Late Quaternary sea-level changes, crustal movements and coastal evolution in Northumberland, UK

Northumberland lies in the transition between Holocene emergence and submergence and is thus a critical zone for testing models of isostatic rebound. We have collected data from this area to reconstruct relative sea-level changes and lateral coastline movements for the last 14000 y. These are deposits from tidal marsh, back-barrier wetland and terrestrial environments producing 47 sea-level index points from 12 sites. There is no unequivocal evidence for Late Devensian sea levels above present and the reliable sea-level index points are restricted between -6 m and +2.5 m relative to present and 9.0-2.5 kyr cal. BP. Analysis of these quantifies differential responses to glacio- and hydroisostatic rebound, with the northern sites recording a mid-Holocene sea-level maximum ca. 2.5 m above present, whereas the southern sites show a maximum ca. 0.5 m above present. These observations show a reasonable fit with the predictions from quantitative models of glacio and hydroisostatic rebound, but there is currently no unique solution of Earth and ice model parameters that will explain all the sea-level observations. Copyright (C) 2000 John Wiley and Sons, Ltd.