HOLOCENE SEA-LEVEL CHANGES AND CRUSTAL MOVEMENTS IN MORECAMBE-BAY, NORTHWEST ENGLAND

Holocene stratigraphy from Skelwith Pool, on the northern side of More cambe Bay, is described. Diatom and pollen analyses and radiocarbon da ting have been undertaken for three sampling sites, from which eight s ea-level index points have been obtained. These index points come from a small homogeneous area and similar palaeoenvironments. Some publish ed sea-level index points from Morecambe Bay have been re-evaluated an d validated by means of diatom analysis. An enhanced sea-level databas e with 28 index points has been used for the reconstruction of Holocen e sea-level history. Relative sea-level rose rapidly around 6870-6510 sc at a maximum rate of +36.7 mm yr(-1). Subsequently, the rate of sea -level change has varied between -8 mm yr(-1) and +12 mm yr(-1). The r ate of relative sea-level changes for the last 3500 years is not clear . Uplift driven by deglaciation is believed to have been interrupted i n the early Holocene by a rapid rise in relative sea-level. Uplift res tarted at 6510 BC but soon declined as glacio-isostatic recovery ended around 3800 BC in the Morecambe Bay area. Since then, crustal movemen ts in the Morecambe Bay area have been minimal. Factors affecting the attitudes of the index points such as sediment compaction of the basal peat and variations in palaeotidal range during the Holocene have bee n considered.