PT - JOURNAL ARTICLE AU - Smallwood, J. R. AU - White, R. S. AU - Minshull, T. A. TI - Sea-floor spreading in the presence of the Iceland plume: the structure of the Reykjanes Ridge at 61°40′N AID - 10.1144/GSL.JGS.1995.152.01.24 DP - 1995 Nov 01 TA - Journal of the Geological Society PG - 1023--1029 VI - 152 IP - 6 4099 - http://jgs.lyellcollection.org/content/152/6/1023.short 4100 - http://jgs.lyellcollection.org/content/152/6/1023.full SO - Journal of the Geological Society1995 Nov 01; 152 AB - 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.