Barra Fan: a major glacial depocentre on the western continental margin of the British Isles

The Barra Fan is a large prograding sedimentary wedge of Pliocene–Pleistocene age that has built out into the deep-water basin of the Rockall Trough west of Britain (Holmes et al. 1998). Together with the Donegal Fan, considered to be part of the same fan complex, it covers an area of about 7000 km2 (Armishaw et al. 2000) and locally approaches 700 m in thickness. The bulk of the sediments are thought to be glacially derived from the British Ice Sheet, with ice flowing from northern Ireland and western Scotland converging to reach the shelf edge between 56° N and 57° N via several cross-shelf troughs, most recently at c. 29–27 ka cal BP (Dunlop et al. 2010).