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Department of Geology, Royal Holloway University of London, Egham, TW20 0EX, UK
The West Shetland Shelf (WSS) is part of a carbonate province ranging through 11° of latitude on the western seaboard of the British Isles. Bioclastic gravels and sands and quartzitic shelly sediments, ranging in thickness from a few centimetres to 2 m have been accumulating since the Flandrian transgression (13 ka BP). A storm wave-base is recognized at the shelf margin (200 m) below which deposits are winnowed and reworked by an upper slope northerly-flowing contour current. Samples from a 143 km transect of 15 stations from the south of Shetland to 260 m on the upper continental slope have been analysed. Bivalve molluscs, barnacles and attached serpulids are the major carbonate contributors with bryozoans, gastropods and echinoderms of secondary importance. The free-living serpulid Ditrupa arietina and erect branching bryozoans are important sediment contributors on the outer shelf. The deep-water coral, Lophelia pertusa, has been recorded from depths of 200–500 m.
The WSS is a distally steepened carbonate ramp shelving at an angle of <1° to the open ocean with continual sweeping of long-period waves, frequent storms and deep-water contour currents.
