The structure of King's Trough, Northeast Atlantic, from bathymetric, seismic and gravity studies

Abstract

Summary. We present new seismic and gravity data from the linear chain of deeps and flanking ridges known collectively as King's Trough, and combine them to produce crustal models of the western end of the complex. These models show that there is an abnormally low-velocity , low-density crust under the trough itself, and that the whole King's Trough feature is situated in a region of slightly thicker than normal oceanic crust. The flanks and basins of King's Trough are not in local isostatic equilibrium, although the feature now appears to be inactive. We believe these data indicate a history of extension and of hot-spot activity at King's Trough, and that the feature was formed either as a slow-spreading arm of an R-R-R triple junction associated with a Mid-Atlantic Ridge hot-spot, or by subsequent rifting of a preexisting hot-spot trace.