on the ridge axis. We attribute this thicker than normal oceanic crust to a high degree of melting caused by hot mantle from the Iceland plume beneath the speading centre. Layer 2A of the oceanic crust is significantly thicker at 0 Ma than in crust of age 4 Ma. Our results, combined with other seismic data from the North Atlantic, show that the crustal thickness decreases away from the plume centre to normal oceanic crustal thickness at a distance of approximately 1000 km.

Keywords

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