Sea-level change and inner shelf stratigraphy off Northern Ireland

New seismic stratigraphic, vibracore and AMS 14C dates from two sites off the Northern Ireland coast yield information on the deglacial to present sea-level history and shelf evolution of the region. A lowstand of sea level at about 30 m below present sea level recorded by fossils in a lowstand shoreline deposit occurred around 13.4 cal ka B.P. following a period of rapid isostatic uplift associated with a RSL fall of 6–7 cm/yr.Following the lowstand, contrasting styles of sedimentation characterized the two study sites. In the sheltered environment of Belfast Lough, the lowstand shoreline was overtopped and buried by transgressive facies of intertidal and shallow sub-tidal mud and sandy mud. On the high-energy Portrush coast, the inner shelf sedimentary sequence is characterized by a basal conglomerate overlain by well-sorted sands with occasional interbedded gravel.